Real-World Data on the Practice of Chemoradiation with Select Cohort Consolidation Chemotherapy in High-Risk Locally Advanced Rectal Cancers (SOLAR study).

Objectives: Chemoradiation with capecitabine radiotherapy (Cape-RT) has been the standard of care as neoadjuvant treatment in locally advanced rectal cancer (LARC) for more than a decade. However, total neoadjuvant therapy has recently emerged as an alternative with the potential to impact survival outcomes; baseline outcomes with Cape-RT in real-world practice in the Indian context are not well known. Material and Methods: Treatment-naive patients with adenocarcinoma on histology and clinical-radiologically diagnosed LARC who received Cape-RT from June 2014 to December 2021 after multidisciplinary discussion were included. Patients received a long course of conventionally fractionated external beam RT (45-50 Gy in 25#) with concurrent oral capecitabine at a dose of 1650 mg/m Results: A total of 1,189 patients with a median age of 49 years (range: 15-95) were identified and included. A significant proportion of patients had high-risk characteristics, such as T3/T4 disease (94%) and node positivity (90%), and they involved circumferential resection margin (CRM) (51%) at baseline. Signet ring and mucinous histology were seen in 13 and 11% of patients. Two hundred and seventy-six patients (23%) required further consolidation chemotherapy (commonly CAPOX [capecitabine-oxaliplatin] or modified FOLFIRINOX [5-fluorouracil-leucovorin-irinotecan-oxaliplatin]) post-Cape-RT prior to attempting surgery due to either persistent CRM positivity, clinical T4 disease, prostate abutment, sphincter involvement (248 patients, 21%), or extensive bulky disease with poor response (12 patients, 1%). Overall, 14 patients (6%) had an interruption in RT and 22 (8%) in chemotherapy. Post-Cape-RT, with or without chemotherapy, 945 patients (79%) underwent TME. Chemotherapy post-TME was administered in 808 patients (78%). With a median follow-up of 54 months (range: 51.2-57.2), the 3- and 5-year EFS for the entire cohort was 73.2% (95% confidence interval [CI]: 70.6-75.8) and 64.3% (95% CI: 61.1-67.5), respectively, while the estimated 3- and 5-year OS was 81.3% (95% CI: 78.9-83.7) and 73% (95% CI: 70-76), respectively. On multivariate analysis, the presence of higher T stage ( Conclusion: Real-world data in a less-resourced setting concurs with published prospective and Western real-world data. This provides confidence in implementing consolidation chemotherapy in total neoadjuvant settings in countries with fewer resources.