Testicular myeloid sarcoma: an unusual presentation of infant acute myeloid leukemia.

Testicular myeloid sarcoma (MS) is a rare disorder; even more so during infancy. There are only 3 cases described previously. We report a 3-month-old baby boy with MS who presented with a testicular mass. This case also features cerebrospinal fluid involvement at diagnosis and bone marrow pathology only detectable by genetic analysis. After completion of the initial treatment, the child relapsed with an MS in the brain and succumbed despite further therapy.