Tumor Resectability and Pathologic Response After Neoadjuvant Long-Course Chemoradiotherapy for Locally Advanced Rectal Cancer in a Resource-Limited Setting

Purpose In resource-limited settings, locally advanced rectal cancer (LARC) often presents at advanced stages. Long-course chemoradiotherapy (LCCRT) remains a cornerstone of neoadjuvant therapy, yet outcome data from such settings remain limited. This study assessed tumor resectability, pathologic response, and factors associated with resectability following neoadjuvant LCCRT at Ethiopias largest tertiary oncology center. Methods A retrospective cohort study was conducted among patients with stage II-III rectal adenocarcinoma (cT3-4 and/or cN+) who completed neoadjuvant LCCRT at Tikur Anbessa Specialized Hospital between 2018 and 2023. Tumor resectability was determined by multidisciplinary team (MDT) assessment. Multivariable logistic regression was used to identify factors associated with post-LCCRT resectability, adjusting for initial T stage, circumferential resection margin (CRM) status, histologic subtype, radiotherapy technique, and neoadjuvant regimen. Results Among 58 eligible patients (median age 45 years; 62% male), 62% had cT4 tumors, 53% had cN2 disease, and 84.5% had involved CRM. The median diagnosis-to-LCCRT interval was 64 weeks (interquartile range [IQR], 37-82). After LCCRT, 27 patients (46.6%) were deemed resectable by MDT assessment; 19 patients (32.8%) ultimately underwent curative-intent surgery (median interval from LCCRT to surgery, 10 weeks; IQR, 7-15). Initial cT3 stage was associated with higher odds of resectability (adjusted odds ratio [AOR], 6.2; 95% CI, 1.06-36.37), whereas receipt of total neoadjuvant therapy was associated with lower odds (AOR, 0.10; 95% CI, 0.02-0.49). No pathologic complete responses were observed. Conclusion In this cohort characterized by advanced disease at presentation and treatment delays, neoadjuvant LCCRT resulted in low resectability and limited pathologic response. To enhance curative potential, concerted efforts are needed to expedite the timely initiation of radiotherapy, optimize multidisciplinary team assessment, and increase surgical capacity.