Phthisis bulbi: clinical and pathologic findings in retinoblastoma.

PURPOSE: Phthisis bulbi represents an ocular end-stage disease characterized by shrinkage and disorganization of the eye. We aim at identifying the pathologic changes of phthisis bulbi associated with retinoblastoma. DESIGN: Retrospective observational case series study. METHODS: 16 enucleated eyes were enrolled retrospectively between 2007 and 2012. Pathologic gross and microscopic findings were assessed. RESULTS: Cases showed grossly shrunken eyes with a mean volume of 4.3 cc. Sclera was markedly thickened in the majority of cases with mean of 2272.8 µ. Choroid showed an average thickness of 1029 µ. Necrosis, dystrophic calcification, ossification, gliosis, residual viable tumor was identified in many cases. Pathologic high risk factors were seen in three specimens. CONCLUSIONS: We conclude that retinoblastoma must be considered in the differential diagnosis of phthisis bulbi in the pediatric patients and active tumor was present in half of the patients.

Multiplex ligation-dependent probe amplification versus fluorescent in situ hybridization for screening RB1 copy number variations in Egyptian patients with retinoblastoma.

BACKGROUND: Retinoblastoma (RB) is the most common primary intraocular malignant tumor in children. RB is mostly caused by biallelic mutations in RB1 and occurs in hereditary and non-hereditary forms according to the "two-hit" theory. RB1 mutations comprise point mutations, indels, large deletions, and duplications. Genetic testing is essential for the comprehensive treatment and management of patients with RB. AIM: The aim was to evaluate RB1 copy number variations (CNVs) using MLPA versus FISH assays in group of Egyptian patients with RB. RESULTS: 16.67% showed an RB1 deletion, abnormal methylation status, or both. CONCLUSION: Our results suggested MLPA is a fast, reliable, and powerful method and should be used as a first-line screening tool for detecting RB1 CNVs in patients with RB. Moreover, MLPA is advantageous as it evaluates the methylation status/inactivation of RB1, not possible by FISH.