Retinoblastoma in an Adult.

Retinoblastoma is a rare malignant tumor of the retina usually seen in children before 5 years of age. The tumor is extremely rare in adults. We report here an unusual case of retinoblastoma in a 55-year-old adult female who presented to us with an orbital mass at a late stage of the disease. Detailed laboratory investigations and imaging studies could not make a precise diagnosis. The treating ophthalmologist suspected primary intraocular tumor, metastatic carcinoma, malignant melanoma, or lymphoma and referred the patient for fine needle aspiration cytology (FNAC). Cytopathological examination of Giemsa-stained FNAC smear was consistent with that of retinoblastoma and established the diagnosis.