Objective: To correlate Pap smear findings with the histology of endometrial carcinoma and stage of the disease.
Study design: Between 1995 and 1998, 76 women with endometrial carcinoma, having had Pap smears done within two to three months of hysterectomy at Memorial Sloan-Kettering Cancer Center, formed the basis for this study. All Pap smears and histologic sections were reviewed.
Results: Thirty-four patients had normal Pap smears (45%), and 42 had abnormal ones (55%). The mean age of the two groups was 65.1 and 65.2 years, respectively. Histologic subtypes included 44 International Federation of Gynecology and Obstetrics (FIGO) grade 1 endometrioid adenocarcinoma (low grade) and 32 high grade carcinomas, including 19 FIGO grade 2 or 3 endometrioid adenocarcinomas, 5 papillary serous carcinomas (PSC), 2 clear cell carcinomas (CC), 1 adenosquamous carcinoma, 3 endometrioid adenocarcinomas mixed with PSC and 2 endometrioid adenocarcinomas mixed with CC. The proportions of patients with low and high grade tumors with abnormal Pap smears were 43% (19/44) and 72% (23/32), respectively (P=.01). The proportions of patients with abnormal Pap smears and no myometrial invasion, invasion of <50% and >50% myometrial thickness were 40% (8/20), 62% (26/42) and 57% (8/14), respectively (P =.27). Vascular invasion was identified in 56% (9/16) of patients with abnormal Pap smears and in 55% (33/60) of patients with normal ones (P = .93). The proportions of patients having abnormal Pap smears with stage I and stages II, III or IV disease were 48% (30/62) and 86% (12/14), respectively (P =.01).
Conclusion: Although the Pap smear is not a sensitive screening test for endometrial cancer and a negative Pap smear does not rule it out, this study revealed that abnormal Pap smears are significantly associated with high grade of tumor and stage II-IV endometrial carcinoma. However, they are not associated with patient age, depth of myometrial invasion or vascular invasion.