Multidisciplinary treatment of primary XXXX of bone. A 6-year experience of a European Cooperative Trial.

@entity1 @entity2828 @entity5 @entity3
The German Society of Pediatric Oncology in 1981 initiated the Cooperative @entity2828 Study (CESS 81) using a four-drug combination of chemotherapy prior to definitive local control with surgery and/or radiation. From January 1, 1981 until February 28, 1985, 93 @entity1 were registered at the trial office from 54 participating institutions in West Germany, Austria, Switzerland, and the Netherlands. On February 1, 1987, 54 of 93 @entity1 were disease-free. Using the Kaplan-Meier life table analysis, the estimated disease-free survival (DFS) rate was 60% at 36 months and 55% at 69 months. The median period of observation was 29 months, ranging from 22 months to 69 months. Twenty-one of 93 @entity1 (23%) had local failure, 18 of 93 @entity1 (19%) developed systemic @entity3 . The local failure rate was particularly high in @entity1 treated with radiation and was reduced when radiation planning was centralized within the study based upon the extent of disease at diagnosis. Cox regression analysis of prognostic factors showed that @entity5 volume was a significant factor influencing prognosis. The estimated 3-year DFS rate was 80% for @entity1 with small @entity5 (volume less than 100 ml) compared to 31% for @entity1 with large @entity5 (volume greater than or equal to 100 ml). In @entity1 who had surgery for local control, the histologic response to chemotherapy was analyzed on the surgical specimen and had a strong influence on survival: 79% DFS at 3 years for @entity1 with less than 10% viable @entity5 (good responders) compared to 31% DFS for @entity1 with more than 10% viable @entity5 (poor responders). @entity5 load and responsiveness to chemotherapy are the two major factors influencing prognosis in @entity1 with primary @entity2828 of bone.
