Ewing Sarcoma as a Second Malignant Neoplasm in an Adolescent After Treatment of Mature B-Cell Lymphoblastic Leukemia

Ewing sarcoma family of tumors (ESFT) has been reported only rarely as a second malignant neoplasm (SMN) after treatment of cancer in childhood, and not at all, to our knowledge, after mature B-cell lymphoblastic leukemia (L3 ALL). We report the first case of ESFT presenting as a SMN at 19 years of age after treatment of L3 ALL in a 14-year-old girl. No predisposition was identified for this association.