Myeloid Sarcoma of the Bladder in a Patient with Chronic myelomonocytic Leukaemia

Abstract

BackgroundMyeloid sarcoma is a rare extramedullary tumour of immature granulocytes, most commonly involving the skin, bone, lymph nodes, and soft tissue. It is usually associated with a diagnosis of relapsed or de novo acute myeloid leukaemia, acute lymphoblastic transformation of a myelodysplastic/myeloproliferative neoplasm, or can occur as isolated myeloid sarcoma.Case reportA 66-year-old female with a 7-year history of stable chronic myelomonocytic leukaemia presents with urgency, frequency, dysuria symptoms, and without new constitutional symptoms. She is found to have atypical, multifocal lesions on the right posterolateral wall of the bladder with associated hydronephrosis. Pathology reveals the diagnosis as myeloid sarcoma; surprisingly, bone marrow evaluation does not show evidence of acute leukaemic transformation.ConclusionsMyeloid sarcoma occurring in patients with chronic myelomonocytic leukaemia is extremely rare, and there are no cases reported in the English literature of these patients developing lesions in the bladder. The urological manifestations of an underlying haematological malignancy are best managed with a combination of systemic chemotherapy and allogeneic stem cell transplant, and in this case, the only surgical intervention required was ureteric stenting and tissue biopsy. Although rare, it is essential to consider alternative diagnoses when confronted with an atypical bladder tumour; failure to do so may result in patient harm by exposure to unnecessary intervention and delay to potentially curative treatment.