Abstract 937P
Background
This single Institute audit analysed curative intent treatment for oral cavity squamous cell carcinomas (OCC) receiving adjuvant radio(chemo)therapy with intensity modulated radiotherapy (IMRT). Outcomes, failure patterns and acute and late toxicity profiles were documented.
Methods
Three hundred and fifteen OCC patients receiving curative intent surgery and adjuvant IMRT were analysed over thirty two months. Re-irradiation, incomplete IMRT and lost to follow up were excluded. Outcomes were of local control (LC), disease free survival (DFS) and overall survival (OS). Failure patterns were analysed by deformable image registration (Type A-E). The acute and late toxicities as well as quality of life scoring till last follow up was documented. The statistical analysis was performed using Kaplan Meir method and logistic regression.
Results
The median age was 60 years with male preponderance (77.4%). 75% patients were locally advanced stage (any TN+ or T3-4anyN or both) and 80% received concurrent chemotherapy as per protocol with cisplatin being commonest. 15% patients also received neo-adjuvant chemotherapy. Buccal mucosa was the commonest subsite. The median IMRT dose was 60 Gy and target volumes were as per standard International guidelines. With a median follow up of 24 months, median OS was 18 months and median DFS was 15 months. The 2 years LC, DFS and OS among early and advanced stages were 82%, 78%, 75% and 65%, 63%, 60% respectively. In multivariate analysis stage, nodal burden, tobacco, tongue primary and oral submucous fibrosis were negative for survival and in early stage with perineural invasion. Type A failure (local) remained major (85%) and only 5% were type B. Type E failure was 8% and distant metastasis was 5%. Grade 3 acute toxicity for mucositis and dysphagia were 20% and 30% respectively. Late toxicity of xerostomia and dysphagia were 10-15% and less than 5% were osteoradionecrosis, grade 3 trismus and oro-cutaneous fistulas.
Conclusions
The single centre OCC data re-validates need of adjuvant treatment and adds to evidence of IMRT. Since local failure remains a major concern future studies with dose escalation, radiosensitization and biological agents should be considered.
Clinical trial identification
Editorial acknowledgement
Legal entity responsible for the study
The authors.
Funding
Has not received any funding.
Disclosure
All authors have declared no conflicts of interest.