There are many nonmelanoma skin cancer types, the two most common being basal cell carcinoma and squamous cell carcinoma, which are named after the cells that become cancerous. Basal cell carcinomas originate in the round cells in the lower layer of the epidermis, and squamous cell carcinomas develop in the flat cells that make up most of the epidermis.
Basal cell carcinoma accounts for around 80 percent of skin cancer cases. It usually develops in places that have been exposed to the sun, such as the face and neck. Squamous cell carcinoma makes up roughly the other 20 percent of all cases of skin cancer. Like basal cell carcinoma, this skin cancer usually appears on areas of the body that have been exposed to the sun; however, squamous cell carcinoma can also develop on the lips, mucous membranes (like the skin that lines the mouth or nose) or parts of the body where patients have experienced chronic inflammatory skin conditions. Both of these types of skin cancer typically develop slowly and rarely metastasize (spread to other areas), although squamous cell carcinoma is more likely to spread than basal cell carcinoma.
A small percentage of skin cancer cases are categorized as rarer types of nonmelanoma skin cancer, which include:
- Merkel cell carcinoma – This type of cancer develops in the hormone-producing cells of the skin and hair follicles. It gets its name due to its resemblance to normal Merkel cells of the skin under a microscope. This skin cancer can appear as a firm lesion on the skin. These lesions can appear in various sizes and are typically red, blue or skin-colored.
- Cutaneous lymphoma – The word “cutaneous” simply refers to the skin. Some of the body’s lymphocytes (immune cells) are found in the skin, so when the cancer originates there, it is called cutaneous lymphoma. Depending on the type of lymphocytes affected (B cells or T cells), this type of skin cancer may be classified as cutaneous B-cell lymphoma or cutaneous T-cell lymphoma. The skin lesion often looks red and scaly, similar to eczema.
- Skin adnexal neoplasm – These tumors originate in the hair follicles or skin glands. Most often, these tumors are benign, although it is possible for them to be malignant and to metastasize.
- Cutaneous sarcoma – Sarcomas are rare tumors that can occur in almost any soft tissues of the body, including the skin. They may appear as a lump under the skin and are usually painless.
- Dermatofibrosarcoma protuberans (DFSP) – This is a rare type of sarcoma that develops in the deep layers of the skin. While DFSP is most commonly found on the torso, it can also be found on the arms, head, neck or legs. It usually looks like a flat or slightly raised skin patch that feels rubbery or hard, and is typically violet, reddish brown or skin colored.
The Cutaneous Oncology Program at Moffitt Cancer Center offers multispecialty treatment for all types of skin cancer in one convenient location. No matter what point you are at in your journey, you will be welcome here at Moffitt, with or without a referral. Call us today at 1-888-663-3488, or complete a new patient registration form to set up an appointment.