Deep nabothian cysts of the uterine cervix. A possible source of confusion with minimal-deviation adenocarcinoma (adenoma malignum).

Four cases in which nabothian cysts extended deeply into the cervical wall are described. Well differentiated adenocarcinoma of the minimal-deviation type (adenoma malignum) was an initial diagnostic consideration in three of them. The cysts were incidental findings in patients 32 to 79 years of age, who underwent hysterectomy for uterine leiomyomas (two cases), uterine prolapse (one case), and a leiomyosarcoma of the pelvic soft tissues (one case). Gross examination of the cervix in each case revealed multiple mucin-filled cysts that extended almost to the serosa or paracervical connective tissue. On microscopic examination, the cysts were characteristic of nabothian cysts, being lined by columnar to flattened endocervical-type cells devoid of atypical features or mitotic activity. Postoperative follow-up, available in three patients, was uneventful over periods of 1, 6, and 10 years. Deep nabothian cysts are an uncommon nonneoplastic lesion of the cervix that is important to distinguish from adenocarcinoma.