Abstract
Purpose: :
To investigate whether choroidal melanoma (CM) seen at King Khaled Eye Specialist Hospital (KKESH) in Saudi Arabia exhibit clinical differences compared to what is known from the literature for CM in Caucasians in the United States (USA) , in an effort to identify potential differences particularly related to metastasis and mortality outcomes
Methods: :
Retrospective chart review of patients with CM seen at KKESH between 1983 and 2010
Results: :
A total of 120 patients were identified with an apparent incidence much lower than that in the Caucasian population. Thirty out of 120 records were reviewed to date. All patients were Middle Eastern except for two, only one had a blue colored iris, and all lesions were unilateral. The age ranged from 24 to 74 years (average 48.4 years). None had metastasis at the time of initial presentation. Associated findings on examination included retinal detachment in 22 eyes (73%) and neovascular glaucoma in one. The CM was pigmented in all but three eyes (90%), mushroom shaped in 14 eyes, dome shaped in 15, and multi-lobulated in one. The most common site of involvement was the temporal area in 15/30 eyes (50%). The ultrasound lesion thickness ranged from 3.24 to 15.5mm (average 8.4mm) and 26 lesions (87%) had low to medium internal reflectivity. Treatment included I-125 radioactive plaque in 5 eyes, proton beam in one, transpupillary thermotherapy in one and enucleation in 23 eyes (77%). Out of the 23 enucleated eyes, 7 could have been treated with brachytherapy based on lesion characteristics, but enucleation was elected for other reasons, for a total of 16/30 eyes (53%) that required enucleation based on lesion characteristics. Among the 23 enucleated eyes, the most common cell type was spindle in 13 eyes (56%), followed by the mixed and the epithelioid type in 5 eyes each. Two eyes had extrascleral extension and another 2 had optic nerve invasion. None of the 30 patients developed metastasis or tumor-related mortality over an average follow up of 69.7 months.
Conclusions: :
CM at KKESH has different characteristics and treatment outcomes as compared to that in Caucasians in the USA including a lower incidence, a younger age at diagnosis, a predominantly large size at presentation, treatment with enucleation in the majority of cases, predomination of the spindle cell type lesions, more frequent optic nerve invasion, and an apparent lower metastasis/mortality rate. Understanding the etiology of such differences can lead to better insight into differences in the pathobiology and cytogenetics of the tumor, which in turn may reveal new pathways for targeted therapies.
Keywords: melanoma • tumors • clinical (human) or epidemiologic studies: treatment/prevention assessment/controlled clinical trials