Is local excision after complete pathological response to neoadjuvant chemoradiation for rectal cancer an acceptable treatment option?

PURPOSE

The role of local excision in patients with good histological response to neoadjuvant chemoradiation for locally advanced rectal cancer is unclear, mainly because of possible regional nodal involvement. This study aims to evaluate the correlation between pathological T and N stages following neoadjuvant chemoradiation for locally advanced rectal cancer and the outcome of patients with mural pathological complete response undergoing local excision.

METHODS

This investigation was conducted as a retrospective analysis. Between January 1997 and December 2007, 320 patients with T3 to 4Nx, TxN+ or distal (≤ 6 cm from the anus) T2N0 rectal cancer underwent neoadjuvant concurrent chemoradiation followed by surgery. Radiotherapy was standard and chemotherapy consisted of common fluoropyrimidine-based regimens.

RESULTS

After chemoradiation, 93% patients had radical surgery, 6% had local excision, and 3% did not have surgery. In the 291 patients undergoing radical surgery, the pathological T stage correlated with the N stage (P = .036). We compared the outcome of patients with mural complete pathological response (n = 37) who underwent radical surgery (group I) and those (n = 14) who had local excision only (group II). With a median follow-up of 48 months, 4 patients in group I had a recurrence and none in group II had a recurrence; one patient died in group I and none died in group II. Disease-free survival, pelvic recurrence-free survival, and overall survival rates were similar in both groups.

CONCLUSION

In this retrospective study, nodal metastases were rare in patients with mural complete pathological response following neoadjuvant chemoradiation (3%), and local excision did not compromise their outcome. Therefore, local excision may be an acceptable option in these patients.