Epstein Barr virus-associated smooth muscle tumour (EBV-SMT) of the urinary bladder

Epstein-Barr virus-associated smooth muscle tumour (EBV-SMT) is an uncommon, under-recognised but distinct clinicopathological entity that occurs in the setting of immunosuppression. Predisposition of organ transplant patients to smooth muscle tumours was originally recognised by Pritzker et al., in 19701 and the link to EBV infection was first reported by a French pathologist in 1994.2 The following year, two groups of US researchers separately reported on handful of paediatric patients with EBV associated smooth muscle tumours in the setting of organ transplant3 and HIV,4 respectively. To date, over 200 cases have been reported in the English literature. It is seen in post organ or stem cell transplant patients, HIV/AIDS and congenital immunodeficiencies. 1.1. Case presentation A 35 year old woman from Papua New Guinea was referred to our tertiary centre with obstructive urinary tract symptoms. Her symptoms developed during pregnancy over 6 months and required an indwelling catheter for acute urinary retention. Her medical history is significant for positive HIV serology and she is currently on antiretroviral therapy - Lopinavir/Ritonavir (200/50 mg) twice daily and Lumivudine/Tenofovir (300/300 mg) nightly. CD4 count at presentation was 0.43 × 109 and her HIV viral load was 398 RNA/ml. Radiological examination of the pelvis showed a 7.0 × 5.0 cm mass involving the bladder neck and vaginal wall (Fig. 1A–C). Three neoplastic lesions measuring up to 7.9 cm were also identified in the liver on further imaging, raising possibility of a pelvic malignancy with hepatic metastases. Cystoscopy and biopsy were performed and a mobile soft 15 cm mass attached to the right urethral wall, bladder, and vaginal walls was biopsied. Open in a separate window Fig. 1 A) Coronal and B) Axial CT sections of large bladder tumour C) Axial CT Section of hepatic mass.