Background: In contrast to Epstein-Barr virus (EBV)-associated posttransplant lymphoproliferative disorders (PTLD), EBV-associated leiomyomatous tumors have thus far only rarely been described.
Case report: Two years after heart transplantation with ATG induction, cyclosporine (CsA; trough levels of 250 ng/mL)-based triple drug immunosuppression), a 23-year-old patient developed a small round lesion within the left lateral liver segment. The patient underwent ultrasound-guided biopsy followed by liver resection. Histological and immunohistological examination showed a leiomyosarcoma. In situ hybridization using EBV-specific EB endoplasmic reticulum-RNA showed an intensive signal in almost all tumor cells. The tumor stained for EB nuclear antigen (EBNA)-2-protein. Immunosuppression was drastically reduced, namely, CsA levels <100 ng/dL, prednisolone 5 mg, azathioprine withdrawn, and antiviral chemotherapy initiated with 10 days of IV gancyclovir and acyclovir followed by oral famcyclovir. During the follow-up, anti-EBV-IgM, anti-early antigen antibodies, and anti-EBNA antibodies were continuously monitored excluding significant EBV replication. Eighteen months post-liver resection, and high-resolution computed tomography scan demonstrated two paravertebral tumors. These lesions and a small nodule at the left ankle were resected revealing identical leiomyosarcomata. Immunosuppression was further reduced (CsA levels 75 ng/dL) and famcyclovir maintenance therapy started. Nevertheless, 2 years later the patient again developed tumor recurrence (perirectal, liver, and right adrenal gland); the tumors were surgically removed. The therapy was switched to Rapamycin and famcyclovir was continued. Three years after the last surgical intervention, the patient is well and recurrence-free.
Conclusion: Long-term survival in patients with posttransplant EBV-associated leiomyosarcoma can be achieved by combined surgical intervention, reduction of immunosuppression, switch to Sirolimus, and antiviral chemotherapy.