A clinicopathologic study of 66 patients with 33 heterologous tumors and 33 carcinosarcomas followed for 5 years after treatment is presented. The significantly better prognosis of the carcinosarcoma patients supports the opinion that subclassification of these types of neoplasms has practical value. The survival rate for both groups of tumors is influenced by the degree of myometrial invasion and the patient's age; these 2 factors bear an inverse relationship to survival time. A second malignant tumor was diagnosed in 7.5% of the patients. Prior irradiation was not an important factor. In this material, the 5-year overall survival rate was 30% for mixed mesodermal (heterologous) tumors and 43.7% for the carcinosarcomas. HE PRESENT REPORT CONCERNS 66 PA-T tients followed for 5 years after treatment. With the exception of one point, our results correspond with those of Norris et al.l1,12 The divergence concerns the prognostic significance of a rhabdomyosarcomatous component.
We have been able to compile the following series of tumors from a large number of hospitals and laboratories in the Nether-land&'*: Group I(a) 29 mixed' heterologous tumors (preferably termed heterotopic, according to Nichol~on),~ (b) 4 rhabd'omyosarcomas or pure heterologous tumors; and Group 11, 33 carcinosarcomas or mixed homologous tumors.
This does not include endometrial stroma sarcomas, botryoid sarcomas, collision tumors, undifferentiated sarcomas, and leiomyosarcomas. Group I is subdivided because the composition of the material of other authors is not clear from the literature.
CLINICAL ASPECTS
Frequency: With respect to the primary uterine sarcomas, the frequency varied widely. The figures in the literature vary from l l % 4 to 53%,19 with a mean of 29%. In the material of 2 Dutch laboratories, we found 540/, (H. Joannes de Deo Hospital, From p/a Vrouwenkliniek, Academisch Ziekenhuis,