Most endocervical adenocarcinomas ( approximately 90%) are high-risk human papillomavirus (HPV)-related neoplasms, with the remainder being unrelated to HPV; both types infrequently metastasize to the ovaries. Clinicopathologic features of 29 cases of synchronous and metachronous endocervical and ovarian tumors (26 HPV-related, 3 unrelated to HPV) were analyzed. In 18 cases, the cervical tumors were clearly invasive; these included 5 clinically evident tumors diagnosed before the ovarian metastases (immediately preoperatively to 7 y), 11 clinically unsuspected tumors diagnosed concurrently in specimens obtained for evaluation of ovarian/pelvic masses, 1 case with concurrent clinically evident cervical and ovarian masses, and 1 clinically occult tumor diagnosed subsequent to the ovarian metastasis. In 11 cases, the cervical tumors were more limited; these included 5 tumors comprised predominantly of adenocarcinoma in situ with small foci of superficial invasion ("microinvasive carcinomas") diagnosed before the ovarian metastases (3 mo to 7 y) and 6 tumors comprised of extensive adenocarcinoma in situ lacking unequivocally recognizable stromal invasion diagnosed before (9 mo to 7 y, n=4), concurrently with (n=1), or subsequent to (n=1) the ovarian metastases. Fifteen cervical tumors involved lower uterine segment corpus endometrium or endomyometrium, including 4 tumors that were minimally invasive or not recognizably invasive in the cervix. The ovarian tumors ranged in size from 2.1 to 30.0 cm (mean/median=12.7/13.5); they were unilateral in 19 cases (65.5%) and 12 of these were unilateral and 10 cm or greater. In 26 cases, including the 19 unilateral tumors, the ovarian tumors exhibited "borderlinelike," confluent glandular, cribriform, and/or villoglandular patterns simulating primary ovarian atypical proliferative (borderline) tumors or well-differentiated carcinomas; these patterns were pure in 24 and admixed with minor infiltrative foci in 2. The ovarian tumors had features typical of metastases (bilateral and infiltrative) in only 3 cases. In all HPV-related cases the paired endocervical and ovarian tumors contained identical HPV types, establishing the ovarian tumors as metastases. Endocervical adenocarcinomas, including microinvasive forms and some not recognizably invasive, have the potential to metastasize to the ovaries; extension into the lower uterine segment/corpus endometrium may be a risk factor, with retrograde uterine/transtubal spread as a possible mechanism.