ESTRO 2023 - Abstract Book

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ESTRO 2023

one fraction per day, 5 days a week with or without weekly concurrent cisplatin 40mg/m2. Statistical analysis was done using SPSS (version 29.0; IBM). Kaplan-Meier method was used for all survival analysis. Log-rank test was used for univariate analysis. Variables which came significant in univariate analysis were analyzed further by multivariate analysis using cox regression test. Results Median age of presentation was 48.72 years (IQR:21-82 years) with a male to female ratio of 2.2:1. Median follow up was 25.48 months. The eighth edition American Joint Committee on Cancer stage distributions in this study were I (14.1%), II (35.4%), III (23.6%), and IV (25.9%). 25 patients received concurrent cisplatin.2-year local control(LC) rate, regional control(RC)rate and locoregional control(LRC) rate were 84.3%, 89.8% and 70.9% respectively. There were 4 locoregional failures. Of the 20 local failures, 15 recurred in the post operative residual tongue. 13 patients had nodal recurrence of which 1 patient had contralateral neck failure. Of all the factors, close margin(<=5 mm) on histopathological examination was statistically significant(p=0.05) for local control(LC) rate, while TNM Stage III/IV (p=0.01) and PNI(p=0.02) statistically influenced regional control(RC) rate. 2-year overall survival(OS) for the entire study was 82.7%. Pathologically pN+ (p=0.02), pN2/N3(p=0.007), TNM Stage IV(p=0.009), LVI(p=0.05) were statistically significant for OS on multivariate analysis. 2-year disease free survival(DFS) was 79% and TNM Stage IV statistically influenced(p=0.02) DFS.

Conclusion IMRT provides excellent control rates in oral tongue cancer. Close margin resulted in higher local failures, hence dose escalation may be considered. Higher nodal stage and nodal burden significantly reduce OS.

PO-1188 older age: a factor of worse prognosis and tolerance in nasopharyngeal cancer

M.S. Amraoui 1 , N. Sellal 1 , W. Merssetti 1 , M. El Hfid 1

1 University Hospital Mohamed 6, Radiotherapy, Tangier, Morocco

Purpose or Objective