<b><i>Background/Aim:</i></b> Neoadjuvant chemoradiation (nCRT) in rectal cancer is associated with significant long-term morbidity. It is unclear whether nCRT in resectable mesorectal fascia circumferential resection margin (mrCRM)-negative rectal cancer treated by adequate total mesorectal excision (TME) is beneficial. The aim was to determine if nCRT can be omitted in patients with MRI-assessed cT3 rectal cancer and a negative mrCRM undergoing good-quality TME. <b><i>Methods:</i></b> By means of a prospective nationwide registry (<i>n</i> = 43.147; prospective multi-center observational study), patients with cT3 rectal cancer <12 cm from the anal verge with a negative (>1 mm) MRI-assessed CRM undergoing radical resection from 2006 to 2008 were selected. Overall, 87 patients were available for the final analysis (TME-alone, <i>n</i> = 25; nCRT+TME, <i>n</i> = 62). Groups were balanced for age, sex, and ASA score, with a nonsignificant predominance of males in the nCRT+TME group. As main outcome measures, local and distant recurrence rates were compared between patients undergoing primary surgery (TME-alone) vs. neoadjuvant chemoradiation + surgery (nCRT+TME). <b><i>Results:</i></b> In the TME-alone group, tumors were located closer to the anal verge (<i>p</i> = 0.018) and demonstrated a smaller minimal circumferential distance from the resection margin (<i>p</i> = 0.036). TME quality was comparable, as was median follow-up (48.9 vs. 44.9 months; <i>p</i> = 0.268). Local recurrences occurred at a similar rate in the TME-alone (<i>n</i> = 1; 5.3%) and nCRT+TME groups (<i>n</i> = 3; 5.5%) (<i>p</i> = 0.994) and were diagnosed at 10 months (TME-alone) and at 8, 13, and 18 months (nCRT+TME). Distant recurrences occurred in 28.9 and 17.4% of the cases, respectively (<i>p</i> = 0.626). The analysis was limited to cT3 cancers with a negative mrCRM. In addition, caution is required when appraising these results because of the limited number of evaluable subjects (especially in the TME-alone group), which adds some uncertainty to the statistical analysis. <b><i>Conclusions:</i></b> In this cohort of patients with rectal cancer located <12 cm from the anal verge and a negative mrCRM undergoing adequate TME, omission of nCRT had no impact onto the local recurrence rate.
Risk factors for locoregional recurrence in patients with pathologic T3N0 rectal cancer with negative resection margin treated by surgery alone
