Results of curative pion therapy at SIN.

The experiences of the treatment of bladder carcinoma indicated the direction in which the dose optimization program of intraabdominal tumours can be carried out. Small intraabdominal target volumes seem to tolerate doses from 31 to 33 Gy applied in 20 fractions. The best results with local tumour control and low complication rates have so far been reached in carcinoma of the cervix. It has not so far been organizationally possible at SIN to treat with pions on more than four days per week. This restricts changes to the fractionation scheme in the treatment of highly malignant gliomas. An improvement of results could be possible on the basis of experience to date. The significance of a postbiopsy preoperative radiotherapy, of the increase of target volume and the increase of the total dose will be tested in a study by the SAKK (Swiss Group for Clinical Cancer Research).