Objectives: The management of inoperable oral cavity squamous cell carcinoma (OCSCC) is onerous. We aimed to retrospectively analyse the outcome of our cohort of inoperable OC-SCC treated with definitive concurrent chemoradiotherapy (CTRT) with or without induction chemotherapy (IC).

Methods: Data of 100 patients (January 2017 to May 2022) of histopathologically proven inoperable OC-SCC treated with definitive CTRT with weekly cisplatin 40 mg/m2 were retrieved from our departmental archives. Radiotherapy (RT) was delivered with three-dimensional conformal plan (66–70 Gy). Toxicities were evaluated using acute morbidity scoring criteria of Radiation Therapy Oncology Group. The response was evaluated as per WHO criteria. Progression free survival (PFS) was calculated from the date of the start of treatment (IC/CTRT) using Kaplan Meier method.

Results: Median age was 45 years (range 30–80 years). The primary site was oral tongue (59%), retro-molar trigon (15%), buccal mucosa (15%) and others (11%). The stage was III: IVA: IVB in 16:70:14 patients respectively. 72% patients received IC (platinum ± 5 FU ± taxane). Grade 3 skin toxicity, oral mucositis and dysphagia was noted in 13 (13%), 19 (19%) and 13 (13%) patients respectively. The median follow-up duration was 30.5 months (range 6–62 months). Complete response (CR), partial response, progressive disease and death at the time of the last follow-up were 49%, 25%, 15% and 11% respectively. 2-year PFS rate was 49.5%. Stage III patients had a higher CR rate (81.2% versus 42.8%; p = 0.0051) and higher 2-year PFS (81.2% versus 46.4%; p = 0.0056) in comparison to stage IV patients. 

Conclusion: Inoperable patients of OC-SCC treated with definitive CTRT with or without IC yielded CR in approximately half of patients with acceptable toxicity profiles.