Invited comment on Warrier et al.: hereditary colorectal cancer screening and management practices by colorectal surgeons
Despite a low survey response rate of 10 % and the potential for non-response bias, the Warrier study in this month’s issue raises significant issues about genetic evaluation and surgical management in young patients suspected of having hereditary colorectal cancer (CRC)/polyposis syndromes . Perhaps most important is the fact that there is great heterogeneity among colorectal surgeons in the preoperative, operative and postoperative management practices of these patients. For example, in patients with CRC under age 50 without a family history of CRC, 33.1 % of surgeons would proceed to definitive surgery without a preoperative genetic evaluation, while 48.9 % would request some form of tumor analysis to help risk stratify the patient. In this latter group, there was again significant heterogeneity with differing practices regarding the ordering of microsatellite instability (MSI), immunohistochemistry (IHC) or combination (MSI/IHC) testing. The key question, which is not answered by this study, is what underlies the difference in approach among surgeons. As the National Comprehensive Cancer Network (NCCN) guidelines recommend mismatch repair (MMR) protein testing in all patients with CRC under the age of 50, regardless of family history, it would be important to distinguish whether the surveyed physicians are not aware of this recommendation or simply disagree with the recommendation and chose not follow it . The former may signify a lack of provider education. With the later, it would be important to ascertain the physician-related factors associated with medical decision making in this high-risk patient group (e.g., the belief that there is an inadequate evidence base upon which to build a recommendation). Alternatively, there may be patient-related factors, including patient preference, insurance status and concerns of being labeled as having a genetic disease, which can either facilitate or impede effective management. For example, with regard to patient preference, some individuals may be unwilling to wait for tumor analysis or formal genetic testing results and desire surgery immediately. Clearly, in all cases, an important goal should be to better understand the driving forces and obstacles that underlie medical decision making. This will help create standardized patient care practices and may ultimately optimize clinical outcomes.
Also of particular interest in the study was provider reliance on family history to decide which patients would be eligible for preoperative genetic testing, to determine extent of colonic resection and to guide postoperative surveillance. Unfortunately, this approach has many pitfalls as a significant proportion of patients may have de novo mutations and hence will lack a family history of cancer . In addition, although it has been traditionally accepted that Lynch syndrome patients develop cancer in their forties, recent evidence has shown that the average age of diagnosis may be in the early sixties . Hence, penetrance can vary widely, and some family members may not live long enough to manifest the malignant phenotype. This, of course, would make reliance on family history fraught with difficulty.
Finally, it should be noted that gastroenterologists can play a key role in the preoperative work-up of young patients with colorectal cancer. Although colorectal surgeons perform large numbers of diagnostic preoperative colonoscopies, the majority of colonoscopies are done by gastroenterologists. The authors state that testing of tumor tissue preoperatively for MSI/IHC can facilitate medical decision making and guide the extent of surgical resection. Gastroenterologists, who in most cases would be the first to diagnose a colonic malignancy, would be in an ideal position to assist their surgical colleagues by initiating molecular testing of tumor tissue and referring patients for a formal genetics evaluation, as needed, prior to the surgical visit. This would allow surgeons to have important clinical information available in the preoperative setting, which would help optimize patient management.
Conflict of interest
- 1.Warrier SK, Kalady MF, Kiran RP, Church JM (2013) Results from an American society of colon and rectal surgeons survey on the management of young-onset colorectal cancer. Tech Coloproctol. doi:10.1007/s10151-013-1052-5
- 2.National Comprehensive Cancer Network (2013) NCCN guidelines: colon cancer. http://www.nccn.org/professionals/physician_gls/f_guidelines.asp. Accessed 1 Aug 2012
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