Most common clinical presentation of retinoblastoma:
Ans. d. Leukocoria + strabismus (Ref: Kanski 7th/510-517; Yanoff's 3rd/887-889; Khurana 4th/281-283)Most common clinical presentation of retinoblastoma is Leukocoria and strabismus.The most common mode of spread of retinoblastoma is by optic nerve invasion. Direct extension by continuity to the optic nerve and brain is common."Retinoblastoma is a primary malignant intraocular neoplasm that arises from immature retmoblasts within the developing retina. It is the most common primary intraocular malignancy of childhood in all-racial groups. The neoplasm has strong tendencies to invade the brain via the optic nerve and metastasize widely. "--Yanoff and Duker 4/e p793RetinoblastomaRetinoblastoma is common congenital malignant tumor arising from the Neurosensory retinaQMC congenital intraocular tumor of childhoodQOccurring 1 in 15,000-20,000 live birthsThough congenital, usually seen between 1-2 years of ageQBilateral in 25-30% cases90% are sporadic; 10% are familialGenetics:Rb gene is located on chromosome 13q14QRb gene is a tumor suppressor gene, deletion or inactivation of this protective gene by two mutations (Knudson's two hit hypothesis) results in retinoblastomaQPathology:Origin: Arises as malignant proliferation of the immature retinal neural cells called retinoblastsCharacterized by Flexner-Wintersteiner rosettes (highly specific for retinoblastoma). Homer-Wright rosettes, pseudo rosettes and fleurettes formationQPresence of areas of hemorrhage and necrosisClinical Features:Quiescent stageGlaucomatous/ Inflammatory stageStage of Extra-ocular extensionStage of Distant Metastasis* MC presenting feature: Leukocoria(amaurotic cat's eye appearance)Q* 2nd MC presenting feature: Squint (convergent)Q* Nystagmus is a rare feature, noted in bilateral cases* Defective vision is very rare* Endophytic retinoblastoma: Cottage cheese appearanceQ* Exophytic retinoblastoma: Exudative retinal detachment appearanceQ* Untreated retinoblastoma during quiescent stage may present with severe pain, redness and wateringQ* Due to progressive enlargement of tumor, the globe bursts through the sclera, usually near the limbus* Followed by rapid fungation and involvement of extra- ocular tissues resulting in marked proptosisQ* Lymphatic spread first occurs in preauricular lymph nodesQ* Direct extension by* continuity to the optic nerve and brain is commonQ* Metastasis by bloodstream involves cranial and other bonesDiagnosis:X-ray orbit: Calcification in 75% casesQRaised LDH in aqueous humorCT: Extension to optic nerve, orbit and CNSTreatment:Tumor destructive therapyEnucleation is treatment of choice when* For early stage (tumor involves less than half of retina and optic nerve is not involved)* Primary systemic chemotherapy (Vincristine, car- boplatin and etoposide) followed by local therapy (cryotherapy, laser photocoagulation, thermotherapy)* Tumor involves more than half of retina Optic nerve is involved* Glaucoma is present and anterior chamber is involved* Eye-ball is enucleated along with maximum length of optic nerve taking special care not to perforate the eye ball.Indications of Palliation (Chemotherapy, surgical debulking, EBRT)Retinoblastoma with orbital extensionRetinoblastoma with intracranial extensionRetinoblastoma with distant metastasisPoor prognostic factors* Optic nerve involvementQ* Undifferentiated tumor cellsQ * Massive choroidal invasionQReese-Ellsworth classification to predict survival of the eye with retinoblastomaQ
Leukocoria + heterochromia iridis
Leucokoria + pseudohypopyon
Leukocoria + hyphema
Leukocoria + strabismus
Intra Ocular Tumour