LETTER TO THE EDITOR Clinical Value of Preoperative Chest Computed Tomography for Colon Cancer Under Current Knowledge and Imaging Technology To the Editor: e read with interest the article by Kim et al1 reporting on the clinical value of preoperative chest computed tomography (CT) in patients with colon cancer. The authors concluded that preoperative staging chest CT was not routinely commended in colon cancer patients without liver metastasis and lymph node metastasis suggested on abdominal and pelvic CT who had negative findings on initial chest X-ray (CXR). However, we would like to make some comments on the necessity of routine preoperative chest CT in patients with colon cancer. Pulmonary imaging for metastases is considered as a routine part of preoperative staging in patients with colorectal cancer. However, selection of optimal staging strategy for determination of pulmonary metastases has been controversial. CXR was not indicated as a routine preoperative staging modality because of its low sensitivity to pulmonary metastases,2 and naturally the low detection rate of pulmonary metastases will seldom change overall patient management. On the contrary, preoperative chest CT was recommended by most guidelines based on improved sensitivity over CXR in the detection of pulmonary metastases.3,4 For the patients with colon cancer without liver metastases, Kim et al1 reported an incidence of 6.3% pulmonary metastases, which is consistent with that of most of studies with identical patient inclusion criteria, and comparable to some series reporting the overall incidence of colorectal pulmonary metastases. Detection of pulmonary metastases may change the management, at least in selected patients. Therefore, we agree with the view of Tan et al5 that a preoperative search for pulmonary metastases should be not excluded in these patients. However, the value of preoperative CT was questioned because of less specificity, which results in the uncertainty in interpretation of the significance of indeterminate le-
W
Disclosure: No potential conflicts of interest were disclosed. C 2015 Wolters Kluwer Health, Inc. All Copyright rights reserved. ISSN: 0003-4932/15/26201-e0013 DOI: 10.1097/SLA.0000000000000413
sions. Furthermore, no evidence reports the superiority of positron emission tomography (PET) or PET/CT over CT for the detection of pulmonary metastases or characterization of indeterminate lung lesions.6,7 For these indeterminate lung lesions, when no more effective imaging modality is available and routine pathological biopsy is unpractical in most of case, the usefulness of routine preoperative chest CT to compare against postoperative chest CT may facilitate interpretation of further tests for the suspicious case. In summary, preoperative pulmonary imaging by CT for individual patients not only should be used as a sole preoperative staging modality but also could be utilized to a baseline reference for indeterminate pulmonary lesions or initial imaging evidence for emerging pulmonary lesions to contrast with postoperative chest CT in the current environment of rather limited knowledge and technology. In this sense, preoperative chest CT is more important in postoperative reference than preoperative staging. The adherence to query the role of chest CT in the preoperative pulmonary staging may result in throwing away the baby with the bath water. Wen-Jian Meng, MD, PhD Zi-Qiang Wang, MD, PhD Zong-Guang Zhou, MD, PhD, FACS Department of Gastrointestinal Surgery West China Hospital, Sichuan University Chengdu, China [email protected] and [email protected] Chao Tian, MD Department of General Surgery Sichuan Cancer Hospital Chengdu, China
REFERENCES 1. Kim HY, Lee SJ, Lee G, et al. Should preoperative chest CT be recommended to all colon cancer patients? Ann Surg. 19 February 2013. [ePub ahead of print] 2. Australian Cancer Network Colorectal Cancer Guidelines Revision Committee. Guidelines for the Prevention, Early Detection and Management of Colorectal Cancer. Sydney, Australia: The Cancer Council Australia and Australian Cancer Network; 2005. Available at: http://www.nhmrc.gov.au/ files nhmrc/publications/attachments/cp106 0.pdf. Accessed March 20, 2013. 3. The Association of Coloproctology of Great Britain and Ireland. Guidelines for the Management of Colorectal Cancer. 3rd ed. London, UK: The Association of Coloproctology of Great Britain and Ireland; 2007. Available at: http://www.mccn.nhs .uk/userfiles/documents/Nat%20Ass%20of%20 Coloproctology%20Guidelines(1).pdf. Accessed March 20, 2013. 4. NCCN Guidelines Version 2. 2012 Panel Members Colon Cancer. NCCN Clinical Practice Guidelines in Oncology. Colon Cancer. NCCN Cancer panel members, National Comprehensive
