What is Squamous Cell Carcinoma (SCC)?

Squamous cell carcinoma (SCC) is a type of skin cancer characterized by the uncontrolled growth of damaged or mutated squamous cells.


In the U.S., an estimated 700,000 new cases of squamous cell carcinoma are diagnosed every year.

The second most common form of skin cancer, squamous cell carcinoma accounts for 700,000 new cases each year in the US alone. While rarely life-threatening when caught early and treated appropriately, SCC is more dangerous than basal cell carcinoma, a more common form of skin caner—it is estimated that between 4,000 and 8,000 Americans died from squamous cell carcinoma in 2012.

Squamous cell carcinomas are lesions or tumors that form in skin’s squamous cells. SCCs most commonly form on areas of the body that are frequently exposed to the sun over long periods of time, such as the ears, face, scalp, neck, hands, arms and legs, but may also appear anywhere on the body, including mucous membranes, lips, and genitals.

Like all forms of cancer, squamous cell carcinoma is the result of damage to the DNA of the cell that cause them to reproduce rapidly and uncontrollably. If SCCs are left untreated for too long, they may grow into underlying tissue and bone, leading to significant disfigurement. While SCCs rarely spread beyond the skin, it is possible, an event which could become life-threatening.

What are Squamous Cells?


Our skin is made up of several different types of cells, each serving a different role in promoting the healthy functioning of the skin. Skin is composed of two main layers—the epidermis forms the top layer of skin, while the dermis, which contains blood vessels, hair follicles, and the like, form the lower level. Squamous cells make up most of the skin’s top layer.

Accordingly, the word “squamous” comes from the Latin squama meaning “the scale of a fish or serpent.”

Squamous cells are some of the body’s most common. Along with making up the much of the epidermis, they also compose many of passageways of our respiratory and digestive systems. They are often found in the linings of organs.

Signs and Symptoms

What do squamous cell carcinoma look like?

Squamous_cell_carcinoma_(2)Squamous cell carcinomas may appear on patches of the skin regularly exposed to sunlight. They appear as bumps of growths with some common characteristics:

  • Scaly red patches
  • Open sores
  • Raised growths with a divot, dimple, or depression in the center
  • Warts
  • Crusty or bleeding bumps

Squamous cell carcinoma is highly curable when discovered and treated in its early stage. However, SCC can be extremely disfiguring, even deadly, if not treated promptly.

Check regularly for common indicators of sun damage:

  • Wrinkles
  • Changes in skin tone or pigment color
  • New or changing moles
  • Freckles
  • Age spots
  • Skin stiffness
  • Broken blood vessels
  • Causes and Risk Factors

Exposure to UV light, either from the sun or from tanning beds, particularly if is chronic, long-term, and/or result in a blistering sunburn, is believed to be the primary factor in the development of squamous cell carcinoma, although many environmental and genetic factors are likely involved.

Risk Factors and Diagnosis

Many risks factors are associated with squamous cell carcinoma, ranging from hair color and skin tone to family history. Below are some of the characteristics that result in higher risk of developing the cancer:

  • Fair skin
  • Blond hair
  • Light-colored eyes
  • Family history of BCC
  • Previously having BCC, specifically on the nose or scalp

Squamous Cell Carcinoma Treatment

Should one discover that he has SCC, there are many treatment options available, and each option has shown high rates of success. The following treatment options are just a few of the many that exist for SCC:

  • Surgical excision. Excision refers to a surgical procedure that involves numbing the area to be treated with local anesthetic and cutting away the tumor along with a thin margin of normal skin. For SCC, surgical excision is typically a minor, outpatient procedure performed at your dermatologists office.
  • Mohs surgery. Mohs surgery is a common surgical technique for early stage melanoma. During treatment, your doctor (usually a dermatologist), surgically removes one very thin layer of skin at a time at the site of the cancer, checking each layer under a microscope as they go to detect the presence of cancer cells. When they reach a layer with no cancer cells, the surgery is over.
  • Curettage and Electrodessication. Generally performed on smaller lesions, this procedure involves scraping off the tumor with an instrument called a curette, which has with a sharp, ring-shaped tip. After scraping, electricity is used to destroy and remaining cancer cells.
  • Cryosurgery-liquid nitrogen. Liquid nitrogen is applied to the tissue to freeze and destroy the tumor and a small margin of surrounding tissue.
  • Photodynamic therapy (PDT). PDT uses a topical gel and special light to destroy early-stage SCC tumors. A gel is applied to the area of the tumor and given time to sink in. Then, a special light is shined on the area, causing a bio-chemical reaction which kills the cancer cells.
  • Medicated creams. For small, early-stage SCCs, medicated creams may be used to destroy cancer cells. Patients typically pick up the medication at the pharmacy and apply the cream themselves.

Radiation Therapy for Squamous Cell Carcinoma

External beam radiation has been used for decades to treat nonmelanoma skin cancer, including SCC. While less than 1% of cases are treated with radiation currently, a recent body of evidence has verified the effectiveness of the technique with high success rates and low complication rates.

Superficial radiation strategies are especially convenient for patients on blood thinners,  those with complicated lesions around the face, or those with multiple lesions where extensive surgery would be disfiguring or debilitating.

Many times a multi-discipline approach using the skills of the dermatologist, Mohs surgeon, and radiation oncologist can bring about the best customized option for individual patients.

Skip the surgery. Learn more about radiation therapy for nonmelanoma skin cancer.