Intersphincteric resection and abdominoperineal resection offer similar oncologic outcomes

During the last several decades, the quest for sphincter preservation has continued to flourish around the globe. While low anterior resection was surpassed by coloanal anastomosis which has now in turn been trumped by intersphincteric resection as being able to offer a low anastomosis rather than a colostomy. However the mere ability to avoid a colostomy does not justify an intersphincteric resection if such a resection means a compromise to the oncologic outcome of the cancer operation. In order to test this hypothesis, Tsukamoto and coworkers from Tokyo, Japan evaluated 112 patients who underwent a curative intersphincteric resection and 173 patients who underwent an abdominoperineal resection. All patients had either stage I, II, or III distal rectal cancer and none of the patients underwent preoperative neoadjuvant chemo radiotherapy. The patients were well stratified by age, gender, BMI (which of course given that the study was performed in Japan was a median of approximately 22 throughout the study), CEA, tumor height (a median of between 2 cm to 3 cm in the groups), clinical depth, lymph node positivity, and circumferential resection margin (CRM) clearance. Although the operative times were approximately 30 minutes longer in the intersphincteric group there were no differences in blood loss, synchronous resections, the employment of lateral pelvic node dissection, or the employment adjuvant chemotherapy. The postoperative morbidity rate was significantly lower in the intersphincteric resection group at 17% as compared to 31.8% in the abdominoperineal resection group. Similarly the hospital stay was shorter at a median of 14 days in the intersphincteric resection group as compared to 18 days in the abdominoperineal resection group. The authors were unable to identify any differences between the groups in terms of tumor differentiation, T stage, lymph node positivity, number of nodes harvested, lymphatic invasion, venous invasion, or positive CRM. Very importantly the short term surrogate histopathologic variables correlated very well with the longer term recurrence and survival data. Specifically, three year cumulative local recurrence rates were 3.9% in the APR group and 7.3% in the intersphincteric group. Thus the authors concluded that intersphincteric resection and abdominoperineal resection offered similar oncologic outcomes. I applaud the authors upon producing this high quality study which helps us continue to justify sphincter preservation for distal tumors. However, it is critical that patient reported outcomes especially relevant to bowel function including frequency and continence be reported.