Preliminary results of a randomized study of adjuvant radiation therapy in resectable adult retroperitoneal soft tissue XXXX .

@entity1 @entity1161 @entity1897 @entity242
Between January 1980 and September 1985, 35 adult @entity1 with resectable retroperitoneal soft tissue @entity242 were entered on a randomized trial comparing two forms of adjuvant radiation therapy. Fifteen @entity1 received the experimental therapy consisting of intraoperative radiotherapy (IORT) to 20 Gy using high-energy electrons followed by low-dose (35 to 40 Gy) postoperative external beam irradiation. Twenty @entity1 received standard therapy consisting of high-dose (50 to 55 Gy) postoperative external beam irradiation. With a minimum follow-up of 15 months, there is no significant difference in the actuarial disease-free survival (DFS) and overall survival (OS) comparing the two groups (median DFS, 34 months; median OS, 38 months). At 5 years follow-up, approximately 40% of @entity1 are alive and 20% of @entity1 remain disease-free. Although there is a trend towards an improvement in in-field local control in the experimental arm, the predominant pattern of failure in both groups was locoregional within the retroperitoneum and/or peritoneal cavity. Acute and late @entity1161 were significantly reduced in the experimental group. However, four experimental @entity1 developed late (greater than 6 months following treatment) @entity1897 believed related to the use of IORT; all four recovered. We conclude that there is no difference in the therapeutic effectiveness of the combination of IORT and low-dose external beam radiation compared with conventional high-dose radiation as adjuvant treatment in @entity242 , although the former appears to be less toxic. Newer combined modality treatment strategies are discussed to improve the prognosis in these @entity1 .
