A Comparative Study to Evaluate Response and Toxicities of Conventional versus Hypofractionated Sequential Chemoradiotherapy in Patients with Inoperable Locally Advanced Non-Small Cell Lung Cancer

Background: Current standard treatment approach for inoperable locally advanced non-small cell lung cancer (NSCLC) is sequential or concurrent conventional chemoradiotherapy. Local tumor control is necessary for the cure of lung cancer. As there is a chance of compromised local control due to accelerated repopulation of tumor cells during conventional radiotherapy, hypofractionated radiotherapy is a strategy to minimize accelerated repopulation that might improve local control. Objectives: To evaluate and compare the response and toxicities of conventional and hypofractionated sequential chemoradiotherapy in inoperable locally advanced stage III NSCLC. Methods: A Quasi-Experimental study was carried out from January 2021 to December 2021 at the Department of Radiation Oncology, National Institute of Cancer Research & Hospital (NICRH), Dhaka, Bangladesh. Total 66 patients with histologically proven, inoperable locally advanced stage III NSCLC were divided into Arm A and B, 33 patients in each arm. All patients were treated with 4 cycles of chemotherapy (Inj. Paclitaxel and Inj. Carboplatin) on Day 1. After completion of chemotherapy, patients of Arm A were treated with conventional fractionated radiotherapy, 60 Gy in 30 fractions, 2 Gy per fraction, 5 days in a week over 6 weeks and patients of Arm B were treated with hypofractionated radiotherapy, 55 Gy in 20 fractions, 2.75 Gy per fraction, 5 days in a week over 4 weeks. Then regular assessments of all study patients were done to evaluate treatment responses and toxicities. Data were analyzed and compared by statistical tests. Results: The mean age was 56 ± 5.8 years in Arm-A and 56.61 ± 5.8 years in Arm-B. The overall response rate in hypofractionated arm was 78.8% and in conventional arm was 69.7% (p > 0.05). Although toxicities (grade 1 and 2) were slightly higher in Arm B (p > 0.05). At 6 months, no significant difference in terms of treatment responses and toxicities were found between two groups (p > 0.05). Conclusion: Hypofractionated sequential chemoradiotherapy is equally effective as conventional fractionated sequential chemoradiotherapy in locally advanced, inoperable NSCLC in terms of treatment response and toxicities.