Original Research—Laryngology and Neurolaryngology
The Changing Landscape of Total Laryngectomy Surgery Sunil P. Verma, MD1, and Hossein Mahboubi, MD, MPH1
Sponsorships or competing interests that may be relevant to content are disclosed at the end of this article.
Abstract Objective. To determine if the number of total laryngectomies (TL) performed in California has changed over a 15-year period from 1996 to 2010. We also sought to investigate if the location of surgery, length of stay, use of rotational/free flaps, cost, and complications changed over this period. Study Design. Cross-sectional. Setting. California Hospital Inpatient Discharge Data sets. Subjects and Methods. All patient records enlisting International Classification of Diseases, Ninth Revision, Clinical Modification procedural codes for total/radical laryngectomy were extracted from 1996 to 2010 data sets. Patients’ demographics were evaluated. Hospitals were coded as university medical centers (UMCs) vs others. Population-adjusted surgery rates, percentage of surgeries with rotational/free flap and/or percutaneous endoscopic gastrostomy (PEG), length of stay, total charges, and disposition status were then analyzed and compared between UMCs and non-UMCs. Results. A total of 4145 TLs were performed in California during 1996 to 2010. The overall number of surgeries declined from 1.3 to 0.6 per 100,000 California residents (P \ .001). The number of surgeries performed in non-UMCs dropped by 70% during this period (P \ .001). The median length of stay increased from 10 to 12 days, and the median total charges increased from $45,000 to $192,000 over the 15-year period. The use of rotational/free flaps more than doubled, and the use of PEG tubes increased 7-fold. Conclusion. The total number of TLs in California has declined and surgeries are currently being performed equally at UMCs and non-UMCs. The use of rotational/free flaps, costs, hospital stay length, and complications have increased over the past 15 years. Keywords laryngectomy, percutaneous endoscopic gastrostomy, free flap, rotational flap Received September 10, 2013; revised October 18, 2013; accepted November 7, 2013.
Otolaryngology– Head and Neck Surgery 2014, Vol. 150(3) 413–418 Ó American Academy of Otolaryngology—Head and Neck Surgery Foundation 2013 Reprints and permission: sagepub.com/journalsPermissions.nav DOI: 10.1177/0194599813514515 http://otojournal.org
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or many years, total laryngectomy (TL) was the primary method of treating advanced laryngeal cancer.1,2 However, due to a number of factors, management of this disease has changed over the past 2 decades.3,4 A major factor was the landmark study in 1991 by the Veterans Affairs Laryngeal Cancer study group in which chemotherapy and radiation was shown to be effective in management of select advanced laryngeal cancer.5 After this trial, the role of TL changed from the standard of care for treatment of advanced laryngeal cancer to being performed primarily for radiation therapy/chemoradiation failures and for extremely advanced cancers. As a result of this, the number of primary TLs performed has decreased. 6-8 With this paradigm shift, there have been new challenges facing the head and neck cancer surgeon. Patients with larger tumors often are left with large pharyngeal defects. Furthermore, patients after chemotherapy and radiation who require TL often are at high risk of fistula and/or stricture formation.9-11 A solution commonly employed to manage these obstacles has been rotational and free flaps.12-14 In addition, gastrostomy tubes have been used to manage patients after surgery.15,16 Despite this, there is a paucity of literature evaluating the trends in use of flaps and gastrostomy tubes in patients undergoing TLs. As the paradigm for management of advanced laryngeal cancer has changed,7,17 the question arises whether the number of individuals receiving TL has changed. Furthermore, since surgery is oftentimes reserved for patients with advanced disease, the question also arises as to where and how these surgeries are being performed. While studies have been performed in the past to look at some but not all of these questions, most research has been performed using nationwide samples that provide extrapolated numbers.6,7,17 This study uses a population database that includes all inpatient surgeries
1
University Voice and Swallowing Center, Department of Otolaryngology– Head and Neck Surgery, University of California Irvine School of Medicine, Irvine, California, USA This article was presented at the 2013 AAO-HNSF Annual Meeting & OTO EXPO; September 29 to October 3, 2013; Vancouver, British Columbia, Canada. Corresponding Author: Sunil P. Verma, MD, University Voice and Swallowing Center, Department of Otolaryngology–Head and Neck Surgery, University of California Irvine School of Medicine, 62 Corporate Park, #115, Irvine, CA 92606, USA. Email: [email protected]
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performed in California to evaluate changes over a 15-year period and investigate the number of TLs being performed, the use of free flaps and the placement of gastrostomy tubes, and changes in costs and complications during the same hospital stay.
Methods Data Source The California Hospital Inpatient Discharge Data sets are released annually by the California Office of Statewide Health Planning and Development (OSHPD). Data are collected from all inpatients discharged from all licensed hospitals in California and provided in the form of deidentified records that contain patient-level data such as demographics, payment source, length of stay, total charges, and International Classification of Diseases, Ninth Revision, Clinical Modification (ICD-9-CM) diagnosis and procedure codes. Further information on data collection, instruments, and methodology is available on the website of the OSHPD.18 The data sets did not contain identifiable patient information; thus, approval for this study by our institutional review board was not required. Data use agreement was signed prior to obtaining the data. The California Hospital Inpatient Discharge Data sets from 1996 to 2010 were obtained and merged. All patient records enlisting ICD-9-CM procedural codes 30.3 complete laryngectomy and 30.4 radical laryngectomy) were extracted. The list of licensed hospitals was obtained from the OSHPD and cross-referenced with the hospital identification numbers in the data sets. Data for total population of California in each year of the study were retrieved from the Census Bureau.19 The incidence of laryngeal cancer in California was obtained from the National Program of Cancer Registries’ (NPCR’s) website.20 These data were available only for 1999 to 2009.
