Sebaceous carcinoma is a rare type of cancer that begins in an oil gland in your skin. Sebaceous carcinoma most often affects the eyelids.

Sebaceous carcinoma may begin as a painless lump or thickening of skin on the eyelid. As it grows, the cancer may bleed or ooze. Sebaceous carcinoma that occurs on other parts of the body usually appears as a yellowish lump that may bleed.

Sebaceous carcinoma treatment usually involves surgery to remove the cancer. Sebaceous carcinoma can spread to other areas of the body and may be difficult to treat.

Tests and procedures used to diagnose sebaceous carcinoma include:

• Skin examination. Your doctor will carefully inspect your skin to understand your condition.
• Eye examination. An eye doctor (ophthalmologist) will carefully examine your eyelid and your eye to look for signs that cancer has spread to the tissue (conjunctiva) that covers the inside of your eyelid and the white of your eye (sclera).
• Skin biopsy. Your doctor will remove a small amount of tissue for testing. Specialized laboratory tests can determine if cancer cells are present.

Sebaceous carcinoma treatment typically involves surgery to remove the cancer. Radiation therapy and experimental treatments may be options if you can't undergo surgery.

Treatment is typically led by a doctor who treats skin diseases (dermatologist) who may consult with other experts, such as eye doctors (ophthalmologists) and doctors who use radiation to treat cancer (radiation oncologists). Other experts may be included, depending on your situation.

Treatment options may include:

• Surgery to remove the cancer. Your doctor may recommend a procedure to remove the cancer and some of the healthy tissue that surrounds it (excisional surgery with a normal margin of tissue). A specialist will examine the edges of the tissue to make sure no cancer cells are present. This makes it more likely that all of the cancer cells are removed during surgery.
• Mohs surgery. Mohs surgery is a specialized type of surgery that involves progressively removing thin layers of cancer-containing skin until only cancer-free tissue remains. After each layer of skin is removed, it's examined for signs of cancer. The process continues until there are no signs of cancer. This technique may be helpful if your cancer is located in a spot that makes taking a wide margin of healthy tissue difficult, such as on your eyelid or on your face.
• Radiation therapy. Radiation therapy uses powerful energy beams, such as X-rays and protons, to kill cancer cells. For sebaceous carcinoma, radiation therapy may be used alone, or it can be used after surgery to kill any cancer cells that might remain.
• Clinical trials. Clinical trials to test new treatments may be an option. Ask your doctor whether you're eligible to participate in a clinical trial.