title: Gastrointestinal stromal tumors in kidney transplant recipients: Report of two cases and literature review.
abstract: Gastrointestinal stromal tumors (GISTs) are the most common primary mesenchymal gastrointestinal neoplasms. However, GISTs occurring in kidney transplant recipients, including their treatment and outcome, are rarely described in literature. We hereby report two kidney transplant recipients with GISTs. Our first patient was diagnosed with high-risk epithelioid gastric GIST 2 years after kidney transplant. He received everolimus after resection and remained disease-free for 2 years before liver metastasis was confirmed. Imatinib therapy was planned but he died of fulminant pneumonia shortly. Our second patient was diagnosed with spindle cell GISTs in the mesentery 1 year after kidney transplant. Only partial response was obtained with imatinib as new lesions continued to develop. Withdrawal of cyclosporine and introduction of sirolimus resulted in complete shrinkage of existing tumors and no new lesions. He remained disease-free for more than 10 years. Combination therapy consisting of imatinib and inhibitors of mammalian target of rapamycin (mTORi) seems to be safe and effective in kidney transplant recipients. However, therapeutic drug monitoring of mTORi is essential to avoid nephrotoxicity. Further trials addressing the optimal dosage of imatinib and mTORi in kidney transplant recipients are recommended.
authors.affiliation: Department of Medicine, Queen Elizabeth Hospital, Hong Kong SAR.
authors.forename: Chi Yuen
authors.initials: CY
authors.lastname: Cheung
authors.affiliation: Department of Medicine, Pamela Youde Nethersole Eastern Hospital, Hong Kong SAR.
authors.forename: Stanley Hok King
authors.initials: SH
authors.lastname: Lo
authors.affiliation: Department of Medicine, Pamela Youde Nethersole Eastern Hospital, Hong Kong SAR.
authors.forename: Ching Kit
authors.initials: CK
authors.lastname: Chan
authors.affiliation: Department of Medicine, the University of Hong Kong, Hong Kong SAR.
authors.forename: Fu Keung
authors.initials: FK
authors.lastname: Li
authors.affiliation: Department of Medicine, the University of Hong Kong, Hong Kong SAR.
authors.forename: Ignatius Kum Po
authors.initials: IK
authors.lastname: Cheng
authors.affiliation: Department of Medicine, Queen Elizabeth Hospital, Hong Kong SAR.
authors.forename: Ka Foon
authors.initials: KF
authors.lastname: Chau
mesh_terms: D000971:Antineoplastic Combined Chemotherapy Protocols / Q000627:therapeutic use*; D000068338:Everolimus / Q000008:administration & dosage; D046152:Gastrointestinal Stromal Tumors / Q000188:drug therapy* / Q000453:epidemiology*; D006801:Humans; D000068877:Imatinib Mesylate / Q000008:administration & dosage; D016030:Kidney Transplantation; D008297:Male; D020123:Sirolimus / Q000008:administration & dosage; D058570:TOR Serine-Threonine Kinases / Q000037:antagonists & inhibitors
chemical_list: D000068877:Imatinib Mesylate; D000068338:Everolimus; C546842:MTOR protein, human; D058570:TOR Serine-Threonine Kinases; D020123:Sirolimus
keywords: gastrointestinal tumor; kidney transplant