Survival following childhood neuroblastoma is improving with low rates of secondary myeloid neoplasms. We describe a 13‐month‐old male with intermediate risk neuroblastoma who developed an isolated scalp therapy‐related myeloid sarcoma (t‐MS). Developmental delays and two distinct malignancies prompted constitutional evaluation. Chromosomal microarray identified a 7.3 Mb deletion of 9q22.32 to 9q31.1. He remains in remission 11 months following hematopoietic cell transplant. Unusual presentations of rare diseases necessitate a multidisciplinary approach and adaptation of standardized protocols to accommodate increased risks imposed by genetic variants. Pediatr Blood Cancer 2014;61:1701–1703. © 2014 Wiley Periodicals, Inc.