To analyze the histopathology and expression of transforming growth factor β (TGF-β) in retinoblastoma with and without cataractous changes.
Twenty patients with unilateral retinoblastoma underwent enucleation. None of these patients had received preoperative chemotherapy or radiotherapy. Formalin-fixed, paraffin-embedded tissue sections were examined histologically for the presence of morgagnian globules or liquefaction of lens fibers; TGF-β was immunolocalized using an anti-TGF-β antibody.
Two globes showed several morgagnian globules and liquefaction of the lens fibers, representing cataractous changes. One patient had posterior subcapsular cataract; the other, anterior polar cataract. In both cases, prominent cytoplasmic immunoreactivity for TGF-β was detected in retinoblastoma cells. In contrast, 3 patients showed histologic evidence of minor cataractous changes. The globes with either minor or no cataractous changes revealed minimal to no expression of TGF-β.
These results suggest that TGF-β produced by retinoblastoma cells may induce cataract formation.
The growth factors produced by retinoblastoma cells may lead to associated pathologies, such as cataracts, in the ocular structures. This study implies that when a child presents with a unilateral cataract, retinoblastoma should be excluded as the primary diagnosis.