What is Squamous Cell Carcinoma?
Squamous cell carcinoma is the second most common type of skin cancer, affecting approximately 700,000 Americans each year. It most commonly arises on sun-exposed skin and lips, where cumulative damage from the sun’s harmful ultraviolet radiation is greatest. Individuals at highest risk to develop squamous cell carcinoma typically have a history of frequent sun or tanning bed exposure, previous pre-cancerous lesions, fair hair, light eyes, diminished immune systems or family history of skin cancer. However, squamous cell carcinoma can also develop in response to other carcinogenic stimuli, such as ionizing radiation, chronic inflammation or old wounds, rare chemicals and certain oncogenic viruses.
These cancers can cause extensive local destruction of skin and surrounding tissues, especially when they are large or occur near the nose, ears and eyes. Although unusual, squamous cell carcinoma can even spread (metastasize) to other organ systems and may result in death. The risk of metastasis is greatest when the squamous cell carcinoma is large in size or originates from certain locations such as the lip, nose, ear and mucosal regions. Squamous cell carcinoma accounts for the death of nearly 2,500 Americans each year.
What does squamous cell carcinoma look like?
Squamous cell carcinoma commonly appears as a persistent red scaly growth with overlying crust, or it may look like a warty bump or firm nodule. Occasionally it will present as a non-healing sore or ulceration. Skin cancers frequently bleed and may be tender to the touch. Although they most frequently arise on sun-exposed skin, squamous cell carcinoma may also develop on oral mucosa, genital or peri-anal skin.
Any skin or mucosal lesion which grows, bleeds, changes size or fails to heal should be promptly examined by your provider.
How is squamous carcinoma diagnosed?
During a skin examination, your provider will identify and biopsy any suspicious lesions. The skin sample is sent to a laboratory and processed before very thin slices are cut and placed onto a slide. Our dermatopathologist will look at the slide under a microscope and make a diagnosis. This result is presented to your provider in a final dermatopathology report.
What are the treatment options for squamous cell carcinoma?
Multiple modalities are available for the treatment of squamous cell carcinoma, and your physician will consider your general health in addition to the size, location and subtype of your skin cancer before choosing the best option for you. Many squamous cell carcinomas are surgically removed, either by a simple excision or a more specialized procedure called Mohs micrographic surgery. In some instances, squamous cell carcinoma may undergo liquid nitrogen cryotherapy, radiation therapy, laser removal, photodynamic therapy or treatment with a topical cream or injectable immunotherapy.
What can I expect after a diagnosis of squamous cell carcinoma?
Prompt diagnosis and treatment of squamous cell carcinoma is essential to ensure the best possible outcome. When this cancer is confined to the skin’s uppermost layer (i.e. the epidermis) it is called a squamous cell carcinoma in situ. At this stage, the cancer does not have access to nerves or blood vessels, so it cannot metastasize and cure rates are excellent.
The term squamous cell carcinoma is used when the tumor has invaded the second layer of skin (i.e. the epidermis). When a squamous cell carcinoma is promptly diagnosed and treated, complete cure rates are excellent and removal techniques will result in the best possible outcome. In general, the rate of squamous cell carcinoma spread (or metastasis) ranges from 2 to 10 percent and is dependent on many variables. Even if it is carefully excised a squamous cell carcinoma may recur. So careful follow-up is essential. Furthermore, patients with a history of squamous cell-carcinoma are at increased risk for development of more skin cancers.
How can I protect myself from skin cancer?
The use of an appropriate and frequent broad-spectrum sunscreen, protective clothing and broad-brimmed hats are critical in preventing further damage caused by the sun’s ultraviolet rays. When planning outdoor activities, attempt to avoid peak hours of ultraviolet exposure, which typically occur from 10 a.m. until 3 p.m. Choose a sunscreen with a sun protection factor (SPF) greater than 30, and reapply every two hours and after each water exposure. Seek the shade and be conscious of ultraviolet reflections from water and snow. Do not use indoor tanning facilities. Be sure to perform monthly self-skin examinations and immediately report any suspicious lesions to your dermatologist.