Vaginal mass in a 13-year-old girl.

A 13-year-old girl, otherwise healthy, presented with complaints of a painless vaginal mass associated with intermittent abnormal vaginal bleeding and discharge over a few weeks. External examination of genitalia was unremarkable and pubertal development was appropriate for her age. No obvious abnormality was detected on rectoabdominal examination. No transvaginal examination was attempted in view of the patient's age and she was directly referred to a trans-perineal ultrasound scan that showed an ill-defi ned lobulated heterogeneous vaginal mass. On further evaluation with dynamic contrast magnetic resonance imaging (MRI) of the pelvis, a lobulated polypoid mass was noted protruding from the cervical orifi ce into the upper two thirds of the vagina. This mass demonstrated heterogeneous high T2 (Fig. 1a) and low T1 (Fig. 1b) signal intensity with mild central enhancement on delayed post contrast sequences (Fig. 1c). The rest of the pelvic organs were unremarkable. Later, the patient underwent vaginal examination under anaesthesia followed by colposcopy and hysteroscopy that showed a fl eshy polypoidal mass protruding from the endocervix into the vagina, which was subsequently resected. The vagina and uterine cavity were found to be unremarkable. What is the diagnosis of the mass? A. Benign endocervical polyp B. Mullerian adenosarcoma C. Embryonal rhabdomyosarcoma D. Endometrial stromal sarcoma E. Haemangioma/venous malformation