Unusual acute promyelocytic leukemia following de novo renal transplant: case report and literature review.

Acute promyelocytic leukemia (APL) with transcripting three isoforms of mRNA from PML-RAR alpha fusion genes following renal transplantation has never been reported in the literature. A 39-year-old man received a cadaveric renal allograft for IgA chronic kidney disease in 2006 and was consecutively immunosuppressed by tacrolimus, mycophenolate mofetil, and prednisolone. In 2008, he presented with gum bleeding and weight loss. Following bone marrow biopsy, we diagnosed acute promyelocytic leukemia. Molecular analysis demonstrated atypical presence consisting of three isoforms of mRNA from PML-RAR alpha fusion genes. The patient was administered with three courses of consolidation chemotherapy plus atretinoin, resulting in complete remission and did not jeopardize his allograft function. This novel finding suggests that the leukemogenesis of APL may be polyclonal, sharing similar progenitor targeting on complicated karyotypes, responding well to current chemotherapy.