Local recurrence after five years is associated with preoperative chemoradiotherapy treatment in patients diagnosed with stage II and III rectal cancer.

AIM: To asses the moment of local recurrence and its influence on the appraisal of the results of neoadjuvant chemoradiotherapy (CRT).

METHODS: We evaluated 317 patients with a preoperative diagnosis of stage II or III rectal cancer who underwent rectal resection. Gender, age, neoadjuvant treatment, circumferencial resection margin, adjuvant treatment, pretreatment carcinoembryonic antigen level, tumor location, TNM stage, lymph node retrieval, abdominoperineal resection, and lymphatic or vascular infiltration were registered prospectively. Follow-up was performed to detect local or systemic recurrences. Timing of local recurrence (LR) in regard to analyzed variables was performed by using analysis of variance. To evaluate the influence of late local recurrence (LLR) on the results of neoadjuvant CRT, we performed a log-rank test censoring all observations at 60 and at 120 months.

RESULTS: After a mean follow-up of 73.6 months (range, 1-171), 68 patients developed a recurrence. Twenty-three patients developed LRs (6.9%), and 5 developed LLRs. The earliest relapse was diagnosed 4 months after rectal surgery, and the latest was diagnosed 120 months after surgery. Patients who underwent neoadjuvant CRT developed LR significantly later than patients without neoadjuvant CRT (51.8 vs 13.5 months; P = 0.002). LR rates in patients who underwent preoperative CRT and those who did not were 9.2% and 3.5% (difference, 5.7%), respectively, after censoring all observations at 60 months and 9.2% and 6.1% (difference, 3.1%) after censoring all observations at 120 months.

CONCLUSION: Local recurrence was diagnosed significantly later in patients treated with neoadjuvant CRT. Follow-up longer than 5 years is needed to evaluate definitive results in patients treated with neoadjuvant CRT.