OBJECTIVETo summarize and analyze the clinicopathological features and surgical management of patients with pathologic complete response (pCR) in the primary tumor after neoadjuvant chemotherapy for rectal cancer, and to explore the rational treatment of this entity.

METHODSClinical data of fifty-two patients with locally advanced mid-low rectal cancer admitted to the Cancer Institute and Hospital, Chinese Academy of Medical Sciences from January 1994 to December 2013 were retrospectively analyzed. They were treated with neoadjuvant chemotherapy and achieved pathological complete response in the primary tumor. The preoperative clinical staging were stage II (cT3~4N0) in 10 cases and stage III (cT3~4N+) in 42 cases. After the neoadjuvant therapy, 10 cases achieved clinical complete response (cCR) (19.2%).

RESULTSRadical surgery was performed in 51 patients. Among them, five patients (9.8%) had pathological lymph node metastasis. One cCR patient underwent transanal local excision. The postoperative complication rate was 21.2%. During a median follow-up of 23.6 months, only one patient developed bone metastasis and another one had enlarged mesenteric and retroperitoneal lymph nodes detected by imaging. All the patients were alive by the last follow-up. The 2-year disease-free survival rate was 96.2% and overall survival rate was 100%.

CONCLUSIONSRadical surgery remains the standard therapy for cCR patients with rectal cancer after neoadjuvant chemotherapy. Local excision and "wait and see" should be recommended with great caution and limited to patients who cannot tolerate or refuse radical surgery with a strong demanding for sphincter saving, or applied in clinical trials.