Dose-escalated external beam radiotherapy during hormono-radiotherapy for prostate cancer

Introduction. The introduction of modern technologies of conformal external beam radiotherapy (EBRT) into clinical practice for the treatment of prostate cancer requires proper quality assurance measures as well as a careful analysis of both the efficacy and toxicity data of treatments. The purpose of this study was to inves- tigate tolerance and the immediate efficacy of conformal dose-escalated EBRT during hormono-radiotherapy for prostate cancer. material and methods. The study involved 156 prostate cancer patients treated with EBRT. Among them, 30 patients received a total dose of 70 Gy, and in 126 patients the total dose was esca- lated to 72-76 Gy (median total dose - 74.0 Gy). Fifty-nine patients received intensity modulated radiation therapy. Results. The prescribed course of treatment was completed in all the patients with prostate cancer. Acute radiation-induced bladder reactions (RTOG) were observed in 50 (32.1 %) patients, of whom 48 (30.8 %) experienced grade I reactions, and 2 (1.3 %) experienced grade II reactions. Eighteen (11.5 %) patients had radiation-induced rectum reactions, not above grade I. The development of grade II dysuric phenomena necessitated treatment interruption only in two patients. Of 9 (5.8 %) patients who had late bladder complica- tions (RTOG/EORTC), 8 (5.1 %) patients developed grade I complications, and one (0.6 %) patient developed grade II complications. Of 11 (7.1 %) patients who had rectum complications, 8 (5.1 %) patients developed grade I complications, and 3 (1.9 %) patients developed grade II complications. No patients experienced the increase in toxicity of treatment during dose escalation up to a total dose exceeding 70 Gy. During the follow-up period, only one patient developed recurrent disease. Conclusion. The results of our study suggest acceptable levels of toxicity following a continuous course of dose-escalated EBRT given in conjunction with hormono-radiotherapy to prostate cancer patients. Further studies are needed to investigate the impact of dose escalation on long-term outcomes as well as the rate and grade of late complications.