Uterine adenomyoma: a clinicopathologic review of 26 cases and a review of the literature.

The aim of this study is to highlight the importance of diagnosing uterine adenomyoma and help in differentiating it from other sinister lesions. Adenomyoma of the uterus is a circumscribed nodular aggregate of benign endometrial glands surrounded by endometrial stroma with leiomyomatous smooth muscle bordering the endometrial stromal component. It may be located within the myometrium, or it may involve or originate in the endometrium and grow as a polyp. A retrospective analysis of 26 consecutive cases of uterine adenomyomas diagnosed in the Department of Pathology, Government Medical College, Chandigarh from January 1994 to December 2004 was done, and their clinical and histological features were analyzed. The criterion used for case identification was a circumscribed mass composed of benign endometrial glands with a stromal component consisting of endometrial type stroma surrounded by leiomyomatous smooth muscle. Mitotic figures were counted within 50 high-power fields (hpf) and recorded as the highest number per 10 hpf. The age of the patients ranged from 22 to 60 years (mean age, 41 years). The most common presenting symptom was abnormal vaginal bleeding (n = 15). Thirteen patients underwent panhysterectomy; 7, total hysterectomy; 1, subtotal hysterectomy; 4, polypectomy or tumor removal; and 1, curettage. Of the 26 cases of adenomyoma, 24 were in the corpus, 1 was in the cervix, and 1 was in the broad ligament. An associated leiomyoma was noted in 12 cases (46.9%). The adenomyomas were firm in consistency and, on cut section, showed a gray-white surface. Five tumors showed cystic spaces filled with dark brown material. On microscopic examination, the tumors were well demarcated from the surrounding structures. The endometrial glands were mostly tubular and showed relatively regular spacing from each other without any back-to-back arrangement. The glands were lined by benign proliferative pseudostratified columnar epithelium. An occasional typical mitotic figure was noted in these glands in a few cases. The glands were surrounded by endometrial stroma which was compact and spindly. This stroma was, in turn, bordered by leiomyomatous smooth muscle. Thick-walled blood vessels were commonly observed. One to two typical mitotic figures per 10 hpf were noted in the endometrial stroma in few cases; however, no mitosis was noted in the myometrial component. Associated adenomyosis was also noted in 8 cases (30.8%). Adenomyomas have to be distinguished from a number of other lesions, for example, adenomyosis, leiomyoma with entrapped glands, atypical polypoid adenomyoma, endometrial polyps, adenofibroma, and adenosarcoma. This study highlights the importance of correctly identifying this fairly common entity and helps to distinguish adenomyoma from other similar appearing benign and malignant lesions.