Comparative Efficacy and Toxicity of Weekly Carboplatin Versus Cisplatin in Concurrent Chemoradiotherapy for Locally Advanced Head and Neck Squamous Cell Carcinoma: A Quasi-experimental Study From Bangladesh

Background Cisplatin-based concurrent chemoradiotherapy (CCRT) is the standard care for locally advanced squamous cell carcinoma of the head and neck (LA-SCCHN). However, its toxicity limits use, especially in resource-limited settings. Carboplatin, with less toxicity, is a potential alternative, yet comparative South Asian evidence is scarce. This study compared the efficacy and toxicity of weekly carboplatin versus cisplatin, concurrently with radiotherapy in patients with LA-SCCHN. Methodology This quasi-experimental study was conducted at a tertiary care hospital in Bangladesh. A total of 90 patients with histologically confirmed LA-SCCHN were non-randomly allocated to receive either weekly cisplatin (40 mg/m²) or weekly carboplatin (area under the curve (AUC)-2), concurrently with external beam radiotherapy (66 Gray over 6.5 weeks). Treatment response was evaluated using Response Evaluation Criteria in Solid Tumors version 1.1, and toxicity was graded per Common Terminology Criteria for Adverse Events version 3.0. Statistical analysis was performed using SPSS version 25 (IBM Corp., Armonk, NY, USA), with a p-value <0.05 considered significant. Results Both cisplatin and carboplatin demonstrated comparable complete response rates of 17 (37.8%) versus 18 (40.0%) at six weeks, 18 (40.0%) versus 20 (44.4%) at 12 weeks, and 19 (42.2%) versus 22 (48.9%) at 24 weeks, with statistically insignificant differences. Cisplatin was associated with higher rates of mucocutaneous and gastrointestinal toxicities, while carboplatin was linked to increased hematologic toxicity, particularly thrombocytopenia (p = 0.040). Late toxicities were similar across groups. Conclusions Weekly carboplatin demonstrated comparable efficacy to weekly cisplatin, with radiotherapy for LA-SCCHN, with a distinct toxicity profile. Carboplatin may be a clinically viable alternative for patients unsuitable for cisplatin, particularly in settings with limited supportive care.