Variables and Definitions For each record, the age, sex, ethnicity, length of stay, total charges, principal payer, and disposition were analyzed. Institution type was classified as university medical center (UMC) vs non-UMC (included all other institutions) according to the Association of American Medical Colleges. Trends in total number of surgeries, population-adjusted surgery rates (number of surgeries per 100,000 California residents), percentage of surgeries with rotational/free flap, and percentage of surgeries with percutaneous endoscopic gastrostomy (PEG) were analyzed and compared between UMCs and non-UMCs. Patient age was categorized into 4 groups: 1 to 17 years, 18 to 34 years, 35 to 64 years, and 65 years and older. Race was recoded as white vs nonwhite (representing African Americans, Native Americans/Eskimo/Aleut, Asian/Pacific Islanders, and others). A patient record was labeled as having received rotational/free flap if any of the following ICD-9-CM procedural codes were listed: 85.71 latissimus dorsi myocutaneous flap, 86.70 pedicle grafts or flaps, 86.70 pedicle or flap graft, not otherwise specified, and 86.74
Table 1. List of International Classification of Diseases, Ninth Revision, Clinical Modification (ICD-9-CM) codes used to define complications. Complications Venous thrombosis Transfusion of packed erythrocytes Hematoma/seroma Seizure Wound infection/ fistula/abscess Pulmonary embolism Pneumonia Acute myocardial infarction Sepsis Postoperative shock
ICD-9-CM codes 453.4-453.42, 453.8, 453.9 99.04 998.1-998.13 436, 780.3-780.39 478.2-478.29, 478.79, 682.1, 686.9, 998.5-998.6 415.1-415.19 480-486 410-410.92 038-038.9, 995.9-995.94, 999.3-999.39 998.0
attachment of pedicle or flap graft to other sites. A patient record was labeled as having received PEG if the following ICD-9-CM procedural code was enlisted: 43.11 percutaneous (endoscopic) gastrostomy (PEG). Length of stay was defined as the total number of days from admission to discharge. Total charges were defined as all charges for services rendered during hospitalization except for hospital-based physician fees. Principal payer was defined as the type of entity or organization expected to pay the greatest share of the patient’s bill. The principal payer was recoded as (1) Medicare, (2) Medi-Cal (Medicaid in California), (3) private insurance coverage (ie, health maintenance organizations), and (4) other (this included self-pay, workers compensation, county indigent programs, other government and indigent programs, research or courtesy patients where no payment was required, or unreported). Perioperative complications were identified using ICD-9CM diagnosis and procedure codes (Table 1). The patient’s disposition status was recoded as (1) routine discharge (patient’s home or residence), (2) death, and (3) other-thanroutine. Other-than-routine included any of the following: acute care within admitting hospital, other care within admitting hospital, long-term care within admitting hospital, acute care at another hospital, other care (not including long-term care) at another hospital, long-term care at another facility, residential care facility, prison/jail, left against medical advice, and home health service.
Statistical Analyses Data distribution of continuous variables was examined for normality. Mean (SD) was calculated for age that had a normal distribution. Median was calculated for total charges and length of stay data, which both had significantly positively skewed distributions requiring analysis using the nonparametric tests. Linear regression analysis was used to
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Figure 1. Number of total laryngectomies (TLs) performed in California, sorted by location, 1996 to 2010. UMC, university medical center.
evaluate the changes over time. The x2 test was used for comparisons between the institution types. Fisher exact test was used where x2 assumptions were not met. The MannWhitney U test was used to compare total charges and length of stay between the institution types, as well as those who underwent rotational/free flaps compared with their counterparts. The SPSS 18.0 (SPSS, Inc, an IBM Company, Chicago, Illinois) was used for all data analyses. A P value of less than .05 was considered significant.
Results A total of 4145 TLs were performed in 254 hospitals in California from 1996 to 2010. Seven hospitals performed more than 100 surgeries annually, 81 hospitals performed 10 to 99 surgeries annually, and the remainder performed less than 10 surgeries annually. During the 15-year period, surgery was performed at a UMC 28.4% of the time. Annually, the percentage of surgeries performed in UMCs increased during the study period from 19.2% in 1996 to 47.5% in 2010 (adjusted R2 = 0.89; P \ .001). The number of TLs performed annually decreased by 43.2% over the study period, from 416 in 1996 to 236 in 2010 (adjusted R2 = 0.82; P \ .001), as shown in Figure 1. There was a 63.1% decrease in TLs performed in non-UMCs, from 336 in 1996 to 124 in 2010 (adjusted R2 = 0.91; P \ .001), despite a statistically insignificant increase in the number of TLs performed annually in UMCs, from 80 in 1996 to 112 in 2010 (adjusted R2 = 0.03; P = .44). According to the NPCR database,20 the incidence of laryngeal cancer in California decreased by 32% over the past decade, from 3.4 per 100,000 California residents in 1999 to 2.3 per 100,000 California residents in 2009 (adjusted R2 = 0.91; P \ .001). The population-adjusted TL rate also declined by 52%, from 1.28 to 0.62 surgeries per 100,000 California residents during 1996 to 2010 (adjusted R2 = 0.83; P \ .001), as shown in Figure 2. The 52% decline in the number of TLs was greater than the 32% decline of laryngeal cancer incidence. The populationadjusted ratio of TL surgery rate to incidence rate decreased from 27.7% to 21.5% during 1999 to 2009 (adjusted R2 = 0.73; P \ .001).
Figure 2. Incidence of laryngeal cancer and population-adjusted surgery rates for total laryngectomies (TLs) performed in California, 1996 to 2010. UMC, university medical center.
