Main Session
Sep
28
SS 14 - Now Is a STELLAR Time to TORCH Colorectal Cancer
167 - Comparison of Treatment Outcome Between Short-Course Total Neoadjuvant Therapy vs. Neoadjuvant Long-Course Chemoradiotherapy Alone in Locally Advanced Rectal Adenocarcinoma: A Phase III Randomized Controlled Trial
Presenter(s)
Sandip Kumar Barik, MD, MBBS - All India institute of medical Sciences , Bhubaneswar, Bhubaneswar, Odisha
S. K. K. Barik1, P. Mukherjee2, A. Mahajan3, D. K. Das4, S. K. D. Majumdar4, S. Mondal4, D. K. Muduly5, T. S. Mishra4, P. Sasmal4, B. Pattnaik4, B. Sahoo4, S. Parta6, T. Dutta4, P. Swain4, S. Gupta4, H. Nayak4, S. Mishra4, and D. K. Parida4; 1All India Institute of Medical Sciences, Bhubaneswar, Bhubaneswar, India, 2Tata Memorial Hospital, Mumbai, India, 3Tata Medical Centre, Kolkata, India, 4AIIMS Bhubaneswar, Bhubaneswar, India, 5Utkal Hospital, Bhubaneswar, India, 6IMS SUM, Bhubaneswar, India
Purpose/Objective(s):
Adaptation of Total Neoadjuvant Therapy in the management of Carcinoma Rectum is still variable in Indian patients and data regarding the safety and efficacy for the same is lacking. Hence this RCT was initiated to compare the rate of pathological outcomes , survival benefits and toxicity in patients of locally advanced rectal adenocarcinoma receiving short course radiotherapy (5 x 5 Gy), followed by chemotherapy and surgery vs Long Course Chemo Radiotherapy followed by Surgery.Materials/Methods:
The study is a single institutional Phase III Randomized Controlled Study done in a tertiary care hospital. Patients with cT3/4 or N + rectal adenocarcinoma with ECOG 0-1 were randomized between LCRT and SCRT TNT arms. LCRT arm: 45–50.4 Gy in 25–28 fractions with concurrent capecitabine, followed by Total Mesorectal Excision (TME). SCRT TNT arm: 25 Gy/5 fractions (1 week) followed by six cycles of CAPOX (oxaliplatin 130 mg/m² D1 + capecitabine 1000 mg/m² BID D1–14 q21 days) before TME. Pathologic response, resection quality, toxicity, and survival outcomes were analyzed.Results:
A total of 104 patients were enrolled (LCRT = 51; SCRT TNT = 53). Median age was 53 years (LCRT) and 49 years (SCRT TNT); 64% were male and > 80% had Stage III disease. Objective response rate was 47% (LCRT) vs 51% (SCRT TNT). Surgery was performed in 76.4% vs 85% of patients, with negative circumferential resection margins in 90% vs 88%, respectively. Pathologic complete response (pCR) was 9.8% in LCRT and 18.9% in SCRT TNT. At median follow-up of 24 months (range 6–35), median overall survival was 23 months (SCRT TNT) vs 15.5 months (LCRT; p = 0.14), and median PFS was 18 vs 14 months (p = 0.19). Stage IIIC and mucinous/signet-ring histology correlated with early recurrence, whereas pCR conferred > 90% 2-year survival. Acute GI and hematologic toxicities were lower with SCRT TNT (p ˜ 0.09).Conclusion:
TNT-based SCRT and LCRT achieved comparable oncologic outcomes in Stage II–III LARC. Although survival differences were not statistically significant, SCRT TNT demonstrated a clinically meaningful OS/PFS gain (~8 months), higher pCR rates, similar local control (< 10% recurrence), and lower treatment-related toxicity. SCRT TNT emerges as a time-efficient, safe, and effective alternative to LCRT for appropriately selected rectal cancer patients in resource-restricted settings.