Perivascular epithelioid cell tumour of the vagina in an 8 year old girl.

Perivascular epithelioid cell tumor (PEComa) is a rare mesenchymal tumor with an unpredictable natural history. We present the first reported case of PEComa of the vagina diagnosed in an 8-year-old girl. This was initially diagnosed on biopsy as an embryonal rhabdomyosarcoma, and the patient underwent 3 cycles of chemotherapy according to the Mesenchymal Malignant Tumour 1989 protocol. A repeat scan, however, revealed an increase in tumor size. Total resection was achieved via a transvaginal (vertical sleeve) partial vaginectomy. The resected tumor had the typical appearance of a PEComa. Immunostains showed positive staining of tumor cells for HMB45, neuron-specific enolase, and calponin but were negative for S100 protein, melaninA, chromogranin, smooth muscle actin, desmin, caldesmon, epithelial membrane antigen, AE1/3, and synaptophysin. Six months after surgery, she remains free of tumor and is on follow-up with regular local examinations under anesthesia and computed tomography scans. Our case highlights the importance of an accurate initial diagnosis, and we stress the importance of regular surveillance over a significant period.