The population-adjusted rate of TLs performed in nonUMCs showed a 70% decrease, from 1.03 to 0.33 TLs per 100,000 California residents during this period. The population-adjusted TL rate in UMCs, as shown in Figure 2, slightly increased from 0.25 to 0.30 surgeries per 100,000 California residents, but this change was not statistically significant (adjusted R2 = 0.07; P = .74). The mean (SD) age of patients undergoing TL was 64.3 (11.2) years (median, 65 years; range, 2-85 years); 0.1% were younger than 17 years, 0.8% were 18 to 34 years, 51.5% were 35 to 64 years, and 47.6% were 65 years and older. Of the patients, 79.4% were male and 20.6% were female. There were no changes in patients’ age (P = .31) or sex (P = .11) distribution over time. The patients’ race changed over time (adjusted R2 = 0.39; P = .008), with the percentage of nonwhites increasing from 18.5% to 31.0% from 1996 to 2010. The use of rotational/free flaps with TLs more than doubled during the study period (Figure 3), increasing from 8.2% of TLs in 1996 to 17.8% of TLs in 2010 (adjusted R2 = 0.51; P = .002). This trend was noted in nonUMCs (increase from 5.7% to 12.9% of TLs) (adjusted R2 = 0.65; P \ .001) but remained relatively unchanged in UMCs (19.3%; P = .34). University medical centers were more likely to perform rotational/free flaps compared with non-UMCs during 1996 to 2010 (19.3% vs 6.9%; P \ .001). The use of PEGs increased almost 7-fold, from 3.6% in 1996 to 21.6% in 2010 (adjusted R2 = 0.85; P \ .001). Both UMCs and non-UMCs closely mirrored this pattern,
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Figure 3. Use of rotational/free flaps with total laryngectomies (TLs) performed in California, 1996 to 2010. UMC, university medical center.
although UMCs performed PEG more frequently than nonUMCs (12.4% vs 9.6%; P = .004). The median length of hospital stay increased from 10 days (mean [SD], 13.8 [11.7]; range, 2-101) to 12 days (mean [SD], 14.5 [13.0]; range, 1-160) over the study period. However, this increase was not statistically significant (P = .15). The median length of stay in the university setting, 11 days (mean [SD], 15.9 [13.5]; range, 2-124), was significantly longer than the nonuniversity setting, 10 days (mean [SD], 14.0 [12.7]; range, 1-160; P \ .001). Overall, there was a rise in the median total charges per inpatient stay from $42,239 in 1996 (mean [SD], $68,659 [$111,329]; range, 0-$1,524,874) to $191,561 in 2010 (mean [SD], $236,253 [$225,842]; range, 0-$1,482,112) (adjusted R2 = 0.93; P \ .001). In non-UMCs, the median total charges increased from $39,485 (mean [SD] $47,103 [$42,993]; range, 0-$324,088) to $118,409 (mean [SD] $144,537 [$180,263]; range, 0-$1,430,549) during 1996 to 2010 (adjusted R2 = 0.97; P \ .001). In UMCs, the total charges increased from $83,137 (mean [SD], $159,192 [$216,782]; range, $10,807-$1,524,874) to $276,480 (mean [SD], $337,796 [$228,417]; range, $72,869-$1,482,112) during 1996 to 2010 (adjusted R2 = 0.90; P \ .001). The charges associated with UMCs were significantly higher than non-UMC charges (P \ .001). The length of stay was also significantly associated with higher total charges (adjusted R2 = 0.44; P \ .001). The median length of stay for patients who underwent rotational/free flaps was 15 days (mean [SD], 21.9 [18.8]) compared with 10 days (mean [SD], 13.7 [11.8]) for those who did not (P \ .001). The median total charges were also significantly greater for patients undergoing rotational/free flaps, $161,922 vs $66,986 (mean [SD], $235,523 [$249,526] vs $110,600 [$158,580], respectively; P \ .001). The profile of the principal payer for TLs changed over time. The percentage of patients with Medicare increased
from 40.6% to 48.3% (adjusted R2 = 0.59; P \ .001) and the percentage of patients with Medicaid increased from 15.6% to 22.5% (adjusted R2 = 0.26; P = .03), while the number of patients with private insurance dropped from 36.5% to 26.3% (adjusted R2 = 0.76; P \ .001) during 1996 to 2010. During the study period, 1312 (31.7%) of patients experienced at least 1 complication during admission. There was an increase in the overall rate of complications from 28.1% in 1996 to 35.2% in 2010 (adjusted R2 = 0.31; P = .01). The most common complications over the 15-year period were fistula/abscess/wound infection in 13.5%, packed red blood cell transfusion in 11.6%, pneumonia in 6.5%, hematoma/seroma in 4.5%, sepsis in 2.0%, venous thrombosis in 1.5%, seizure in 1.4%, acute myocardial infarction in 1.1%, pulmonary embolism in 0.8%, and postoperative shock in 0.1%. Over time, fewer patients were discharged home with no continued care. This percentage decreased from 41.1% to 28.8% during 1996 to 2010 (adjusted R2 = 0.59; P \ .001). During the same period, the percentage of patients having other-than-routine disposition status, including receiving further care, increased from 56.7% to 69.9% (adjusted R2 = 0.65; P \ .001), while the mortality rate remained relatively unchanged, with an average of 1.6% (P \ .001).
