In general, tumors are either benign (not cancerous) or malignant (cancerous). They may occur in different parts of the eye and cause varying visual effects depending on the specific location involved. Intraocular tumors may be found on a routine eye exam, or may cause vision problems prompting those affected to seek care. Frequently patients are referred to a Colorado Retina specialist to determine if suspicious ocular lesions should be observed or treated. Once a patient is referred over, our tumor service is designed to help patients schedule appropriately for prompt evaluations. The initial clinic visits usually require several hours as baseline imaging studies are needed and a clinical exam with a physician is performed. For most, a specific diagnosis is quickly established, and a plan for follow-up is developed.
A newly identified intraocular tumor(or lesion) causes anxiety for many patients. By definition intraocular lesions are found inside the eye, and usually are not visible without special eye exams. Some intraocular lesions may be found on a routine eye exam even in patients without vision symptoms. Some intraocular lesions may cause visual disturbances depending on the specific location within the eye and relation to intraocular structures.
Malignant tumors are associated with cancer and can affect the whole body. For some, the malignant tumor of the eye may be the first sign of systemic cancer. Malignant tumors may start in the eye, such as ocular melanoma. Other malignant tumors are metastases, which have spread to the eye from cancer in another part of the body, such as breast, lung, GI tract, prostate or other sources. Lymphoma may also evolve within the eye.
Benign tumors are not harmful to one's health, and may be observed when not affecting vision. Regular observation is recommended as some benign conditions may undergo “neoplastic transformation” to become malignant. Some types of benign tumors may be associated with systemic conditions and further testing may be needed. Examples of benign tumors include nevus, osteoma, hemangioma, congenital hypertrophy of the retinal pigment epithelium (CHRPE), and others. Benign tumors of the eye are important to accurately diagnose and measure as they are sometimes associated with other types of medical conditions. It is rare for these lesions to have the potential to turn into cancer.
TYPES OF BENIGN TUMORS / LESIONS
1. Choroidal nevus - is a focal growth of melanocytes in the choroid. A wide variety of nevi exist, with differences in size, shape, and color. Baseline examinations are used as references for future exams. A choroidal nevus is usually stable on serial exams; any changes in size or appearance may signal“neoplastic transformation” into a melanoma.
2. Congenital Hypertrophy of the Retinal Pigment Epithelium (CHRPE) is a benign condition thought to be present at birth, although usually detected in childhood or young adulthood. These have a characteristic appearance and are usually located non-centrally with little if any effect on vision. Extremely rare conversion to RPE adenocarcinoma has been described.
3. Choroidal hemangioma is a vascular lesion of abnormal tissue in the choroid. Depending on the location and propensity to accumulate sub-retinal fluid, choroidal hemangiomas may cause vision disturbances. A specialized form of laser-activated dye treatment known as Photodynamic therapy (PDT) may be effective in improving vision. Choroidal hemangiomas which are growing may respond to radiation treatment (either external radiation or plaque brachytherapy). Choroidal hemangiomas can be associated with Sturge-Weber Syndrome.
4. Choroidal osteoma is an abnormality of the choroid in which localized calcium deposition disrupts the retinal function. Sub-retinal neovascularization may occur and treatment can be useful in preserving vision.
5. Melanocytoma is a pigmented lesion usually found on the optic nerve head. It does not grow, although the appearance may change during a normal posterior vitreous detachment (PVD), and should be monitored during this occurrence. Neoplastic transformation into melanoma is rare.
6. Astrocytic Hamartoma is usually found in children and has a characteristic appearance, which distinguishes it from malignancies.
7. Vasoproliferative tumors, Coats disease, and eccentric disciform (PEHCR) are vascular lesions that can appear as growths in the retina or choroid. Exams should be performed to exclude the diagnosis of Von-Hippel Lindau syndrome which is associated with systemic malignancies. Proper diagnosis of these lesions allows for appropriate therapy when needed.
INTRAOCULAR TUMORS / OCULAR CANCERS
1. Choroidal melanoma is the most common primary cancer occurring in the adult eye. Choroidal melanoma is diagnosed by the characteristic features observed with multimodal imaging and clinic exam. Choroidal, ciliary body, and iris melanoma are the three forms of intraocular melanoma, and are known collectively as uveal melanoma. The term “ocular melanoma” is the most broad as it includes uveal and conjunctival melanoma. All ocular melanomas may be able to spread to other parts of the body, a manifestation known as metastasis. Uveal melanoma metastasis typically involves the liver. Genetic mutations within the melanoma cells determine the ability to metastasize. The genetic evaluation of melanomas by fine needle aspirate biopsy (FNAB) has become an international standard of care.
2. Choroidal metastasis Cancers originating in other tissues of the body(e.g. breast, lung, GI tract, prostate or other sources) may metastasize to the eye. Though many parts of the eye may be affected, usually the choroid is involved. The choroidal metastasis will commonly cause vision problems due to mass effects and fluid accumulations in the sub-retinal space. Treatment is coordinated with oncologists and designed to eliminate the tumor in the eye while preserving or improving the vision. In some cases a biopsy of the eye is important for diagnosis or treatment.
3. Lymphoma may also involve the eye structures and frequently will need specialized biopsies for diagnosis. Primary intraocular lymphoma (PIOL) commonly found in the vitreous is associated with central nervous system (CNS) lymphoma. Choroidal lymphoma may have amore benign course.
