Chloroma of the testis after allogeneic peripheral blood stem cell transplantation: a case report.

Chloroma, or granulocytic sarcoma, is a rare extramedullary solid hematologic cancer that affects many sites, usually in concert with acute myeloid leukemia. It is infrequently associated with other myeloproliferative disorders or chronic myelogenous leukemia. Chloroma of the testis after allogeneic bone marrow transplantation is particularly sparsely represented in the literature. It is often incorrectly diagnosed as malignant lymphoma, especially large-cell lymphoma, owing to the similarity of the histologic morphology, scanty eosinophilic myelocytes, and no or overlooked history of leukemia. Although erroneous diagnosis is decreasing with the advent of ancillary studies, the diagnosis of chloroma continues to be a nightmare for pathologists. It is thus suggested that an appropriate panel of marker studies be performed in conjunction with clinical correlation and circumspection to avoid reaching a misleading conclusion and improper treatment of patients. We report an interesting case of a 35-year-old male with a clinical history of chronic myelogenous leukemia post allogeneic peripheral blood stem cell transplantation and complete molecular remission, who was found to have chloroma of the left testis.