Introduction:
Squamous cell carcinoma is a type of skin cancer that develops in the squamous cells, which are thin and flat cells that make up the outermost layer of the skin (epidermis). All places in the body that contain squamous cells can get affected by this cancer. It is the second most common type of skin cancer, is relatively slow-growing, and does not usually result in fatal complications if treated in early stages. Prolonged sun or UV radiation exposure (tanning beds or lamps) is the most common cause of this type of skin cancer.
What Are the Symptoms of Squamous Cell Carcinoma?
Squamous cell carcinoma commonly affects the scalp, face, ears, lips, and hands, as these places are most often exposed to sun rays. But it can also develop inside the mouth, genitals, and feet. The signs and symptoms of SCC are:
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Red and firm nodules on the affected area.
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Open sore with a scaly crust.
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Rough and scaly patch on the skin that develops into an open sore.
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An old scar gets a raised area.
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Wart-like growth on the anus or genitals.
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A red rough patch inside the mouth.
Consult a doctor immediately if one notices a skin sore or lesion that does not heal even after two months.
What Are the Causes of Squamous Cell Carcinoma?
When the squamous cells present in the epidermis undergo DNA mutations, they multiply uncontrollably and form SCC. The DNA contains information and instructions for the cell. But when they get mutated, these cells start growing out of control and form abnormal cancer cells. These cancer cells do not die like normal skin cells.
This DNA mutation is caused by exposure to ultraviolet radiation. Ultraviolet radiation is found in sun rays and commercial tanning lamps and beds. But this theory does not support skin cancers that develop in places hardly exposed to the sun. So it is right to believe that other factors also contribute to the development of SCC. The risk factors that appear to increase the incidence of squamous cell carcinoma are:
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It is most common in elderly people (more than 64years of age).
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Males are more commonly affected than females.
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People who have blond or red hair are more susceptible.
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The same goes for people with blue, green, or grey eyes.
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Although anyone can get SCC, fair-skinned individuals are more susceptible. This is because they have less melanin in the skin, which are the pigments that protect the skin from the harmful radiation of the sun.
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People who get sunburnt easily or have freckles.
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People who tan their skin using indoor tanning beds.
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Spending the majority of the day under the sun without proper protective clothing.
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Individuals with immunocompromised conditions, such as leukemia, lymphoma, AIDS, etc.
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Organ transplant patients who take immunosuppressants.
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The presence of precancerous skin conditions, such as actinic keratosis or Bowen's disease.
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Exposure to chemicals like arsenic.
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A history of skin cancer.
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Rare genetic conditions like xeroderma pigmentosum, which results in extreme sensitivity to sunlight.
How Is Squamous Cell Carcinoma Diagnosed?
The doctor will examine the skin lesion and note its size, shape, color, and texture. The doctor will also check the lymph nodes and other body parts for a similar skin lesion. They will take a detailed medical history to understand if one has any risk factors for SCC or other skin cancer.
If the doctor suspects it to be SCC, then a biopsy or sample of the affected skin is taken and sent for lab testing. The presence of cancerous or abnormal squamous cells are detected under the microscope in the lab. There are four types of skin biopsy, which are:
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Shave Biopsy - The doctor will shave the top layer of your skin (dermis) using a sharp blade.
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Punch Biopsy - Here, a sharp and hollow surgical tool is used to punch out a circle of skin.
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Incisional Biopsy - Part of the skin lesion is removed using a scalpel.
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Excisional Biopsy - The entire skin lesion along with some surrounding tissue is cut using a scalpel.
If needed, the doctor might also suggest getting the following imaging tests like X-rays, CT scans, MRI scans, and positron emission tomography (PET) scans to see if the cancer has metastasized or spread.
How Is Squamous Cell Carcinoma Treated?
Treatment and prognosis of SCC depend on its extent and severity, patient’s overall health, and its location. The prognosis is excellent if detected and treated early. The treatment options include:
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Mohs’ Micrographic Surgery - The doctor removes the abnormal skin along with some of the surrounding tissue using a scalpel. The cutout skin is examined under the microscope for cancer cells. If cancer cells are present, then the procedure is repeated until the sample is free of cancer cells.
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Excisional Surgery - Here, the surgeon removes cancer cells along with a thin layer of surrounding healthy skin. Then the wound is closed with stitches.
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Electrosurgery - Otherwise called curettage or electrodesiccation, it is the method where the lesion is scraped and the surrounding skin is burned off to kill cancer cells.
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Cryosurgery - Here, liquid nitrogen is used to freeze and destroy cancer cells.
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Radiation Therapy - High-energy X-rays are used to kill cancer cells.
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Photodynamic Therapy (PDT) - A photosensitizing substance is applied to the cancerous areas, after which the area is exposed to strong light for a few minutes.
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Laser Surgery - Laser is used to remove skin cancer.
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Topical Medicines - 5-fluorouracil and Imiquimod.
What Are the Complications of Squamous Cell Carcinoma?
With prompt diagnosis and treatment, SCC can be cured without any complications. But in some aggressive type, cancer cells can migrate to other organs and lymph nodes, which can be fatal.
SCC usually is aggressive if it involves a larger or deeper skin area, if the mucous membrane is involved (like the lips), or if the patient has a week immune system.
Preventive Measures:
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Try to follow the following tips to reduce the risk of SCC:
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Avoid going out in the sun between 10 a.m. and 3 p.m.
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Use sunscreen of at least 30 SPF every day, even during winters.
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Wear clothes that cover the hands and legs, and hats to protect the face and head while going out in the sun.
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Do not use tanning beds.
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Check the body regularly for abnormal skin growths or lesions.
Conclusion:
Squamous cell carcinoma is a commonly occurring skin cancer that occurs due to alterations in the DNA of squamous cells which results in uncontrolled proliferation of these cells. Usually, the parts of the skin exposed to sunlight frequently like the face, arms, or neck are affected. If left untreated, this cancer can affect a large part of the skin and can also spread to other body parts, such as tissues, bones, and lymph nodes. When this happens, it can cause severe complications. The skin in the face, neck, chest, back, lips, hands, and legs are more susceptible to sun exposure. SCC results in scaly and red patches or open sores on the skin. The other factors that increase the risk of one getting SCC are old age, fair skin, exposure to chemicals like arsenic, and changes in the DNA of squamous cells. It is most common in males and elderly people (more than 64 years). If one notices any of the signs and symptoms of SCC mentioned above, a physician should be consulted immediately.