Primary serous peritoneal carcinoma presenting first on a routine papanicolaou smear: a case report.

ABSTRACT

BACKGROUND: Primary peritoneal carcinoma (PPC) is a relatively uncommon malignancy, and its presentation is similar to that of advanced ovarian serous carcinoma. There have been afew case reports in which the malignant cells from PPC were discovered from routine Papanicolaou (Pap) smears. CASE In 2006 a 49-year-old, asymptomatic female participated in the Hospital Health Fair. High grade adenocarcinoma was found by Pap smear. After negative cervical and endometrial curetting and loop electrosurgical excision procedure cone, laparoscopy revealed widespread peritoneal carcinomatosis. The subsequent surgical specimens showed primary peritoneal serous carcinoma. CONCLUSION: Although the Pap smear was originally designed to detect premalignant cervical lesions and cancer, it became apparent that malignant cells from extrauterine primaries might appear in the smears. This case illustrated the value of the Pap smear in discovering unsuspected extrauterine malignancies, including PPC. Review of 9 cases showed tumor cells in the fallopian tube lumen in 4 out of 9 cases, indicating the likely route of efflux of tumor cells to appear in the Pap smear. The new concept of serous tubal intraepithelial carcinoma as the origin of PPC suggests another source of tumor cells in Pap smears.