Choroidal melanomas with a collar-button configuration: response pattern after iodine 125 brachytherapy

Area of Science:

• Ophthalmology
• Oncology
• Radiation Therapy

Background:

• Choroidal melanomas are intraocular tumors requiring effective treatment.
• Brachytherapy, specifically Iodine-125, is a treatment modality for choroidal melanoma.
• Tumor response patterns after treatment can vary and require detailed characterization.

Purpose of the Study:

• To describe a distinctive postbrachytherapy response pattern in choroidal melanomas exhibiting a collar-button configuration.
• To analyze the evolution of the collar-button morphology and associated vitreous changes following treatment.

Main Methods:

• Review of 93 eyes with choroidal melanoma treated with Iodine-125 brachytherapy before 1991.
• Identification of melanomas with a collar-button configuration.
• Analysis of postbrachytherapy response patterns and clinical characteristics during follow-up.

Main Results:

• Thirty-four of 93 eyes had melanomas with a collar-button configuration.
• In 47% of these cases, the collar-button persisted while the tumor body shrank.
• The collar-button darkened, and pigmented debris, potentially containing melanoma cells, was observed in the vitreous.

Conclusions:

• A distinct postbrachytherapy regression pattern exists for melanomas with a collar-button configuration.
• This pattern involves persistent, darkening collar-button and shedding of pigmented vitreous debris.
• Characterizing vitreous debris is crucial for differentiating melanoma cell invasion from nonmalignant material.