Discussion The management of laryngeal cancer has changed dramatically over the past 20 years. After the Veterans Affairs Laryngeal Cancer Study Group demonstrated that chemoradiation was a viable alternative for the management of select advanced laryngeal cancers, the era of ‘‘organ preservation’’ was born. At the same time, the nationwide incidence of smoking and the number of patients with laryngeal cancer decreased.3,17,21 As a result, the number of patients undergoing TL decreased 48% nationwide.7 This study was undertaken to examine how these changes influenced TL surgery in California. A number of interesting findings were observed. First, it is possible that the number of TLs was previously underestimated. In California alone, there have been, on average, 276 TLs performed per year, much larger than the previously estimated 109 TLs performed annually in the entire western US region of 13 states.17 Nonetheless, the number of TLs has precipitously dropped over the past 15 years in California, especially when adjusted for population increase. This drop has been mostly due to the noted decline in non-UMCs despite a relatively stable surgery rate in UMCs over time. Not surprisingly, the number of patients requiring rotational and free flaps has increased since 1996. This is likely due to a number of factors. Patients who require TL likely have larger volume disease in the primary setting or have failed chemoradiation. In both scenarios, a large laryngopharyngeal defect may result after surgery requiring reconstruction with local or regional flaps. As the number of patients who have had larger surgeries and longer inpatient stays have increased, the number of PEG tubes placed has arisen as well.4 Free/rotational flaps have also been found to result in fewer fistula and stricture formation when used in
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salvage laryngectomy.14,22 This could be another possible explanation for the observed increase in using of flaps. At the start of this study period, more than 80% of TLs in California were performed at non-UMCs. Interestingly, there has been a large shift in this landscape, as in 2010, TLs were evenly performed in UMCs and non-UMCs. Other studies have also demonstrated similar nationwide trends.7,13,17 This migration toward UMCs may be due several factors, including easier coordination for care and access to further resources in case of complication. Through this study, the number of rotational and free flaps was consistently performed more often at UMCs. This was seen similarly by others13 and may explain part of the shift toward UMCs. Nonetheless, non-UMCs continue to play a critical role in TL surgery. According to the US Bureau of Labor, the average hospitalbased inflation between 1996 and 2010 was 126.95%.23 In the current study, the median total charges increased by 353% for all TLs, by 200% for TLs in non-UMCs, by 233% for TLs in UMCs, and by 142% for TLs with rotational/free flaps. These increased rates are more than what would be expected solely based on the inflation rate and may be explained by the observed increasing trends in length of stay, use of flaps, and PEG tubes placement. The mortality rate after TL of approximately 1.6% did not change over time and was similar to the previously reported rates of 1.1% to 1.4%.7 In addition, this study revealed that over time, complication rates increased while fewer patients were discharged to their home residence with no continued care. These findings together may once again reflect the increased complexity of TLs likely due to the changes in treatment protocols and increased number of salvage TLs. A number of limitations existed in this study mainly due to the nature of the data sets. Based on the recorded data, it was not possible to distinguish between primary and salvage TLs. Furthermore, data on tumor size, anatomical location, staging, and survival were not reported. Finally, data were recorded in form of ICD-9-CM codes and could be subject to potential miscoding and data entry bias. Nonetheless, California Hospital Inpatient Discharge Data sets offered a unique opportunity to look at all TLs performed over a 15year period. The considerable population of California with its diverse demographics and socioeconomic structure would provide a representing sample of the United States. Future studies are required to further investigate the observed trends of this study. Author Contributions Sunil P. Verma, designing and interpretation of data, drafting the article and final approval of the version to be published; Hossein Mahboubi, designing, analysis and interpretation of data, drafting the article and final approval of the version to be published.
Disclosures Competing interests: Sunil P. Verma was a consultant for Acclarent (July 2013).
Sponsorships: None. Funding source: None.
References 1. Babin E, Blanchard D, Hitier M. Management of total laryngectomy patients over time: from the consultation announcing the diagnosis to long term follow-up. Eur Arch Otorhinolaryngol. 2011;268:1407-1419. 2. Chen AY, Schrag N, Hao Y, et al. Changes in treatment of advanced laryngeal cancer 1985-2001. Otolaryngol Head Neck Surg. 2006;135:831-837. 3. Hoffman HT, Porter K, Karnell LH, et al. Laryngeal cancer in the United States: changes in demographics, patterns of care, and survival. Laryngoscope. 2006;116:1-13. 4. Takes RP, Strojan P, Silver CE, et al. Current trends in initial management of hypopharyngeal cancer: the declining use of open surgery. Head Neck. 2012;34:270-281. 5. Department of Veterans Affairs Laryngeal Cancer Study Group. Induction chemotherapy plus radiation compared with surgery plus radiation in patients with advanced laryngeal cancer. N Engl J Med. 1991;324:1685-1690. 6. Chen AY, Fedewa S, Zhu J. Temporal trends in the treatment of early- and advanced-stage laryngeal cancer in the United States, 1985-2007. Arch Otolaryngol Head Neck Surg. 2011; 137:1017-1024. 7. Maddox PT, Davies L. Trends in total laryngectomy in the era of organ preservation: a population-based study. Otolaryngol Head Neck Surg. 2012;147:85-90. 8. Patel UA, Moore BA, Wax M, et al. Impact of pharyngeal closure technique on fistula after salvage laryngectomy [published online April 10, 2013]. JAMA Otolaryngol Head Neck Surg. doi:10.1001/jamaoto.2013.2761. 9. Ganly I, Patel S, Matsuo J, et al. Postoperative complications of salvage total laryngectomy. Cancer. 2005;103:2073-2081. 10. Sassler AM, Esclamado RM, Wolf GT. Surgery after organ preservation therapy: analysis of wound complications. Arch Otolaryngol Head Neck Surg. 1995;121:162-165. 11. Paydarfar JA, Birkmeyer NJ. Complications in head and neck surgery: a meta-analysis of postlaryngectomy pharyngocutaneous fistula. Arch Otolaryngol Head Neck Surg. 2006;132:67-72. 12. McCaffrey TV. Surgical treatment in head and neck cancer. Curr Opin Oncol. 1991;3:519-522. 13. Gourin CG, Frick KD. National trends in laryngeal cancer surgery and the effect of surgeon and hospital volume on shortterm outcomes and cost of care. Laryngoscope. 2012;122:88-94. 14. Withrow KP, Rosenthal EL, Gourin CG, et al. Free tissue transfer to manage salvage laryngectomy defects after organ preservation failure. Laryngoscope. 2007;117:781-784. 15. Lujber L, Fabian G, Pytel J. Inserting a percutaneous endoscopic gastrostomy tube via a cervical fistula formed after major surgery on a patient with a head and neck tumor. Surg Laparosc Endosc Percutan Tech. 2001;11:327-329. 16. Mekhail TM, Adelstein DJ, Rybicki LA, Larto MA, Saxton JP, Lavertu P. Enteral nutrition during the treatment of head and neck carcinoma: is a percutaneous endoscopic gastrostomy tube preferable to a nasogastric tube? Cancer. 2001;91:1785-1790.
