Pineal malignant neoplasm in association with hereditary retinoblastoma

A patient with unilateral hereditary retinoblastoma who was successfully treated at the age of 7 weeks developed a tumour in the pineal region two and a half years later. The initial response to radiation treatment of the latter lesion was not maintained. Subsequent necropsy findings are described. Clinically and pathologically this case represents an example of the recently described trilateral retinoblastoma. The response to treatment after early recognition was disappointing.