A Rapidly Enlarging Forehead Mass in a Young Retinoblastoma Survivor.

A man in his 20s had a lump on the right side of his forehead. His medical history was notable for bilateral retinoblastoma when he was an infant, which was treated with righteye enucleation and left-eye irradiation. As a teenager, he developed an advanced malignant small bluecell tumor,whichwas interpretedasanolfactoryneuroblastomaandtreated with radiation and chemotherapy. On examination, the patient had a hard, fixed, rounded 2-cm lesion in the right supraorbital region. Computed tomography (CT) showedan irregular mass in the right frontal, maxillary, and ethmoid sinuses with surrounding sclerotic and erosivebonychanges.A fine-needleaspirate (FNA) revealedatypical,mitotically activecells. Boneshavingsobtainedoperativelywere interpretedaschronic sinusitiswithscleroticbone. The surgical specimen showedmultinucleated giant cells and bizarre stromal cells suggestive of treatment effect (Figure, A) and normal-appearing bone. A second opinion was reported as chronic sinusitis and atypical stromal cells. When the patient returned 2months laterwith increasingpain, endoscopy revealedapolypoid lesionoccupying thebiopsiedsite. On repeated operative biopsy, histologic examination showed similar giant cells and atypical stromal cells (Figure,B).However, other areasdemonstratedosteoid formationwith fine calcifications and severely atypical spindle cells with mitotic figures (Figure, C), as well as osteoid-entrapped, malignant-appearing cells (Figure, D). First operative biopsy A Second operative biopsy B