Impact of adjuvant chemotherapy on survival in ypT0-2 N0 rectal cancer

Purpose: The role of adjuvant chemotherapy in rectal cancer patients downstaged to ypT0-2 N0 after neoadjuvant chemoradiotherapy (CRT), and surgery is still debated. This study investigates the impact of adjuvant chemotherapy on survival outcomes in this patient population.

Methods: This retrospective study analyzed hospital records of rectal cancer cases from Shefa Al Orman Cancer Hospital between January 2016 and December 2020, focusing on patients downstaged to ypT0-2 N0 after neoadjuvant CRT and surgery. Patients were divided into two groups based on whether they received adjuvant chemotherapy. Baseline characteristics, DFS, and OS were compared, and survival factors were analyzed using univariate and multivariate Cox regression.

Results: Eighty-five patients met the inclusion criteria; 55 received adjuvant chemotherapy, and 30 did not. The median age was 52, but those receiving adjuvant therapy were younger (47 vs. 60 years, P = 0.006). No significant differences were observed in sex, tumor location, or pathology between groups. Although adjuvant chemotherapy showed a trend toward better 3-year DFS (89.5% vs. 81.9%, P = 0.153) and OS (88.1% vs. 84.6%, P = 0.654), these differences were not statistically significant. Univariate and multivariate analyses confirmed no significant effect of adjuvant chemotherapy on DFS or OS, nor were any other variables significantly associated with survival.

Conclusion: Adjuvant chemotherapy did not significantly improve DFS or OS in rectal cancer patients downstaged to ypT0-2 N0 following neoadjuvant CRT and surgery. Further studies are needed to define the role of adjuvant therapy in this group.