CASE PRESENTATION: This is a case of a 62-year-old female with 70 pack years smoking history who received a bilateral lung transplant for COPD in 2010. Patient presented with fevers, left sided flank pain and increased urination with foul-smelling urine. She was noted to have leukocytosis and mild hyponatremia. A CT of abdomen and pelvis revealed a non-obstructing right kidney stone along with irregular and nodular bladder wall thickening suspicious for urothelial neoplasm. Cystoscopy revealed multiple bladder masses and biopsy demonstrated non-Hodgkin lymphoma consistent with PTLD, monomorphic diffuse large B-cell lymphoma which was EBV negative, positive for CD 10, CD 20, BCL-6, MUM1, and c-MYC (40%). Whole body PET scan revealed an FDG avid prevascular lymph node in the chest; consistent with Stage IV PTLD. Patient received treatment with six cycles of rituximab- cyclophosphamide (Cytoxan), Adriamycin (hydroxydoxorubicin), vincristine (oncovin) and prednisone (R-CHOP) with curative intent and a reduction in immunosuppressive therapy.