Retinoblastoma is a malignant tumor of primary intraocular found in children, especially in the under 5 years of age. Tumors derived from embryonic retinal tissue, may be unilateral (70%) and bilateral (30%). Most cases of bilateral nature herediten inherited via chromosome.
Tumor mass can grow into the vitreous (endophytic) and grow through the lining of the retina or into the sub retinal space (endophilic). Sometimes the tumor develops diffuse.
Endophytic growth is more common. Endophytic tumors arise from the core layer in the nerve fiber layer and a layer of retinal ganglion. Exophillic type arises from the outer core layer and can be seen as a solid retinal detachments.
Expansion of the ocular retina into the vitreous tumor can occur in endophilic type and distribution of metastases may occur via subretinal spatium or through the vitreous tumor. In addition, the tumor can spread through infiltration in the lamina cribrosa directly to the optic nerve with extension into the choroid layer can be found infiltration of veins in the area with hematogenous metastasis to bone and bone marrow. This eye tumor, divided into stage IV, respectively:
- Stage I: indicates the tumor is confined to the retina (the quiet stage).
- Stage II: the tumor is confined to the eyeball.
- Stage III: There are extra ocular regional expansion, both of which go beyond the tip of the optic nerve were cut when enucleation.
- Stage IV: distant metastases are found in the brain.
