Article

Concomitant boost radiotherapy for muscle invasive bladder cancer.

Department of Radiotherapy, Academic Medical Center, University of Amsterdam, P.O. Box 22700, 1100 DE, Amsterdam, The Netherlands.
Radiotherapy and Oncology (Impact Factor: 4.52). 08/2003; 68(1):75-80. DOI: 10.1016/S0167-8140(03)00019-7
Source: PubMed

ABSTRACT To evaluate the feasibility and efficacy of a concomitant partial bladder boost schedule in radiotherapy for invasive bladder cancer, coupling a limited boost volume with shortening of the overall treatment time.
Between 1994 and 1999, 50 patients with a T2-T4 N0M0 transitional cell carcinoma of the bladder received radiotherapy delivered in a short overall treatment time with a concomitant boost technique. With this technique a dose of 40 Gy in 2-Gy fractions was administered to the small pelvis with a concomitant boost limited to the bladder tumor area plus margin of 15 Gy in fractions of 0.75 Gy. The total tumor dose was 55 Gy in 20 fractions in 4 weeks. Toxicity was scored according to EORTC/RTOG toxicity criteria.
The feasibility of the treatment was good. Severe acute toxicity >/=G3 was observed in seven patients (14%). Severe late toxicity >/=G3 was observed in six patients (13%). Thirty-seven patients (74%) showed a complete and five (10 %) a partial remission after treatment. The actuarial 3-year freedom of local progression was 55%.
In external radiotherapy for muscle invasive bladder cancer a concomitant boost technique coupling a partial bladder boost with shortening of the overall treatment time provides a high probability of local control with acceptable toxicity.

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