Annals of Surgery r Volume 262, Number 1, July 2015
Cancer Network. (2012, 2nd Version). Available at: http://www.nccn.org/professionals/physician_gls/ f_guidelines.asp. Accessed March 20, 2013. 5. Tan KK, Lopes Gde L, Jr, Sim R. How uncommon are isolated lung metastases in colorectal cancer? A review from database of 754 patients over 4 years. J Gastrointest Surg. 2009;13:642–648. 6. Furukawa H, Ikuma H, Seki A, et al. Positron emission tomography scanning is not superior to whole body multidetector helical computed tomography in the preoperative staging of colorectal cancer. Gut. 2006;55:1007–1011. 7. Parnaby CN, Bailey W, Balasingam A, et al. Pulmonary staging in colorectal cancer: a review. Colorectal Dis. 2012;14:660–670.
Reply:
W
e would like to thank Dr Meng and colleagues for their interest in our study1 and their kind letter. First, we agree with the comment that chest computed tomography (CT) have improved sensitivity over chest Xrays. However, the investigation of accuracy of chest CT was not the purpose of our study. We focused on the usefulness of preoperative chest CT in colon cancer patients without liver metastasis who had negative findings on initial chest X-ray. Routine preoperative chest CT is recommended in several guidelines, but, surprisingly, there has been a paucity of data concerning the efficacy as we described. According to our results, all the patients with isolated lung metastasis were CTpredicted stage T3 or T4 and 95% of the patients with isolated lung metastasis were CT-predicted stage N1 or N2. Therefore, we thought that the usefulness of preoperative chest CT is very low in colon cancer patients with abdominal and pelvic CT-predicted stage T1-2, N0, and M0. Unnecessary CT scan can cause unnecessary radiation exposure and unnecessary cost for the CT scan itself and the additional tests to confirm the abnormal finding. Of course, we are looking forward to further studies to support our results as there were few studies about risk factors of isolated lung metastasis in colon cancer. And, the preoperative usefulness of chest CT in colon cancer patients with advanced T stage or nodal metastasis and in rectal cancer is another story. Second, we agree with the comment that routine preoperative chest CT is useful when it is compared against postoperative chest CT in the patients with indeterminate lung nodules. However, it has been reported that the progression of intermediate lung nodules into metastases was related to nodal metastasis.2,3 Therefore, it is questionable whether preoperative chest CT is useful as a baseline reference for indeterminate lung Disclosure: The authors declare no conflicts of interest. 10.1097/SLA.0000000000000412
www.annalsofsurgery.com | e13
Copyright © 2015 Wolters Kluwer Health, Inc. Unauthorized reproduction of this article is prohibited.
Annals of Surgery r Volume 262, Number 1, July 2015
nodules in colon cancer patients without nodal metastasis. We don’t perform bone scan as a baseline reference for low possibility of bone metastasis. We believe that our study is helpful, especially when we see the real individual patient with early colon cancer although more large-scale studies are needed. Most of guidelines are designed to provide information to assist in decision-making and are subject to the clinician’s judgment and the patient’s preference in each individual case. Hye Young Kim, MD Department of Medicine Samsung Medical Center
e14 | www.annalsofsurgery.com
Sungkyunkwan University School of Medicine Seoul, Korea Soon Jin Lee, MD, PhD Department of Radiology Samsung Medical Center Sungkyunkwan University School of Medicine Seoul, Korea Young-Ho Kim, MD, PhD Department of Medicine Samsung Medical Center Sungkyunkwan University School of Medicine
Seoul, Korea [email protected]
REFERENCES 1. Kim HY, Lee SJ, Lee G, et al. Should Preoperative chest CT be recommended to all colon cancer patients? Ann Surg. 19 February 2013. [ePub ahead of print] 2. Brent A, Talbot R, Coyne J, et al. Should indeterminate lung lesions reported on staging CT scans influence the management of patients with colorectal cancer? Colorectal Dis. 2007;9:816–818. 3. Christoffersen MW, Bulut O, Jess P. The diagnostic value of indeterminate lung lesions on staging chest computed tomographies in patients with colorectal cancer. Dan Med Bull. 2010;57:A4093.
