Ewing sarcoma and sinonasal neuroectodermal tumors as second malignant tumors after retinoblastoma and other neoplasms.

BACKGROUND: Excesses of various childhood cancers have been reported after retinoblastoma, including a trickle of Ewing sarcoma (ES) and perhaps histologically similar olfactory neuroblastoma, both of which are neural tumors. To update and advance this information, case reports were sought by an extensive review of the literature. PROCEDURE: The search was made through the use of PubMed, and the Web of Science (Citation Index Expanded), keying on primary references. Three sinonasal cancers diagnosed as ES were immunohistochemically stained for MIC-2 protein (positive in ES).
RESULTS: Retinoblastoma occurred before ES in ten cases (seven bilateral). In four others, retinoblastoma (three bilateral) developed before sinonasal neural tumors (poorly differentiated). ES also occurred after 14 cancers other than retinoblastoma (five lymphomas, four leukemias, and one each of five miscellaneous cancers). The predominance of retinoblastoma prior to ES differs markedly from the low-frequency of retinoblastoma among childhood cancers in the general population. On the contrary, cancers other than retinoblastoma were proportionate to those in the general population. Previously, retinoblastoma followed by excesses of osteosarcoma and soft tissue sarcomas has been attributed to the action of the inherited RB-1 gene. The sinonasal tumors stained negative for MIC-2 protein.
CONCLUSIONS: Heritable retinoblastoma may predispose to ES and perhaps to a subset of poorly differentiated neuroectodermal tumors in the sinonasal region that may be related to olfactory neuroblastoma.