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17. Orosco RK, Weisman RA, Chang DC, Brumund KT. Total laryngectomy: national and regional case volume trends 19982008. Otolaryngol Head Neck Surg. 2013;148:243-248. 18. Patient Discharge Data File Documentation. http://www. oshpd.ca.gov/HID/Products/PatDischargeData/PublicDataSet/ index.html. Accessed August 20, 2012. 19. United States Census Bureau Intercensal Estimates. http:// www.census.gov/popest/data/intercensal/index.html. Accessed August 20, 2012. 20. Cancer—United States Cancer Statistics (USCS) data—2009 selected cancers ranked by state. http://apps.nccd.cdc.gov/uscs/ cancersrankedbystate.aspx. Accessed August 20, 2012.
21. Cosetti M, Yu GP, Schantz SP. Five-year survival rates and time trends of laryngeal cancer in the US population. Arch Otolaryngol Head Neck Surg. 2008;134:370-379. 22. Hanasono MM, Lin D, Wax MK, Rosenthal EL. Closure of laryngectomy defects in the age of chemoradiation therapy. Head Neck. 2012;34:580-588. 23. Metric Mash. US inflation rate for hospital and related services. http:// metricmash.com/inflation.aspx?code=SEMD. Accessed October 15, 2013.
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The Changing Landscape of Total Laryngectomy Surgery Sunil P. Verma, MD1, and Hossein Mahboubi, MD, MPH1
Sponsorships or competing interests that may be relevant to content are disclosed at the end of this article.
Abstract Objective. To determine if the number of total laryngectomies (TL) performed in California has changed over a 15-year period from 1996 to 2010. We also sought to investigate if the location of surgery, length of stay, use of rotational/free flaps, cost, and complications changed over this period. Study Design. Cross-sectional. Setting. California Hospital Inpatient Discharge Data sets. Subjects and Methods. All patient records enlisting International Classification of Diseases, Ninth Revision, Clinical Modification procedural codes for total/radical laryngectomy were extracted from 1996 to 2010 data sets. Patients’ demographics were evaluated. Hospitals were coded as university medical centers (UMCs) vs others. Population-adjusted surgery rates, percentage of surgeries with rotational/free flap and/or percutaneous endoscopic gastrostomy (PEG), length of stay, total charges, and disposition status were then analyzed and compared between UMCs and non-UMCs. Results. A total of 4145 TLs were performed in California during 1996 to 2010. The overall number of surgeries declined from 1.3 to 0.6 per 100,000 California residents (P \ .001). The number of surgeries performed in non-UMCs dropped by 70% during this period (P \ .001). The median length of stay increased from 10 to 12 days, and the median total charges increased from $45,000 to $192,000 over the 15-year period. The use of rotational/free flaps more than doubled, and the use of PEG tubes increased 7-fold. Conclusion. The total number of TLs in California has declined and surgeries are currently being performed equally at UMCs and non-UMCs. The use of rotational/free flaps, costs, hospital stay length, and complications have increased over the past 15 years. Keywords laryngectomy, percutaneous endoscopic gastrostomy, free flap, rotational flap Received September 10, 2013; revised October 18, 2013; accepted November 7, 2013.
Otolaryngology– Head and Neck Surgery 2014, Vol. 150(3) 413–418 Ó American Academy of Otolaryngology—Head and Neck Surgery Foundation 2013 Reprints and permission: sagepub.com/journalsPermissions.nav DOI: 10.1177/0194599813514515 http://otojournal.org
F
or many years, total laryngectomy (TL) was the primary method of treating advanced laryngeal cancer.1,2 However, due to a number of factors, management of this disease has changed over the past 2 decades.3,4 A major factor was the landmark study in 1991 by the Veterans Affairs Laryngeal Cancer study group in which chemotherapy and radiation was shown to be effective in management of select advanced laryngeal cancer.5 After this trial, the role of TL changed from the standard of care for treatment of advanced laryngeal cancer to being performed primarily for radiation therapy/chemoradiation failures and for extremely advanced cancers. As a result of this, the number of primary TLs performed has decreased. 6-8 With this paradigm shift, there have been new challenges facing the head and neck cancer surgeon. Patients with larger tumors often are left with large pharyngeal defects. Furthermore, patients after chemotherapy and radiation who require TL often are at high risk of fistula and/or stricture formation.9-11 A solution commonly employed to manage these obstacles has been rotational and free flaps.12-14 In addition, gastrostomy tubes have been used to manage patients after surgery.15,16 Despite this, there is a paucity of literature evaluating the trends in use of flaps and gastrostomy tubes in patients undergoing TLs. As the paradigm for management of advanced laryngeal cancer has changed,7,17 the question arises whether the number of individuals receiving TL has changed. Furthermore, since surgery is oftentimes reserved for patients with advanced disease, the question also arises as to where and how these surgeries are being performed. While studies have been performed in the past to look at some but not all of these questions, most research has been performed using nationwide samples that provide extrapolated numbers.6,7,17 This study uses a population database that includes all inpatient surgeries
1
University Voice and Swallowing Center, Department of Otolaryngology– Head and Neck Surgery, University of California Irvine School of Medicine, Irvine, California, USA This article was presented at the 2013 AAO-HNSF Annual Meeting & OTO EXPO; September 29 to October 3, 2013; Vancouver, British Columbia, Canada. Corresponding Author: Sunil P. Verma, MD, University Voice and Swallowing Center, Department of Otolaryngology–Head and Neck Surgery, University of California Irvine School of Medicine, 62 Corporate Park, #115, Irvine, CA 92606, USA. Email: [email protected]
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performed in California to evaluate changes over a 15-year period and investigate the number of TLs being performed, the use of free flaps and the placement of gastrostomy tubes, and changes in costs and complications during the same hospital stay.
