PALLIATIVE ENDOBRONCHIAL BRACHYTHERAPY FOR CENTRAL LUNG-TUMORS - A PROSPECTIVE, RANDOMIZED COMPARISON OF 2 FRACTIONATION SCHEDULES

Aim of the study: Remote high dose rate brachytherapy is an effective local treatment modality for central lung tumors and has the potential to improve survival time. Optimal dose and fractionation schemes have not been identified yet. We conducted a prospective randomized study to compare two treatment schedules in terms of survival time, local tu mor control, and possible complications.Design: Group 1 received 4 bra chytherapies with a dose of 3.8 Gy (at a 10-mm depth) on a weekly basi s, and group 2 received 2 treatments with 7.2 Gy (at a 10-mm depth) at a 3-week interval. At a depth of 5 mm, the calculated doses would be 8 and 15 Gy. This study is still ongoing. Here we report interim resul ts. Patients: Ninety-three patients with advanced cancer were included in the study; 44 were in group 1 and 49, in group 8,]Both groups were comparable regarding age, sex, tumor stage, Karnofsky performance sta tus, and histologic findings. Interventions: A mean total irradiation dose of 13.4 +/- 5.2 Gy for group 1 and 13.7 +/- 4.4 for group 2 were applied (calculated at 10 mm from the source axis, equivalent to 27.9 Gy in group 1 and 28.5 Gy in group 2 at a 5-mm depth).Results: The 1-y ear survival rate was 11.4% in group 1 and 20.4% in group 2. No signif icant difference in survival time was found, but mean survival was lon ger in group 2 (49 weeks) than in group 1(26 weeks). Local control aft er 3 months was comparable in both groups. Fatal hemoptysis occurred a t a similar rate in group 1 (22.2%) and in group 2 (21.1%). Conclusion : High-dose rate brachytherapy with 2 x 7.2 Gy with a 3-week interval is equivalent to a 4 x 3.8-Gy regimen on a weekly basis. The shorter t reatment schedule is more convenient for patients, does not cause more side effects, and provides an equal local tumor control.