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Updated: Feb 6, 2026

Establishment and Propagation of Human Retinoblastoma Tumors in Immune Deficient Mice
Published on: August 4, 2011
Lurking below: massive choroidal invasion under a calcified tumor after attempted conservative therapy for
Kaitlin Kogachi1,2, Jonathan W Kim1,2, Sarah Green3
1a USC Roski Eye Institute, Department of Ophthalmology , University of Southern California , Los Angeles , CA , USA.
Background:
In the conservative management of retinoblastoma, detection of tumor activity beneath large, calcified tumors presents a challenging aspect of care as local consolidation is limited in this area. Routine imaging modalities, including magnetic resonance imaging, B-scan ultrasound, and optical coherence tomography, are also limited in providing appropriate surveillance for recurrent disease.
Materials And Methods:
Medical records were reviewed to evaluate patients' demographic data, ophthalmic exams, imaging studies, and histopathologic reports.
Results:
Three patients (two females and one male) were diagnosed with retinoblastoma (two bilateral and one unilateral) and managed with intravenous chemotherapy and local consolidation. In all three cases, the initial tumors regressed to form large, predominantly calcified tumors. However, it was observed that there continued to be nodular recurrences on the surface of the calcium without visible clinical activity at the base of the calcified lesion. All three cases ultimately required enucleation for these active nodular recurrences and massive choroidal invasion was noted under the calcified tumor. Ophthalmic exams and imaging studies did not provide consistent indication of choroidal disease in these cases, and the extensive calcification prevented detection of active disease at the tumor base on fundoscopy.
Conclusions:
Active choroidal disease at the base of large, calcified tumors cannot be ruled out with ophthalmologic examination and noninvasive imaging; suspicion of disease activity at the base should remain high for patients presenting with multiple recurrent nodules over a calcified tumor.
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