Methods Data Source The California Hospital Inpatient Discharge Data sets are released annually by the California Office of Statewide Health Planning and Development (OSHPD). Data are collected from all inpatients discharged from all licensed hospitals in California and provided in the form of deidentified records that contain patient-level data such as demographics, payment source, length of stay, total charges, and International Classification of Diseases, Ninth Revision, Clinical Modification (ICD-9-CM) diagnosis and procedure codes. Further information on data collection, instruments, and methodology is available on the website of the OSHPD.18 The data sets did not contain identifiable patient information; thus, approval for this study by our institutional review board was not required. Data use agreement was signed prior to obtaining the data. The California Hospital Inpatient Discharge Data sets from 1996 to 2010 were obtained and merged. All patient records enlisting ICD-9-CM procedural codes 30.3 complete laryngectomy and 30.4 radical laryngectomy) were extracted. The list of licensed hospitals was obtained from the OSHPD and cross-referenced with the hospital identification numbers in the data sets. Data for total population of California in each year of the study were retrieved from the Census Bureau.19 The incidence of laryngeal cancer in California was obtained from the National Program of Cancer Registries’ (NPCR’s) website.20 These data were available only for 1999 to 2009.
Variables and Definitions For each record, the age, sex, ethnicity, length of stay, total charges, principal payer, and disposition were analyzed. Institution type was classified as university medical center (UMC) vs non-UMC (included all other institutions) according to the Association of American Medical Colleges. Trends in total number of surgeries, population-adjusted surgery rates (number of surgeries per 100,000 California residents), percentage of surgeries with rotational/free flap, and percentage of surgeries with percutaneous endoscopic gastrostomy (PEG) were analyzed and compared between UMCs and non-UMCs. Patient age was categorized into 4 groups: 1 to 17 years, 18 to 34 years, 35 to 64 years, and 65 years and older. Race was recoded as white vs nonwhite (representing African Americans, Native Americans/Eskimo/Aleut, Asian/Pacific Islanders, and others). A patient record was labeled as having received rotational/free flap if any of the following ICD-9-CM procedural codes were listed: 85.71 latissimus dorsi myocutaneous flap, 86.70 pedicle grafts or flaps, 86.70 pedicle or flap graft, not otherwise specified, and 86.74
Table 1. List of International Classification of Diseases, Ninth Revision, Clinical Modification (ICD-9-CM) codes used to define complications. Complications Venous thrombosis Transfusion of packed erythrocytes Hematoma/seroma Seizure Wound infection/ fistula/abscess Pulmonary embolism Pneumonia Acute myocardial infarction Sepsis Postoperative shock
ICD-9-CM codes 453.4-453.42, 453.8, 453.9 99.04 998.1-998.13 436, 780.3-780.39 478.2-478.29, 478.79, 682.1, 686.9, 998.5-998.6 415.1-415.19 480-486 410-410.92 038-038.9, 995.9-995.94, 999.3-999.39 998.0
attachment of pedicle or flap graft to other sites. A patient record was labeled as having received PEG if the following ICD-9-CM procedural code was enlisted: 43.11 percutaneous (endoscopic) gastrostomy (PEG). Length of stay was defined as the total number of days from admission to discharge. Total charges were defined as all charges for services rendered during hospitalization except for hospital-based physician fees. Principal payer was defined as the type of entity or organization expected to pay the greatest share of the patient’s bill. The principal payer was recoded as (1) Medicare, (2) Medi-Cal (Medicaid in California), (3) private insurance coverage (ie, health maintenance organizations), and (4) other (this included self-pay, workers compensation, county indigent programs, other government and indigent programs, research or courtesy patients where no payment was required, or unreported). Perioperative complications were identified using ICD-9CM diagnosis and procedure codes (Table 1). The patient’s disposition status was recoded as (1) routine discharge (patient’s home or residence), (2) death, and (3) other-thanroutine. Other-than-routine included any of the following: acute care within admitting hospital, other care within admitting hospital, long-term care within admitting hospital, acute care at another hospital, other care (not including long-term care) at another hospital, long-term care at another facility, residential care facility, prison/jail, left against medical advice, and home health service.
Statistical Analyses Data distribution of continuous variables was examined for normality. Mean (SD) was calculated for age that had a normal distribution. Median was calculated for total charges and length of stay data, which both had significantly positively skewed distributions requiring analysis using the nonparametric tests. Linear regression analysis was used to
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Figure 1. Number of total laryngectomies (TLs) performed in California, sorted by location, 1996 to 2010. UMC, university medical center.
evaluate the changes over time. The x2 test was used for comparisons between the institution types. Fisher exact test was used where x2 assumptions were not met. The MannWhitney U test was used to compare total charges and length of stay between the institution types, as well as those who underwent rotational/free flaps compared with their counterparts. The SPSS 18.0 (SPSS, Inc, an IBM Company, Chicago, Illinois) was used for all data analyses. A P value of less than .05 was considered significant.
