Nonoperative management of rectal cancer with complete clinical response after neoadjuvant therapy.

INTRODUCTION Nonoperative management (NOM) of rectal cancer after a complete clinical response (cCR) to neoadjuvant therapy is controversial. In this article, we retrospectively reviewed the outcomes of patients managed with selective NOM after a cCR to neoadjuvant treatment and compared these with patients who underwent standard rectal resection with a pathological complete response (pCR). METHODS Patients completing neoadjuvant chemoradiotherapy (CRT) for stage I to III rectal cancer between January 2006 and August 2010 were retrospectively reviewed. Median follow-up was calculated in months after completion of CRT. RESULTS Thirty-two patients (median follow-up 28 months) were treated by NOM after a cCR. Among 265 treated by CRT and rectal resection, 57 patients (22%) had a pCR and formed the control group (median follow-up 43 months). Factors associated with selective use of NOM included lower pretreatment stage, older age, and distal tumor location (P < 0.05). In the NOM group, 6 recurred locally (median 11 months, range 7-14), 3 of whom also had concurrent distant recurrence. All 6 local failures were controlled by salvage rectal resection with no further local recurrence of disease (median follow-up 17 months). In the rectal resection/pCR group, there were no local failures. The 2-year distant disease-free survival (88% vs 98%, P = 0.27) and overall survival (96% vs 100%, P = 0.56) were similar for NOM and rectal resection/pCR groups. CONCLUSIONS Rectal resection was successfully avoided in 81% of patients selected for NOM. When combined with salvage surgery, NOM appears to achieve similar local and distant disease control compared with patients with a pCR treated by rectal resection. Longer follow-up and prospective trials are warranted to evaluate this promising treatment option.