[Teletherapy versus teletherapy and "boost" brachytherapy in the treatment of base of tongue tumors: 5-year results].

Aim: To study the importance of high-dose-rate (HDR) boost brachytherapy (BT) after percutaneous irradiation of base of tongue tumors. Methods: Between 1992 and 2000 seventy patients with biopsy proven carcinoma of the base of tongue were treated with primary radiation therapy. Fourty patients received a mean dose of 61 Gy (range, 50-72 Gy) external beam irradiation, and afterwards 30 patients were treated with a mean dose of 18 Gy (range, 12-30 Gy) boost HDR BT. Prognostic factors were analyzed in uni- and multivariate model. Results: At a median follow-up of 56 (16-108) months, boost BT increased the incidence of local tumor control (LTC) from 38% to 67% (p=0.0145). The 5-year probability of LTC was 60% vs. 36% (p=0.0188), the locoregional tumor control 52% vs. 34% (p=0.0753) and the overall survival (OS) 46% vs. 26% (p=0.0545), respectively, in favor of the boost group. Serious, grade 4 radiation toxicity occurred in 5% (2/40) and 13% (4/30) without or with boost treatment, respectively (p=0.2110). In multivariate analyses for LTC, tumor size (p=0.0042) and boost (p=0.0444), and for OS tumor size (p=0.0047) and nodal status (p=0.0163) had a significant effect. Conclusion: Boost BT after teletherapy improves LTC significantly without considerable increase in the risk of side-effects. Takacsi Nagy Z, Oberna F, Somogyi A. Polgar C, Major T, Polus K, Fodor J, Nemeth G. Teletherapy versus teletherapy and „boost” brachytherapy in the treatment of base of tongue tumors: 5-year results. Hungarian Oncology 48:297–301, 2004