Uveal Melanoma

Background

• Uveal melanoma is a rare type of melanocyte tumor that occurs within the uveal tract of the eye, which encompasses the iris, the choroid, and the ciliary body. Melanoma of the choroid is the most common, accounting for 85%-90% of uveal melanomas.
• While patients with fair skin or hair may be at increased risk to develop uveal melanoma, it is unclear if ultraviolet radiation is a risk factor for uveal melanoma, as it appears to be for cutaneous melanoma. Unlike cutaneous melanoma, the incidence of uveal melanoma over the past 30 years appears stable.
• Uveal melanoma presents most commonly in middle-aged adults with nonspecific eye symptoms, such as a painless change in vision or the visual field, eye pain, iris discoloration, or chronic conjunctivitis. In about 30% of cases, uveal melanoma is identified on routine exam in an asymptomatic patient.
• Although metastases are present in < 5% of patients at initial diagnosis, within a median of 5 years, about 50% will develop metastases (most commonly within the liver). Certain clinical factors, such as larger size of the tumor at diagnosis, and certain genetic factors, such as monosomy of chromosome 3, increase the risk of metastatic spread.

Evaluation

• Patients with pigmented ocular masses should be referred for evaluation by an ophthalmologist experienced in ocular tumors.
• Choroidal or ciliary body melanoma typically appears as a well-demarcated, brown or yellow mass in the retina. Findings suspicious of melanoma include thickness that is > 2 mm, subretinal fluid, orange pigment, and a margin near the optic nerve.
• Iris melanoma may appear as a well-demarcated, usually brown, or sometimes yellow spot on the iris.
• The diagnosis of uveal melanoma is usually based on clinical exam in conjunction with typical findings on ocular ultrasound showing a dark, acoustically hollow lesion, with no halo.
• For evaluation of suspected ciliary body melanoma, consider ultrasound biomicroscopy or anterior segment optical coherence tomography (Weak recommendation).
• Consider systemic workup to evaluate for metastases prior to primary treatment in all patients with a clinical diagnosis of uveal melanoma (Weak recommendation).

Management

• Choice of therapy should be guided by tumor size, lesion location, potential comorbidities of the patient, and patient preference.
• For primary treatment of medium-to-large uveal melanoma, first-line options include brachytherapy or enucleation (Strong recommendation). Brachytherapy appears to have similar 5-year survival rates as enucleation, and allows for globe-sparing, and the potential for maintenance of some vision.
• Consider cytogenetic analyses of tumor tissue (obtained either by fine needle aspiration biopsy before brachytherapy or by frozen sample after enucleation, depending on chosen primary treatment) to help identify patients at high risk for metastases (Weak recommendation).
• Other surgical options, such as local tumor resection, or exenteration, may be considered for tumors not amenable to brachytherapy or enucleation, or as part of palliative care.
• For unresectable tumors not amenable to brachytherapy, consider proton beam radiation therapy (Weak recommendation).
• The preferred treatment of small, thin (< 2-mm thickness) choroidal tumors is controversial. Consider options of observation, brachytherapy, or surgical treatment (Weak recommendation).
• Currently, no systemic adjuvant therapy has been shown to be effective for reducing the risk of metastases in patients with uveal melanoma. Consider clinical trial enrollment for patients at high risk for metastases (visit clinicaltrials.gov for listing of recruiting trials).
• Offer periodic abdominal imaging for detection of hepatic metastasis for all patients after treatment for uveal melanoma (Strong recommendation).