Results A total of 4145 TLs were performed in 254 hospitals in California from 1996 to 2010. Seven hospitals performed more than 100 surgeries annually, 81 hospitals performed 10 to 99 surgeries annually, and the remainder performed less than 10 surgeries annually. During the 15-year period, surgery was performed at a UMC 28.4% of the time. Annually, the percentage of surgeries performed in UMCs increased during the study period from 19.2% in 1996 to 47.5% in 2010 (adjusted R2 = 0.89; P \ .001). The number of TLs performed annually decreased by 43.2% over the study period, from 416 in 1996 to 236 in 2010 (adjusted R2 = 0.82; P \ .001), as shown in Figure 1. There was a 63.1% decrease in TLs performed in non-UMCs, from 336 in 1996 to 124 in 2010 (adjusted R2 = 0.91; P \ .001), despite a statistically insignificant increase in the number of TLs performed annually in UMCs, from 80 in 1996 to 112 in 2010 (adjusted R2 = 0.03; P = .44). According to the NPCR database,20 the incidence of laryngeal cancer in California decreased by 32% over the past decade, from 3.4 per 100,000 California residents in 1999 to 2.3 per 100,000 California residents in 2009 (adjusted R2 = 0.91; P \ .001). The population-adjusted TL rate also declined by 52%, from 1.28 to 0.62 surgeries per 100,000 California residents during 1996 to 2010 (adjusted R2 = 0.83; P \ .001), as shown in Figure 2. The 52% decline in the number of TLs was greater than the 32% decline of laryngeal cancer incidence. The populationadjusted ratio of TL surgery rate to incidence rate decreased from 27.7% to 21.5% during 1999 to 2009 (adjusted R2 = 0.73; P \ .001).
Figure 2. Incidence of laryngeal cancer and population-adjusted surgery rates for total laryngectomies (TLs) performed in California, 1996 to 2010. UMC, university medical center.
The population-adjusted rate of TLs performed in nonUMCs showed a 70% decrease, from 1.03 to 0.33 TLs per 100,000 California residents during this period. The population-adjusted TL rate in UMCs, as shown in Figure 2, slightly increased from 0.25 to 0.30 surgeries per 100,000 California residents, but this change was not statistically significant (adjusted R2 = 0.07; P = .74). The mean (SD) age of patients undergoing TL was 64.3 (11.2) years (median, 65 years; range, 2-85 years); 0.1% were younger than 17 years, 0.8% were 18 to 34 years, 51.5% were 35 to 64 years, and 47.6% were 65 years and older. Of the patients, 79.4% were male and 20.6% were female. There were no changes in patients’ age (P = .31) or sex (P = .11) distribution over time. The patients’ race changed over time (adjusted R2 = 0.39; P = .008), with the percentage of nonwhites increasing from 18.5% to 31.0% from 1996 to 2010. The use of rotational/free flaps with TLs more than doubled during the study period (Figure 3), increasing from 8.2% of TLs in 1996 to 17.8% of TLs in 2010 (adjusted R2 = 0.51; P = .002). This trend was noted in nonUMCs (increase from 5.7% to 12.9% of TLs) (adjusted R2 = 0.65; P \ .001) but remained relatively unchanged in UMCs (19.3%; P = .34). University medical centers were more likely to perform rotational/free flaps compared with non-UMCs during 1996 to 2010 (19.3% vs 6.9%; P \ .001). The use of PEGs increased almost 7-fold, from 3.6% in 1996 to 21.6% in 2010 (adjusted R2 = 0.85; P \ .001). Both UMCs and non-UMCs closely mirrored this pattern,
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Figure 3. Use of rotational/free flaps with total laryngectomies (TLs) performed in California, 1996 to 2010. UMC, university medical center.
