Supplementary Material for: Clinical course of a rare Epstein–Barr virus-associated smooth muscle tumor and its genomic analysis

Epstein–Barr virus (EBV) can rarely induce smooth muscle tumors (SMTs). A 20-year-old female patient underwent kidney transplantation for renal failure. Since then, she has been treated with immunosuppressants, including a calcineurin inhibitor, tacrolimus, and prednisolone, owing to the immunological rejection. Three years later, she developed large liver tumors (diameter > 5 cm) and multiple small lung tumors that were identified as EBV-SMTs based on the results of liver biopsy/histopathology. No intervention was performed, except for the addition of an mTOR inhibitor, everolimus, which inhibits both immune reaction and SMT growth. Finally, after 8 years, the transplanted kidney became nonfunctional and immunosuppressant administration became unnecessary as urinary dialysis was started. Under these circumstances, SMT growth was observed despite the absence of immunosuppressant administration. Three months after the cessation of the immunosuppressants, EBV-SMTs in the liver and lungs shrank slightly. To the best of our knowledge, this is the first report on the genomic profile of this rare tumor. The clinical course of our patient indicates that EBV can induce SMTs, and immunological suppression of EBV may inhibit the activity of these tumors.

EB病毒（Epstein–Barr virus，EBV）极少诱发平滑肌肿瘤（smooth muscle tumors，SMTs）。一名20岁女性患者因肾衰竭接受肾移植术，术后因免疫排斥反应，需接受包括钙调磷酸酶抑制剂（calcineurin inhibitor）他克莫司（tacrolimus）与泼尼松龙（prednisolone）在内的免疫抑制治疗。术后3年，患者出现直径＞5cm的巨大肝脏肿瘤与多发肺部小结节，经肝活检/组织病理学检测证实为EBV相关平滑肌肿瘤（EBV-SMTs）。后续仅加用了可同时抑制免疫反应与平滑肌肿瘤生长的哺乳动物雷帕霉素靶蛋白抑制剂（mTOR inhibitor）依维莫司（everolimus），未采取其他干预措施。8年后，移植肾丧失功能，启动尿液透析后无需再服用免疫抑制剂。在此情况下，尽管已停用免疫抑制剂，患者的平滑肌肿瘤仍出现生长。停用免疫抑制剂3个月后，患者肝脏与肺部的EBV-SMTs体积略有缩小。据我们所知，本研究为首例针对该罕见肿瘤的基因组特征分析报告。本病例的临床病程提示，EB病毒可诱发平滑肌肿瘤，而针对EB病毒的免疫抑制或许可抑制此类肿瘤的增殖活性。