Sinonasal adenocarcinoma: a rare second malignancy in long term retinoblastoma survivors.

Retinoblastoma is the most common primary cancer of the eye in children. The incidence of second tumors in survivors of bilateral retinoblastoma and in survivors of unilateral retinoblastoma who presumably carry a germline RB1 mutation is documented. This article describes the previously unrecognized association of sinonasal adenocarcinoma as a second malignancy in retinoblastoma survivors. We present three cases who received radiation therapy as a part of their treatment and developed sinonasal adenocarcinoma as a second malignancy. Sinonasal adenocarcinoma should be considered as a second malignancy in retinoblastoma survivors who present with vague sinus symptoms.