Vol. 5, Issue 1, Part A (2025)

Background: Locally advanced carcinoma of the base of the tongue (BOT) is a rare and aggressive cancer, requiring precise therapeutic approaches such as intensity-modulated radiotherapy (IMRT) combined with concurrent chemotherapy. 
Objective: To assess the efficacy, toxicity, and outcomes of IMRT with concurrent chemotherapy in treating locally advanced BOT carcinoma at Cancer Center, Combined Military Hospital (CMH), Dhaka. 
Methods: A retrospective observational study was conducted at CMH Dhaka from 2018 to 2023. Forty patients with locally advanced BOT (T3-4a, any N) were purposively selected. Efficacy was evaluated based on clinical symptoms, radiological changes, histopathology, and survival data. Toxicity was assessed for mucositis, dermatitis, xerostomia, and other related side effects. The data were analyzed using mean, standard deviation (SD), and p-value to assess significance. 
Results: Among the 40 patients, 85% exhibited clinical improvement, with a significant reduction in tumor size. Radiological evaluations revealed a 70% complete response (CR) and a 20% partial response (PR). The mean tumor size reduction was 35%, with a standard deviation of 6.5%. For clinical symptoms, 78% of patients reported significant alleviation of pain (p-value = 0.01), while 72% experienced a marked improvement in swallowing function (p-value = 0.03). Toxicity was observed in 75% of patients for mucositis, 45% for dermatitis, and 65% for xerostomia. The mean overall survival (OS) rate at 1 year was 78%, with a standard deviation of 5%. The p-value for survival was 0.02, indicating a statistically significant improvement in survival compared to historical data. Multivariate analysis showed a correlation between higher chemotherapy dosage and better survival outcomes (p-value = 0.04). A significant positive correlation was found between tumor response (CR/PR) and overall survival (p-value = 0.01). 
Conclusion: IMRT combined with concurrent chemotherapy offers significant tumor control and improved survival rates for locally advanced BOT carcinoma, although treatment-related toxicity remains a concern.