Detection of p53 antigen expression in cytologic preparations of ovarian carcinomas

We explored the value of p53 immunostaining in detection of malignant cells in cytologic analyses in ovarian cancer patients. Ninety-six percent of 23 tumor touch preparations had nuclear staining with PAb240: 44% had nuclear only, 26% had both nuclear and cytoplasmic staining, and 26% had cytoplasmic staining alone. Eight of 20 cytospins of peritoneal washings from ovarian cancer patients were PAb240 positive, 6 had cytoplasmic, and two had nuclear staining. Cytospins of fluid from 3/15 patients with no malignancy revealed cytoplasmic staining of mesothelial cells. The lack of concordance between staining of primary tumors and cytospins of peritoneal washings and the apparent reactivity in some benign samples may limit the utility of immunohistochemical detection of malignant cells in the peritoneal fluid of ovarian cancer patients.