Electron microscopic study of papillary serous tumors of the ovary

Abstract

Electron microscopic evaluation was performed in a series of papillary serous tumors of the ovary, including 4 cystadenomas, 2 cystadenocarcinomas, and 2 tumors with questionable histologic evidence of malignancy. Marked nuclear irregularity was found in the cells of those tumors which were malignant by histologic criteria. Nuclei of cells from benign tumors had a regular shape and outline, with only shallow indentations. In the cases with borderline malignant changes, an intermediate degree of nuclear irregularity was present. Many of the cells showed a marked degree of nuclear infolding, comparable to that of the frankly malignant tumors. A decreased amount of cell membrane interdigitation was observed in the malignant tumors as compared to the benign. The borderline group was intermediate in this respect. Cilia were present in the benign and borderline malignant tumors but were not seen in the frankly malignant tumors. The findings indicate that electron microscopic analysis may be a useful adjunct in the evaluation of papillary cystic tumors of the ovary.

The diagnostic utility of immunohistochemistry and electron microscopy in distinguishing between peritoneal mesotheliomas and serous carcinomas: a comparative study

“…Multiciliated cells, such as those shown in Figure 10a and b, have previously been reported in serous carcinomas and are more often found in low-grade serous carcinomas and serous tumors of borderline malignancy originating in the ovary and peritoneum. 23,24,[69][70][71][72] Neither in the present study nor in previous investigations have these cells been found in mesotheliomas. Cells presenting a solitary cilium or a few cilia have frequently been found in serous carcinomas, including those of high-grade malignancy; however, their occurrence in mesotheliomas is exceedingly rare.…”

“…Similar to previous ultrastructural studies, large collections of intermediate filaments arranged in tonofibrillar bundles and intracytoplasmic lumens covered by microvilli were common findings in mesotheliomas, [65][66][67] but not in serous carcinomas. [68][69][70] No intracytoplasmic lumens were identified in any of the serous carcinomas investigated, and only rare small bundles of intermediate filaments were found in a few cases. Another finding that was helpful in distinguishing serous carcinomas from mesotheliomas was the presence of multiciliated cells in serous carcinomas, but not in mesotheliomas.…”