C 2015 Wolters Kluwer Health, Inc. All rights reserved.
Copyright © 2015 Wolters Kluwer Health, Inc. Unauthorized reproduction of this article is prohibited.
W
Disclosure: No potential conflicts of interest were disclosed. C 2015 Wolters Kluwer Health, Inc. All Copyright rights reserved. ISSN: 0003-4932/15/26201-e0013 DOI: 10.1097/SLA.0000000000000413
sions. Furthermore, no evidence reports the superiority of positron emission tomography (PET) or PET/CT over CT for the detection of pulmonary metastases or characterization of indeterminate lung lesions.6,7 For these indeterminate lung lesions, when no more effective imaging modality is available and routine pathological biopsy is unpractical in most of case, the usefulness of routine preoperative chest CT to compare against postoperative chest CT may facilitate interpretation of further tests for the suspicious case. In summary, preoperative pulmonary imaging by CT for individual patients not only should be used as a sole preoperative staging modality but also could be utilized to a baseline reference for indeterminate pulmonary lesions or initial imaging evidence for emerging pulmonary lesions to contrast with postoperative chest CT in the current environment of rather limited knowledge and technology. In this sense, preoperative chest CT is more important in postoperative reference than preoperative staging. The adherence to query the role of chest CT in the preoperative pulmonary staging may result in throwing away the baby with the bath water. Wen-Jian Meng, MD, PhD Zi-Qiang Wang, MD, PhD Zong-Guang Zhou, MD, PhD, FACS Department of Gastrointestinal Surgery West China Hospital, Sichuan University Chengdu, China [email protected] and [email protected] Chao Tian, MD Department of General Surgery Sichuan Cancer Hospital Chengdu, China
REFERENCES 1. Kim HY, Lee SJ, Lee G, et al. Should preoperative chest CT be recommended to all colon cancer patients? Ann Surg. 19 February 2013. [ePub ahead of print] 2. Australian Cancer Network Colorectal Cancer Guidelines Revision Committee. Guidelines for the Prevention, Early Detection and Management of Colorectal Cancer. Sydney, Australia: The Cancer Council Australia and Australian Cancer Network; 2005. Available at: http://www.nhmrc.gov.au/ files nhmrc/publications/attachments/cp106 0.pdf. Accessed March 20, 2013. 3. The Association of Coloproctology of Great Britain and Ireland. Guidelines for the Management of Colorectal Cancer. 3rd ed. London, UK: The Association of Coloproctology of Great Britain and Ireland; 2007. Available at: http://www.mccn.nhs .uk/userfiles/documents/Nat%20Ass%20of%20 Coloproctology%20Guidelines(1).pdf. Accessed March 20, 2013. 4. NCCN Guidelines Version 2. 2012 Panel Members Colon Cancer. NCCN Clinical Practice Guidelines in Oncology. Colon Cancer. NCCN Cancer panel members, National Comprehensive
Annals of Surgery r Volume 262, Number 1, July 2015
Cancer Network. (2012, 2nd Version). Available at: http://www.nccn.org/professionals/physician_gls/ f_guidelines.asp. Accessed March 20, 2013. 5. Tan KK, Lopes Gde L, Jr, Sim R. How uncommon are isolated lung metastases in colorectal cancer? A review from database of 754 patients over 4 years. J Gastrointest Surg. 2009;13:642–648. 6. Furukawa H, Ikuma H, Seki A, et al. Positron emission tomography scanning is not superior to whole body multidetector helical computed tomography in the preoperative staging of colorectal cancer. Gut. 2006;55:1007–1011. 7. Parnaby CN, Bailey W, Balasingam A, et al. Pulmonary staging in colorectal cancer: a review. Colorectal Dis. 2012;14:660–670.