although UMCs performed PEG more frequently than nonUMCs (12.4% vs 9.6%; P = .004). The median length of hospital stay increased from 10 days (mean [SD], 13.8 [11.7]; range, 2-101) to 12 days (mean [SD], 14.5 [13.0]; range, 1-160) over the study period. However, this increase was not statistically significant (P = .15). The median length of stay in the university setting, 11 days (mean [SD], 15.9 [13.5]; range, 2-124), was significantly longer than the nonuniversity setting, 10 days (mean [SD], 14.0 [12.7]; range, 1-160; P \ .001). Overall, there was a rise in the median total charges per inpatient stay from $42,239 in 1996 (mean [SD], $68,659 [$111,329]; range, 0-$1,524,874) to $191,561 in 2010 (mean [SD], $236,253 [$225,842]; range, 0-$1,482,112) (adjusted R2 = 0.93; P \ .001). In non-UMCs, the median total charges increased from $39,485 (mean [SD] $47,103 [$42,993]; range, 0-$324,088) to $118,409 (mean [SD] $144,537 [$180,263]; range, 0-$1,430,549) during 1996 to 2010 (adjusted R2 = 0.97; P \ .001). In UMCs, the total charges increased from $83,137 (mean [SD], $159,192 [$216,782]; range, $10,807-$1,524,874) to $276,480 (mean [SD], $337,796 [$228,417]; range, $72,869-$1,482,112) during 1996 to 2010 (adjusted R2 = 0.90; P \ .001). The charges associated with UMCs were significantly higher than non-UMC charges (P \ .001). The length of stay was also significantly associated with higher total charges (adjusted R2 = 0.44; P \ .001). The median length of stay for patients who underwent rotational/free flaps was 15 days (mean [SD], 21.9 [18.8]) compared with 10 days (mean [SD], 13.7 [11.8]) for those who did not (P \ .001). The median total charges were also significantly greater for patients undergoing rotational/free flaps, $161,922 vs $66,986 (mean [SD], $235,523 [$249,526] vs $110,600 [$158,580], respectively; P \ .001). The profile of the principal payer for TLs changed over time. The percentage of patients with Medicare increased
from 40.6% to 48.3% (adjusted R2 = 0.59; P \ .001) and the percentage of patients with Medicaid increased from 15.6% to 22.5% (adjusted R2 = 0.26; P = .03), while the number of patients with private insurance dropped from 36.5% to 26.3% (adjusted R2 = 0.76; P \ .001) during 1996 to 2010. During the study period, 1312 (31.7%) of patients experienced at least 1 complication during admission. There was an increase in the overall rate of complications from 28.1% in 1996 to 35.2% in 2010 (adjusted R2 = 0.31; P = .01). The most common complications over the 15-year period were fistula/abscess/wound infection in 13.5%, packed red blood cell transfusion in 11.6%, pneumonia in 6.5%, hematoma/seroma in 4.5%, sepsis in 2.0%, venous thrombosis in 1.5%, seizure in 1.4%, acute myocardial infarction in 1.1%, pulmonary embolism in 0.8%, and postoperative shock in 0.1%. Over time, fewer patients were discharged home with no continued care. This percentage decreased from 41.1% to 28.8% during 1996 to 2010 (adjusted R2 = 0.59; P \ .001). During the same period, the percentage of patients having other-than-routine disposition status, including receiving further care, increased from 56.7% to 69.9% (adjusted R2 = 0.65; P \ .001), while the mortality rate remained relatively unchanged, with an average of 1.6% (P \ .001).
Discussion The management of laryngeal cancer has changed dramatically over the past 20 years. After the Veterans Affairs Laryngeal Cancer Study Group demonstrated that chemoradiation was a viable alternative for the management of select advanced laryngeal cancers, the era of ‘‘organ preservation’’ was born. At the same time, the nationwide incidence of smoking and the number of patients with laryngeal cancer decreased.3,17,21 As a result, the number of patients undergoing TL decreased 48% nationwide.7 This study was undertaken to examine how these changes influenced TL surgery in California. A number of interesting findings were observed. First, it is possible that the number of TLs was previously underestimated. In California alone, there have been, on average, 276 TLs performed per year, much larger than the previously estimated 109 TLs performed annually in the entire western US region of 13 states.17 Nonetheless, the number of TLs has precipitously dropped over the past 15 years in California, especially when adjusted for population increase. This drop has been mostly due to the noted decline in non-UMCs despite a relatively stable surgery rate in UMCs over time. Not surprisingly, the number of patients requiring rotational and free flaps has increased since 1996. This is likely due to a number of factors. Patients who require TL likely have larger volume disease in the primary setting or have failed chemoradiation. In both scenarios, a large laryngopharyngeal defect may result after surgery requiring reconstruction with local or regional flaps. As the number of patients who have had larger surgeries and longer inpatient stays have increased, the number of PEG tubes placed has arisen as well.4 Free/rotational flaps have also been found to result in fewer fistula and stricture formation when used in
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salvage laryngectomy.14,22 This could be another possible explanation for the observed increase in using of flaps. At the start of this study period, more than 80% of TLs in California were performed at non-UMCs. Interestingly, there has been a large shift in this landscape, as in 2010, TLs were evenly performed in UMCs and non-UMCs. Other studies have also demonstrated similar nationwide trends.7,13,17 This migration toward UMCs may be due several factors, including easier coordination for care and access to further resources in case of complication. Through this study, the number of rotational and free flaps was consistently performed more often at UMCs. This was seen similarly by others13 and may explain part of the shift toward UMCs. Nonetheless, non-UMCs continue to play a critical role in TL surgery. According to the US Bureau of Labor, the average hospitalbased inflation between 1996 and 2010 was 126.95%.23 In the current study, the median total charges increased by 353% for all TLs, by 200% for TLs in non-UMCs, by 233% for TLs in UMCs, and by 142% for TLs with rotational/free flaps. These increased rates are more than what would be expected solely based on the inflation rate and may be explained by the observed increasing trends in length of stay, use of flaps, and PEG tubes placement. The mortality rate after TL of approximately 1.6% did not change over time and was similar to the previously reported rates of 1.1% to 1.4%.7 In addition, this study revealed that over time, complication rates increased while fewer patients were discharged to their home residence with no continued care. These findings together may once again reflect the increased complexity of TLs likely due to the changes in treatment protocols and increased number of salvage TLs. A number of limitations existed in this study mainly due to the nature of the data sets. Based on the recorded data, it was not possible to distinguish between primary and salvage TLs. Furthermore, data on tumor size, anatomical location, staging, and survival were not reported. Finally, data were recorded in form of ICD-9-CM codes and could be subject to potential miscoding and data entry bias. Nonetheless, California Hospital Inpatient Discharge Data sets offered a unique opportunity to look at all TLs performed over a 15year period. The considerable population of California with its diverse demographics and socioeconomic structure would provide a representing sample of the United States. Future studies are required to further investigate the observed trends of this study. Author Contributions Sunil P. Verma, designing and interpretation of data, drafting the article and final approval of the version to be published; Hossein Mahboubi, designing, analysis and interpretation of data, drafting the article and final approval of the version to be published.
Disclosures Competing interests: Sunil P. Verma was a consultant for Acclarent (July 2013).
Sponsorships: None. Funding source: None.
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