• Guilherme P São Julião, Georgios Karagkounis, Laura M Fernandez, Angelita Habr-Gama, Bruna B Vailati, Mit Dattani, Matthew F Kalady, and Rodrigo O Perez.
• Angelita & Joaquim Gama Institute, Sao Paulo, Brazil.
• Ann. Surg. 2020 Jul 1; 272 (1): 138-144.

ObjectiveAnalyze conditional recurrence-free survival (cRFS) for rectal cancer patients with complete clinical response (cCR) after neoadjuvant chemoradiation (nCRT) managed nonoperatively after each year without recurrence.Summary Background DataSelect patients with cCR after nCRT have been managed nonoperatively. Risk factors for local recurrence, the need for prolonged follow-up, and the risk of recurrence over time are not well defined.MethodsRetrospective review of patients with rectal cancer cT2-4N0-2M0 treated with nCRT. Mean follow-up was 64 months. Patients who achieved cCR were managed nonoperatively. cRFS was used to investigate the evolution of recurrence-odds, as patients remain recurrence-free after completion of nCRT. Three-year cRFS was estimated at "x" years after completion of nCRT based on the formula cRFS3 = RFS(x+3)/RFS(x).ResultsOne hundred ninety-seven patients with cCR after nCRT were included. Overall survival and recurrence-free survival (RFS) at 5 years were 81.9% (95% CI 74.0%-87.6%) and 60.4% (95% CI 52.5%-67.4%) respectively. Using cRFS estimates, the probability of remaining disease-free for an additional 3 years if the patient survived without disease at 1, 3, and 5 years, was 77.4% (95% CI 68.8%-83.8%), 91.0% (95% CI 81.9%-95.7%), and 94.3% (95% CI 82.9%-98.2%), respectively. In contrast, actuarial RFS rates for similar intervals were 79.1% (95% CI 72.5%-84.2%), 64.2% (95% CI 56.5%-70.8%), and 60.4% (95% CI 52.5%-67.4%). After 2 years disease-free, 3 year cRFS became similar for T2 and T3 cancers. In contrast, patients undergoing extended nCRT became less likely to develop recurrences only after initial 2 years of successful organ-preservation.ConclusionsConditional survival suggests that patients have significantly lower risks (≤10%) of developing recurrences after 2 years of achieving cCR following nCRT.

15 keywords...

hide…