Cytologic findings in primary malignant carcinoid tumor of the cervix. Including immunohistochemistry and electron microscopy performed on cervical smears.

The cytologic findings in a primary malignant carcinoid tumor of the cervix are presented. In addition to the presence in the smears of cells suggestive of squamous carcinoma and adenocarcinoma, which led to an initial diagnosis of adenosquamous carcinoma, there were multinucleated giant cells with prominent, reddish nucleoli, finely granular chromatin and grayish-blue to eosinophilic cytoplasm, as well as smaller pleomorphic cells, against a tumor-diathesis type of background. Immunocytochemistry performed on the cervical smears showed the presence of serotonin, and ultrastructural analysis revealed abundant intracytoplasmic, membrane-bound granules in malignant cells, thus confirming the diagnosis of a carcinoid tumor.