OBES SURG (2014) 24:2134–2137 DOI 10.1007/s11695-014-1336-5
ORIGINAL CONTRIBUTIONS
The True Incidence of Gastric GIST—a Study Based on Morbidly Obese Patients Undergoing Sleeve Gastrectomy Jonathan B. Yuval & Abed Khalaileh & Mahmoud Abu-Gazala & Yair Shachar & Andrei Keidar & Yoav Mintz & Aviram Nissan & Ram Elazary
Published online: 27 June 2014 # Springer Science+Business Media New York 2014
Abstract Background Gastrointestinal stromal tumor (GIST) is a rare neoplasm of the alimentary tract. Previous reports described an incidence of 1 per 100,000. Laparoscopic sleeve gastrectomy (LSG) provides pathological specimens of the majority of the stomach. We examined the pathology from LSG and the incidence and location of GIST. The aim of this study was to study the incidence of asymptomatic GISTs found during LSG at our institution. Methods A search was conducted in a prospectively maintained bariatric registry. Data collected included the following: gender, age, body mass index (BMI), and concomitant hypertension or diabetes mellitus. Histopathology reports were
Drs. Jonathan B. Yuval and Abed Khalaileh have equally contributed to this study. J. B. Yuval : A. Khalaileh : M. Abu-Gazala : Y. Shachar : A. Keidar : Y. Mintz : A. Nissan : R. Elazary (*) Department of General Surgery, Hadassah-Hebrew University Medical Center, Kyriat Hadassah, P.O. Box 12000, Jerusalem 91120, Israel e-mail: [email protected]
reviewed for incidental GIST. We compared the patients with incidental GIST to the rest of the cohort. Results Pathology reports of 827 patients that underwent LSG between 2007 and 2014 were reviewed. Five patients had GIST in the resected stomach, an incidence of 0.6 %. The group of patients with GIST had lower BMI and older age compared to the remaining 822 patients. All tumors were located close to the lesser curvature. Conclusions The incidence of GIST found in this cohort is significantly higher than previously reported. This may be due to an association between these tumors and obesity or because asymptomatic GISTs are underdiagnosed in the general population. These tumors are particularly common in older patients and special attention must be given when performing LSG on this subpopulation. The stomach should be inspected thoroughly before resection. A tumor on the lesser curvature may necessitate changing the surgical plan or aborting the procedure. Keywords Gastrointestinal stromal tumor (GIST) . Sleeve . Gastrectomy . Bariatric
J. B. Yuval e-mail: [email protected] A. Khalaileh e-mail: [email protected]
Introduction
M. Abu-Gazala e-mail: [email protected]
Gastrointestinal stromal tumor (GIST) is a rare mesenchymal neoplasm of the alimentary tract [1]. This tumor is caused by specific gain of function mutations in the C-Kit (CD117), tyrosine kinase protein, or in platelet-derived growth factor receptor alpha (PDGFRα) [2, 3]. It has been proposed that GIST arises from the interstitial cell of Cajal, considered the pacemaker cells of the alimentary tract [4] . Cajal cells and GIST cells are similar histologically in exhibiting both neuronal and smooth muscle cell features in electron microscopy and immunohistochemistry[5].
