Combined morphologic and cytochemical grading of serous ovarian tumors.

The potentiality of DNA analysis to complement morphologic evaluation in classifying serous ovarian tumors as adenoma, borderline malignancy, or invasive adenocarcinoma was investigated in a series of 54 tumors. The DNA analyses were performed on histologic tumor sections. The primary diagnoses were borderline tumor in 24 cases and invasive adenocarcinoma in 30 (World Health Organization classification). When the specimens were reviewed, 17 of the 54 tumors were reclassified, after which the series consisted of 9 adenomas, 24 borderline tumors, and 21 invasive adenocarcinomas. Rising histologic malignancy grade was associated with increasing numbers of cells showing high DNA content. The DNA levels in the adenomas thus were within the diploid range of a normal cell population. They were somewhat higher in the borderline tumors and were highest in the invasive adenocarcinomas. Though no clear-cut intergroup demarcation was discernible, there was a subgroup of adenocarcinomas with greatly elevated DNA levels, indicating high biologic malignancy. The observations suggested that DNA analyses can complement histologic malignancy grading and can be useful for the recognition or highly malignant tumors among invasive adenocarcinomas.