Reply:
W
e would like to thank Dr Meng and colleagues for their interest in our study1 and their kind letter. First, we agree with the comment that chest computed tomography (CT) have improved sensitivity over chest Xrays. However, the investigation of accuracy of chest CT was not the purpose of our study. We focused on the usefulness of preoperative chest CT in colon cancer patients without liver metastasis who had negative findings on initial chest X-ray. Routine preoperative chest CT is recommended in several guidelines, but, surprisingly, there has been a paucity of data concerning the efficacy as we described. According to our results, all the patients with isolated lung metastasis were CTpredicted stage T3 or T4 and 95% of the patients with isolated lung metastasis were CT-predicted stage N1 or N2. Therefore, we thought that the usefulness of preoperative chest CT is very low in colon cancer patients with abdominal and pelvic CT-predicted stage T1-2, N0, and M0. Unnecessary CT scan can cause unnecessary radiation exposure and unnecessary cost for the CT scan itself and the additional tests to confirm the abnormal finding. Of course, we are looking forward to further studies to support our results as there were few studies about risk factors of isolated lung metastasis in colon cancer. And, the preoperative usefulness of chest CT in colon cancer patients with advanced T stage or nodal metastasis and in rectal cancer is another story. Second, we agree with the comment that routine preoperative chest CT is useful when it is compared against postoperative chest CT in the patients with indeterminate lung nodules. However, it has been reported that the progression of intermediate lung nodules into metastases was related to nodal metastasis.2,3 Therefore, it is questionable whether preoperative chest CT is useful as a baseline reference for indeterminate lung Disclosure: The authors declare no conflicts of interest. 10.1097/SLA.0000000000000412
www.annalsofsurgery.com | e13
Copyright © 2015 Wolters Kluwer Health, Inc. Unauthorized reproduction of this article is prohibited.
Annals of Surgery r Volume 262, Number 1, July 2015
nodules in colon cancer patients without nodal metastasis. We don’t perform bone scan as a baseline reference for low possibility of bone metastasis. We believe that our study is helpful, especially when we see the real individual patient with early colon cancer although more large-scale studies are needed. Most of guidelines are designed to provide information to assist in decision-making and are subject to the clinician’s judgment and the patient’s preference in each individual case. Hye Young Kim, MD Department of Medicine Samsung Medical Center
e14 | www.annalsofsurgery.com
Sungkyunkwan University School of Medicine Seoul, Korea Soon Jin Lee, MD, PhD Department of Radiology Samsung Medical Center Sungkyunkwan University School of Medicine Seoul, Korea Young-Ho Kim, MD, PhD Department of Medicine Samsung Medical Center Sungkyunkwan University School of Medicine
Seoul, Korea [email protected]
REFERENCES 1. Kim HY, Lee SJ, Lee G, et al. Should Preoperative chest CT be recommended to all colon cancer patients? Ann Surg. 19 February 2013. [ePub ahead of print] 2. Brent A, Talbot R, Coyne J, et al. Should indeterminate lung lesions reported on staging CT scans influence the management of patients with colorectal cancer? Colorectal Dis. 2007;9:816–818. 3. Christoffersen MW, Bulut O, Jess P. The diagnostic value of indeterminate lung lesions on staging chest computed tomographies in patients with colorectal cancer. Dan Med Bull. 2010;57:A4093.
C 2015 Wolters Kluwer Health, Inc. All rights reserved.
Copyright © 2015 Wolters Kluwer Health, Inc. Unauthorized reproduction of this article is prohibited.
