What Is Iris Melanoma?

Iris melanoma is a cancer of the eye. Originating with the erratic production of cells responsible for iris color, known as melanocytes, iris melanoma is often regarded as an asymptomatic condition, meaning an individual will usually not exhibit any signs or symptoms of illness. Once detected, treatment for iris melanoma, also known as ocular melanoma, is determined by the severity and position of the tumor. If left untreated, an ocular melanoma can contribute to secondary conditions that may range from glaucoma to blindness.

Most iris melanomas are detected during routine eye examinations. Using focused light, an ophthalmologist examines the inner workings of the eye, which can reveal signs indicative of an iris melanoma, including blood vessel distention and pupil distortion. Upon discovery, angiographic and ultrasound testing may be performed to evaluate the tumor and health of the surrounding ocular blood vessels. It is not uncommon for a sample of the growth to be obtained for laboratory testing to discount or confirm malignancy.

Similar to other forms of malignancy, it is unknown what initiates the abnormal cell production associated with an iris melanoma. Death is a part of normal cellular life cycles, but mutated melanocyte cells do not die. The accumulation of mutated melanocytes contributes to the formation of a neoplastic, or tumorous, mass in the middle portion of the eye, known as the uvea. As the tumor matures, eye function becomes jeopardized. Although most individuals with an eye melanoma remain asymptomatic, it is possible for signs and symptoms to sometimes present.

Symptomatic individuals may notice changes in their iris’ appearance, such as the shape of their pupil and localized darkening. Vision changes, including persistent blurriness or sensitivity to light, may also occur. If a malignant iris melanoma remains undiagnosed, or if treatment is delayed, the individual may be at significant risk for vision loss or metastasis, which is the spread of malignancy to other parts of the body.

Treatment for an iris melanoma is determined by several factors, including the staging and location of the tumor. If the tumor is deemed benign, or noncancerous, and is not impairing eye function or one’s vision, it may only require regular monitoring. Malignant iris melanomas, also known as iris neoplasias, may necessitate surgical removal of the tumor and the administration of cryo- and radiation therapies.

The excision of an iris melanoma can require the partial or complete removal of the iris. Significantly invasive tumors can necessitate enucleation, or eye removal, and the implantation of a prosthetic eye. Postoperative therapy may involve the direct administration of cryo- and radiation therapies to the affected eye to eliminate cancerous cells that may remain.