Epstein Barr Virus Associated Smooth Muscle Tumors in Pediatric Heart
Transplantation Patients: A Case Series and Review
Abstract
Background: Epstein-Barr virus associated smooth muscle tumors (EBV-SMT)
are rare neoplasms that occur in immunocompromised individuals. Although
generally less aggressive in adults, data in pediatric solid organ
transplant (SOT) recipients suggest these malignancies may be more
difficult to manage. As pediatric SOT becomes more common, the
occurrence of EBV-SMT is likely to increase. Understanding what incites
and drives these tumors is paramount. Design/Methods: We retrospectively
reviewed the electronic health record (EHR) of 152 pediatric cardiac
transplant recipients at our single institution between 1985-2017. Three
patients were identified as having EBV SMT. We reviewed their
demographics, time to malignancy, histology, treatment, and subsequent
course. Results: Of the 152 cardiac transplant recipients reviewed at
our institution between 1985-2017, three were identified to have EBV SMT
(confirmed by EBER CISH). In our series, the average time to diagnosis
was approximately 32 months following transplant. Liver was the most
common site of EBV SMT. Two patients were diagnosed with EBV SMT after a
known PTLD diagnosis. All three patients had elevated EBV titers at (or
around) time of diagnosis, and there was one patient with EBV
donor/recipient mismatch. Treatment was individualized and varied case
by case. Conclusion: EBV-SMTs are rare in pediatric SOT and are
difficult to manage in the setting of required immunosuppression. While
there is some literature to suggest the use of mTOR inhibition and CTL
therapy is helpful in treatment of EBV SMT, data remains limited given
the paucity of cases. At current, there remains no standard of care for
treatment of pediatric EBV SMT.