Prognostic value of peritoneal washings in patients with malignant mixed müllerian tumors of the uterus.

Peritoneal washings from 36 women with all pathologic stages of mixed müllerian tumors of the uterus (27 homologous stroma, nine heterologous stroma) were reviewed in a blinded retrospective fashion for the presence and type of malignant cells collected. Malignant tumor cells were demonstrated in the washings of 16 patients; 13 contained adenocarcinoma only, two contained adenocarcinoma and sarcoma, and one contained sarcoma cells only. Cox's logistic regression analysis showed that cytologic examination of peritoneal washings when combined with pathologic staging provides a statistically significant discriminant of disease-free survival. Patients with a favorable prognosis (pathologic Stage I and peritoneal washings free of malignancy) had sevenfold increased disease-free survival compared with survival of the patients with an unfavorable prognosis (pathologic Stages II, III, or IV or malignant cells present in peritoneal washings). Three of the 18 patients with pathologic Stage I disease manifested malignant tumor cells in the peritoneal washings and all three patients died of disease in less than 1 year. The presence of malignant cells in peritoneal washings in patients with mixed müllerian tumor apparently limited to the uterus suggests a clinical course that is similar to that of those with more advanced disease.