Müllerian adenosarcoma of vagina arising in persistent endometriosis: report of a case and review of the literature.

BACKGROUND: Primary adenosarcoma arising in vaginal endometriosis poses a diagnostic challenge, especially in superficial vaginal biopsies. CASE: A 56-year-old woman, with a prior diagnosis of ovarian endometriosis, presented with a rapidly enlarging mass of the vaginal vault. Two prior biopsies were benign and showed endometriosis. The third vaginal biopsy revealed benign endometriotic glands cuffed by a cellular stroma with moderate cytologic atypia, a histological appearance diagnostic of Müllerian adenosarcoma. A 16-cm vaginal mass that had infiltrated the pelvic structures was resected.
CONCLUSIONS: Close clinical follow-up of extrauterine endometriosis and clinical-pathologic correlation is necessary. Histological features such as cellular stromal cuffing around benign endometriotic glands are critical in arriving at a timely diagnosis of adenosarcoma in patients with persistent extrauterine endometriosis, even in superficial vaginal biopsies.