TUBAL METAPLASIA OF THE UTERINE CERVIX - A PREVALENCE STUDY IN PATIENTS WITH GYNECOLOGIC PATHOLOGICAL FINDINGS

Tubal metaplasia (TM) of endocervical epithelium may be confused with endocervical dysplasia or adenocarcinoma in histologic or cytologic sp ecimens. However, the potential magnitude of this problem is unknown, because the prevalence of endocervical TM in routine surgical patholog y material is undefined. To determine the prevalence, distribution, an d associated features of endocervical TM, we retrospectively reviewed a consecutive series of cone biopsy specimens (n = 82) and hysterectom y specimens in which the entire cervix had been sectioned (n = 26), ob tained over 28-months. Tubal metaplasia was defined as epithelium cont aining all three cell types (ciliated, secretory, and intercalary) fou nd in the normal fallopian tube. The mean patient age was 41 years (ra nge, 21-79). Endocervical TM was present in 33 of 108 patients (31%) a nd was evenly distributed among all age groups. Its prevalence was rel ated to the number of sections examined (23% of cases with less-than-o r-equal-to 12 blocks of the cervix; 52% of cases with > 12 blocks; p < 0.01) and was greater in hysterectomy than in cone specimens (62 vs. 21%, p < 0.001). Although most frequent in the upper endocervix and in deep portions of glands, TM involved the surface in 36%, the superfic ial parts of glands in 64%, and the lower endocervix in 30% of positiv e cases. There was no association with phase of the menstrual cycle, i nflammatory changes, or low-grade cervical intraepithelial neoplasia ( CIN), but TM was inversely related to high-grade CIN in glands, presum ably due to replacement of metaplastic cells by neoplastic cells. In c onclusion, TM is frequent in patients with lower genital tract patholo gic findings and is often present in locations easily sampled by cytol ogic or biopsy techniques. Awareness of its presence may avoid overint erpretation of TM as endocervical neoplasia.