Y. Shachar e-mail: [email protected] A. Keidar e-mail: [email protected] Y. Mintz e-mail: [email protected] A. Nissan e-mail: [email protected]
OBES SURG (2014) 24:2134–2137
Previous reports regarding the epidemiology of GIST described an incidence of 0.5 to 2 per 100,000 accounting for only 0.3–0.5 % of all gastrointestinal tumors [6, 7]. Data from autopsies, however, point out a tendency toward a higher incidence of 20 per 100,000 for clinically insignificant GISTs [7]. The majority of GISTs are diagnosed in patients 50 years of age or older [8]. There are reports of equal distribution between sexes or slight male predominance [4, 8]. GISTs can be found anywhere along the alimentary tract but are most commonly found in the stomach (60 %) followed by the small intestine (30 %), large bowel (5 %), and rectum (5 %)[1, 4, 6]. The clinical behavior of GIST following surgical resection is variable [9]. Even completely resected small tumors may recur locoregionally or metastasize. The National Institutes of Health (NIH) have developed a consensus scheme to evaluate the clinical course of GIST based on tumor size and mitotic index [10]. Complete surgical excision is the mainstay of treatment [11] and high risk lesions should be treated with adjuvant imatinib mesylate. Due to the worldwide epidemic of obesity, bariatric surgical procedures are becoming increasingly common [12]. Unlike Roux-en-Y gastric bypass (RYGB) and laparascopic adjustable gastric banding (LAGB), laparoscopic sleeve gastrectomy (LSG) provides pathological specimens of the majority of the stomach, the organ where GISTs are most commonly found. It is therefore interesting to examine the pathological reports of LSG in order to study the incidence and anatomical location of GIST in the obese population. The aim of this study was to describe the incidence of asymptomatic GISTs found during in a cohort of morbidly obese patients undergoing LSG in a single institution.
Materials We conducted a retrospective study using our prospectively collected data of our medical center's metabolic and bariatric registry approved by Institutional Ethical Committee (IEC, Helsinki Committee). We identified patients that underwent LSG in whom a GIST was found in the resected pathological specimen. Data collected included the following: gender, age, body mass index (BMI), and the existence of hypertension or type 2 diabetes mellitus. We also focused on the tumor parameters: location, size, mitotic index, and staining for C-kit, CD34, CD117, and PDGFRα. The group of patients diagnosed with GIST (GIST group) was compared to the rest of the patients (control group). We presented continuous variables as mean±standard deviation (SD), and statistical difference was calculated using the unpaired t test. Categorical variables were compared using the Fisher's exact test. Both types of variables were defined as statistically significant if the p value was less than 0.01 (Table 1).
2135 Table 1 Patients’ characteristics GIST group n=5
Control group n=822
p value
Gender (m/f) Age (years) BMI (kg/m2) T2DM (%)
4/1 55.4+7 36+2.2 60
1/2 39+12.2 42.4+5.2 19.7
ORIGINAL CONTRIBUTIONS
The True Incidence of Gastric GIST—a Study Based on Morbidly Obese Patients Undergoing Sleeve Gastrectomy Jonathan B. Yuval & Abed Khalaileh & Mahmoud Abu-Gazala & Yair Shachar & Andrei Keidar & Yoav Mintz & Aviram Nissan & Ram Elazary
Published online: 27 June 2014 # Springer Science+Business Media New York 2014
Abstract Background Gastrointestinal stromal tumor (GIST) is a rare neoplasm of the alimentary tract. Previous reports described an incidence of 1 per 100,000. Laparoscopic sleeve gastrectomy (LSG) provides pathological specimens of the majority of the stomach. We examined the pathology from LSG and the incidence and location of GIST. The aim of this study was to study the incidence of asymptomatic GISTs found during LSG at our institution. Methods A search was conducted in a prospectively maintained bariatric registry. Data collected included the following: gender, age, body mass index (BMI), and concomitant hypertension or diabetes mellitus. Histopathology reports were
Drs. Jonathan B. Yuval and Abed Khalaileh have equally contributed to this study. J. B. Yuval : A. Khalaileh : M. Abu-Gazala : Y. Shachar : A. Keidar : Y. Mintz : A. Nissan : R. Elazary (*) Department of General Surgery, Hadassah-Hebrew University Medical Center, Kyriat Hadassah, P.O. Box 12000, Jerusalem 91120, Israel e-mail: [email protected]
reviewed for incidental GIST. We compared the patients with incidental GIST to the rest of the cohort. Results Pathology reports of 827 patients that underwent LSG between 2007 and 2014 were reviewed. Five patients had GIST in the resected stomach, an incidence of 0.6 %. The group of patients with GIST had lower BMI and older age compared to the remaining 822 patients. All tumors were located close to the lesser curvature. Conclusions The incidence of GIST found in this cohort is significantly higher than previously reported. This may be due to an association between these tumors and obesity or because asymptomatic GISTs are underdiagnosed in the general population. These tumors are particularly common in older patients and special attention must be given when performing LSG on this subpopulation. The stomach should be inspected thoroughly before resection. A tumor on the lesser curvature may necessitate changing the surgical plan or aborting the procedure. Keywords Gastrointestinal stromal tumor (GIST) . Sleeve . Gastrectomy . Bariatric
J. B. Yuval e-mail: [email protected] A. Khalaileh e-mail: [email protected]
Introduction
M. Abu-Gazala e-mail: [email protected]
Gastrointestinal stromal tumor (GIST) is a rare mesenchymal neoplasm of the alimentary tract [1]. This tumor is caused by specific gain of function mutations in the C-Kit (CD117), tyrosine kinase protein, or in platelet-derived growth factor receptor alpha (PDGFRα) [2, 3]. It has been proposed that GIST arises from the interstitial cell of Cajal, considered the pacemaker cells of the alimentary tract [4] . Cajal cells and GIST cells are similar histologically in exhibiting both neuronal and smooth muscle cell features in electron microscopy and immunohistochemistry[5].
