Overview of Skin Cancer of the Eyelids
Skin cancer, the most common type of malignancy, can develop on any area of the skin exposed to the sun, including the eyelids. In most cases, lesions occur on the lower lids, but they can occur anywhere on the eyelids, in the corners of the eye, under the eyebrows, and in adjacent areas of the face.
Basal cell carcinoma is the most common type, accounting for 90% of cases. Other eyelid cancers include squamous cell carcinoma, sebaceous gland carcinoma, and malignant melanoma. Together, these account for 10% of eyelid malignancies.
Basal cell carcinoma
Approximately 75% of cases of basal cell carcinoma of the eyelid occur on the lower lid. The lesion usually develops as a small, firm, painless nodule with a smooth, pearly appearance and may develop telangiectasia (a reddish hue caused by dilated capillaries).
Basal cell carcinoma of the eyelid progresses very slowly. Metastasis is rare, but if left untreated, the disease can spread to and destroy surrounding tissue. Complete recovery is possible with surgical excision, but basal cell carcinoma can recur.
Squamous cell carcinoma
Squamous cell cancer usually occurs on the lower lid. The lesion is usually a raised, scaly patch of reddened skin. It may resemble a scab that does not heal. As the disease progresses, the lesion may bleed or drain pus. Metastasis is rare, but it can invade local tissue and metastasize.
Malignant melanoma originates in melanocytes, skin cells that produce melanin, the pigment responsible for variations in skin color. There are several different types of melanoma and they vary in appearance. Two types commonly occur on the eyelids. Lentigo maligna melanoma (LMM) lesions are flat and tan with irregular borders and become increasingly mottled as they grow. Nodular melanoma (NM) lesions are slightly elevated, blue-black, and resemble blood blisters.
Lentigo maligna melanoma spreads slowly, remains in superficial layers of skin, and does not metastasize. Nodular melanoma is the most aggressive type of melanoma. It grows rapidly and is often fully invasive when diagnosed. It also has a higher rate of systemic metastasis than basal cell and squamous cell carcinomas.
Sebaceous gland carcinoma
This rare cancer primarily affects the meibomian glands of the eyelids and to a lesser extent the Zeiss glands, which produce the oily layer of the tear film. These tumors most commonly occur in the upper eyelid and are usually firm and painless, often with a yellow tinge. Sebaceous gland carcinomas are highly aggressive and frequently metastasize. They are often mistaken for a benign condition, such as chronic blepharitis or a chronic chalazion (nodule formed by inflammation of the meibomian gland). This delay in diagnosis can result in metastasis to the orbit (bony socket surrounding the eye) or to the lymph nodes.
Incidence and Prevalence
In the United States, malignant tumors of the eyelid occur most often in older Caucasians with a history of prolonged sun exposure. Basal cell carcinoma is the most common eyelid malignancy. Squamous cell carcinoma accounts for 5% of eyelid malignancies. Malignant melanoma of the eyelid is rare, accounting for 1% of eyelid skin cancers. Sebaceous gland carcinoma accounts for 0.8% of eyelid tumors. Lentigo maligna melanoma is the least common and typically occurs in people over 70.
The primary risk factor for eyelid cancer, with the exception of sebaceous gland carcinoma, is excessive exposure to sunlight. Older people are affected more often because they have had more exposure to the sun's UV rays. Women over age 60 and younger people who have had radiation therapy to the face have the highest risk for sebaceous gland carcinoma. Eyelid cancer is prevalent among people of European descent with fair skin because their skin provides little natural protection against the sun. Hereditary risk factors also may be involved.