Retinoma
C. Request genetic testing and monitor
Retinoma is a white-gray gelatinous retinal tumor with chalky calcification that resembles retinoblastoma but lacks aggressive intraocular or systemic behavior.1,2 Key features distinguishing retinoma from retinoblastoma include underlying chorioretinal changes, indicative of a chronic and quiescent state, and absence of vascularization or subretinal fluid.1- 4 Vitreous seeds may seldomly accompany retinomas as inactive spheres floating in the vitreous in front of the retina, carrying an uncertain clinical significance that contrasts to retinoblastoma seeds, known to represent worse disease staging and prognosis.3,5
While retinoblastoma is mainly diagnosed in the first months or years of life by the presence of leukocoria and strabismus, retinomas can be detected incidentally during fundoscopy at any age, being more commonly discovered in relatives of patients with retinoblastoma.1- 3 Indeed, molecular studies using samples from eyes with simultaneous retinoma and retinoblastoma demonstrated that the retinoma areas in these patients exhibit inactivation of both RB1 alleles similar to the retinoblastoma areas, missing the additional variant events required for full-spectrum retinoblastoma.6 For this reason, a new case of retinoma should be promptly screened for RB1 gene variation (choice C) to allow adequate patient counseling and guidance for testing of relatives.2,6 The lifelong risk for retinoma transformation into retinoblastoma in the general population has been estimated at up to 15% in 20 years.3