Ophthalmic Pathology and Oncology
Core concepts
Understand the histopathology of common ocular tumors: uveal melanoma, retinoblastoma, lymphoma, and metastatic lesions. Know the clinical signs of retinoblastoma (leukocoria, strabismus) and uveal melanoma (pigmented choroidal mass, exudative detachment). Learn the principles of biopsy and the role of imaging. Understand the difference between benign and malignant lesions: basal cell carcinoma (pearly, telangiectatic), squamous cell carcinoma, and sebaceous carcinoma (pagetoid spread).
Traps
Do not biopsy a suspected retinoblastoma before considering enucleation; avoid seeding. Uveal melanoma can metastasize to the liver. Lymphoma can masquerade as uveitis. Sebaceous carcinoma is often misdiagnosed as chalazion or blepharitis. Know that metastatic lesions are the most common intraocular malignancy in adults.
Rule of thumb
A pigmented choroidal mass with exudative detachment and ultrasound findings suggests uveal melanoma; systemic workup focuses on the liver.
Worked example
An older adult with a pigmented iris lesion and a choroidal mass has ultrasound showing a dome-shaped lesion. This is uveal melanoma; evaluate for metastasis, especially hepatic.