diffuse infiltrating retinoblastoma
Rare variant of retinoblastoma characterized by flat growth pattern without discrete mass formation, often mimicking inflammation.
Full Definition
Diffuse infiltrating retinoblastoma is an uncommon variant representing less than 5% of all retinoblastomas, characterized by a flat, infiltrative growth pattern rather than the typical nodular mass formation. This variant spreads diffusely through the retina and vitreous without forming discrete tumors, often presenting as chronic uveitis, vitreous haze, or pseudohypopyon that is refractory to anti-inflammatory treatment. The diagnosis is frequently delayed due to its masquerade appearance, and the diffuse nature makes complete treatment challenging. Calcification is typically absent, and the tumor may show minimal mass effect on imaging studies. This variant is associated with a poorer prognosis due to extensive intraocular seeding and delayed diagnosis.
Usage
Usage note: Always specify 'diffuse infiltrating' to distinguish from standard retinoblastoma variants.
In Context
- "The chronic uveitis unresponsive to steroids was ultimately diagnosed as diffuse infiltrating retinoblastoma." — Case study report
- "Vitreous biopsy confirmed the suspected diagnosis of diffuse infiltrating retinoblastoma in this masquerade case." — Pathology consultation