Y. Shachar e-mail: [email protected] A. Keidar e-mail: [email protected] Y. Mintz e-mail: [email protected] A. Nissan e-mail: [email protected]
OBES SURG (2014) 24:2134–2137
Previous reports regarding the epidemiology of GIST described an incidence of 0.5 to 2 per 100,000 accounting for only 0.3–0.5 % of all gastrointestinal tumors [6, 7]. Data from autopsies, however, point out a tendency toward a higher incidence of 20 per 100,000 for clinically insignificant GISTs [7]. The majority of GISTs are diagnosed in patients 50 years of age or older [8]. There are reports of equal distribution between sexes or slight male predominance [4, 8]. GISTs can be found anywhere along the alimentary tract but are most commonly found in the stomach (60 %) followed by the small intestine (30 %), large bowel (5 %), and rectum (5 %)[1, 4, 6]. The clinical behavior of GIST following surgical resection is variable [9]. Even completely resected small tumors may recur locoregionally or metastasize. The National Institutes of Health (NIH) have developed a consensus scheme to evaluate the clinical course of GIST based on tumor size and mitotic index [10]. Complete surgical excision is the mainstay of treatment [11] and high risk lesions should be treated with adjuvant imatinib mesylate. Due to the worldwide epidemic of obesity, bariatric surgical procedures are becoming increasingly common [12]. Unlike Roux-en-Y gastric bypass (RYGB) and laparascopic adjustable gastric banding (LAGB), laparoscopic sleeve gastrectomy (LSG) provides pathological specimens of the majority of the stomach, the organ where GISTs are most commonly found. It is therefore interesting to examine the pathological reports of LSG in order to study the incidence and anatomical location of GIST in the obese population. The aim of this study was to describe the incidence of asymptomatic GISTs found during in a cohort of morbidly obese patients undergoing LSG in a single institution.
Materials We conducted a retrospective study using our prospectively collected data of our medical center's metabolic and bariatric registry approved by Institutional Ethical Committee (IEC, Helsinki Committee). We identified patients that underwent LSG in whom a GIST was found in the resected pathological specimen. Data collected included the following: gender, age, body mass index (BMI), and the existence of hypertension or type 2 diabetes mellitus. We also focused on the tumor parameters: location, size, mitotic index, and staining for C-kit, CD34, CD117, and PDGFRα. The group of patients diagnosed with GIST (GIST group) was compared to the rest of the patients (control group). We presented continuous variables as mean±standard deviation (SD), and statistical difference was calculated using the unpaired t test. Categorical variables were compared using the Fisher's exact test. Both types of variables were defined as statistically significant if the p value was less than 0.01 (Table 1).
2135 Table 1 Patients’ characteristics GIST group n=5
Control group n=822
p value
Gender (m/f) Age (years) BMI (kg/m2) T2DM (%)
4/1 55.4+7 36+2.2 60
1/2 39+12.2 42.4+5.2 19.7
