Background
Melanoma is a life-threatening malignancy that affects melanocytes
(pigment-producing cells) found throughout the body. Melanomas are of
two types: cutaneous and non-cutaneous. Cutaneous melanomas, which
account for approximately 95% of all melanomas, originate in the
pigment-producing cells of the skin. On the other hand, non-cutaneous
(non-skin) melanomas affect other regions of the body including the eyes
and mucous membranes, such as those present in nasal passages and the
oral cavity.
Although it is a rare disease, uveal melanoma is the most common form of
non-cutaneous melanoma, and it is the most frequent primary cancer of
the eye in the adult [1]. Uveal melanoma is known to affect
~7000 individuals worldwide annually [2], with
incidence rates ranging from 0.2 to 0.3 per million individuals in
African and Asian populations to up to 6 per million in white
populations [3]. Diagnosis usually occurs at age 60, and this cancer
is more prevalent among Caucasians.
In most cases, UM forms in the choroid: the vascular layer of the eye
lying between the sclera and the retina. Symptoms that may be exhibited
by UM patients include but are not limited to: variable and painless
visual disturbances, discoloration of the iris, change the shape of the
pupil, or loss of peripheral vision.