[The degree of differentiation and the clinical course of ovarian cancer]

Clinical course versus morphological data on the level of tumor cell differentiation was studied in 323 cases of cancer of the ovaries. Level of cell differentiation proved to be of prognostic value, since it appeared to influence prognosis and clinical course greatly. Metastasis developed in 58.2 +/- 4.5% of patients suffering well-differentiated ovarian cancer. In cases of moderately- and poorly-differentiated cancer, it was 76.1 +/- 5.1 and 90.8 +/- 2.5%, respectively. The high level of tumor cell differentiation was registered in 41.8 +/- 4.5% of patients with cancer at early stages (I and II), while the low--level--in 9.2 +/- 2.5% only. This was matched by the predominance of poorly--differentiated tumors over those with high level of cell differentiation (90.8 +/- 2.5 and 58.2 +/- 4.5%, respectively). The five-year survival rate in patients with poorly--differentiated tumors was 8.3 +/- 2.5%, i. e. 7.8 times lower than in cases of tumors with high level of cell differentiation.