Predictors of Timely Initiation and Completion of Adjuvant Chemotherapy in Stage II/III Colorectal Adenocarcinoma.

Background: Adjuvant chemotherapy (AC) for colorectal cancer (CRC) has led to substantial improvement in survival. Several clinical trials advocate the initiation of AC within 6-8 weeks of surgical resection based on evidence of improved survival with early initiation of AC. We aim to evaluate factors that predict initiation and completion of AC, subsequently improving survival. Methods: We identified 451 patients who underwent resection for CRC between 2014 and 2022. One hundred ten patients had stage II/III colorectal cancer who underwent resection followed by AC. Multivariable logistic regression analysis was performed to identify factors significantly predicting delay in AC >8 weeks. Secondary outcomes included chemotherapy completion rate, recurrence-free survival, and overall survival. Results: The final analysis included 110 patients. The median time to initiation of adjuvant chemotherapy (TIAC) was 6.9 weeks (IQR: 5.8-9.5). In total, 36.4% of patients had a delay >8 weeks to initiation of AC, and only 40% completed treatment. The surgical approach (open vs laparoscopic vs robotic) had no effect on the TIAC. On multivariable logistic regression analysis, preoperative albumin ≥3.5 (OR = .31; 95% CI: .12-.80) was an independent predictor of timely initiation of AC. Completion of AC was associated with a higher overall survival. Discussion: Preoperative nutritional status predicted delay in initiation of AC. Patients with a delay in AC beyond eight weeks had a lower rate of AC completions and worse survival. It is imperative to optimize this aspect of treatment as it correlates with survival.