Understanding Squamous Cell Carcinoma: Causes, Symptoms, and Treatment
Squamous Cell Carcinoma (SCC) is one of the most common types of skin cancer. While it can occur on any part of the body, it typically develops in areas that receive significant sun exposure, such as the face, ears, neck, scalp, arms, and hands. Like other skin cancers, SCC develops when skin cells begin to grow abnormally and uncontrollably. In this article, we will explore the causes, symptoms, diagnosis, staging, and treatment of SCC to help you understand this condition better.
What is Squamous Cell Carcinoma?
Definition and Overview
Squamous Cell Carcinoma (SCC) is a type of skin cancer that starts in the thin, flat cells that make up the outer layer of the skin, known as the epidermis. These cells are called squamous cells. When SCC develops, the squamous cells grow uncontrollably and form a malignant tumor. If left untreated, the cancer can spread (metastasize) to other parts of the body through the lymphatic system or bloodstream, leading to life-threatening complications.
SCC is the second most common type of skin cancer, accounting for about 20% of all cases. It usually appears as a red, scaly patch or sore that does not heal, or as a raised growth with a central depression.
Types of Squamous Cell Carcinoma
There are different types of SCC, including:
- Cutaneous Squamous Cell Carcinoma: This type of SCC occurs on the skin and is the most common form of the cancer. It is usually caused by long-term exposure to the sun’s harmful UV rays, but can also be caused by exposure to artificial sources of UV radiation, such as tanning beds.
- Mucosal Squamous Cell Carcinoma: This type of SCC occurs in the moist tissues that line the body’s cavities, such as the mouth, throat, genitals, and anus. It is often associated with the human papillomavirus (HPV) infection.
- Cutaneous Horn: This type of SCC appears as a hard, conical projection on the skin’s surface and is usually caused by long-term sun exposure or chronic inflammation. It is named for its resemblance to a horn.
Prevalence and Risk Factors
SCC is more common in people with fair skin, light-colored hair and eyes, and those who have a history of excessive sun exposure or sunburns. Other risk factors include:
- Age: SCC is more prevalent in older adults, particularly those over 50 years of age. However, it can occur in younger people as well.
- Gender: Men are more likely to develop SCC than women.
- Immunosuppression: People with weakened immune systems due to medical conditions (e.g., HIV/AIDS) or medications (e.g., chemotherapy, immunosuppressants) are more prone to SCC.
- Occupational Exposure: Certain jobs that involve prolonged exposure to UV radiation, such as construction workers, farmers, and outdoor athletes, increase the risk of SCC. Additionally, exposure to certain chemicals, such as arsenic, can also increase the risk.
It is important to protect your skin from the sun’s harmful UV rays to reduce your risk of developing SCC. This can be done by wearing protective clothing, using sunscreen with an SPF of at least 30, seeking shade during peak sun hours, and avoiding tanning beds.
Causes of Squamous Cell Carcinoma
Squamous cell carcinoma (SCC) is a type of skin cancer that develops in the squamous cells that make up the outer layer of the skin. While SCC can occur in any part of the body, it is most commonly found on sun-exposed areas such as the face, neck, arms, and hands. In this article, we will explore the various causes of SCC in more detail.
Ultraviolet (UV) Radiation Exposure
The primary cause of SCC is exposure to UV radiation from the sun or tanning beds. Over time, repeated exposure to UV radiation damages the DNA in skin cells, causing mutations that lead to cancer. The risk of SCC increases with the intensity and duration of sun exposure, as well as the frequency of sunburns. People who work outdoors or spend a lot of time in the sun are at a higher risk of developing SCC.
It is important to note that UV radiation can also penetrate through clouds and windows, so even on cloudy or cool days, it is important to protect your skin from the sun’s harmful rays. Wearing protective clothing, such as long-sleeved shirts and wide-brimmed hats, and using sunscreen with a high SPF can help reduce your risk of developing SCC.
Human Papillomavirus (HPV) Infection
HPV is a common sexually transmitted infection that can lead to genital warts and cervical cancer. Certain strains of HPV are also associated with SCC of the skin, particularly in immunocompromised individuals. In addition to practicing safe sex, getting vaccinated against HPV can help reduce your risk of developing SCC and other HPV-related cancers.
Smoking and Tobacco Use
Smoking and tobacco use increase the risk of SCC, particularly in areas of the body that are not typically exposed to the sun, such as the lungs, mouth, throat, and esophagus. Tobacco smoke contains carcinogens that damage cells and increase the risk of cancer. Quitting smoking and avoiding tobacco use can help reduce your risk of developing SCC and other types of cancer.
Chronic Skin Inflammation and Injury
Chronic skin inflammation and injury, such as from burns, scars, and chronic wounds, increase the risk of SCC. Inflammation causes cells to divide more rapidly, increasing the likelihood of DNA damage and cancer formation. It is important to properly care for any skin injuries and seek medical attention if they become infected or do not heal properly.
Genetic Factors and Family History
Some inherited genetic mutations, such as those associated with xeroderma pigmentosum, increase the risk of SCC. If a family member has had SCC, the risk of developing the cancer is also increased. It is important to discuss any family history of cancer with your healthcare provider and undergo regular skin cancer screenings to detect any potential issues early on.
While SCC can be a serious and potentially life-threatening condition, there are steps you can take to reduce your risk of developing the cancer. By protecting your skin from the sun, practicing safe sex and getting vaccinated against HPV, avoiding tobacco use, properly caring for skin injuries, and discussing any family history of cancer with your healthcare provider, you can help keep your skin healthy and reduce your risk of SCC.
Recognizing the Symptoms
Early Signs and Symptoms
SCC typically starts as a small, firm, red bump on the skin that may be painful to the touch. Over time, the bump may grow and become scaly or crusty. Other early signs and symptoms may include:
- A persistent sore or ulcer that does not heal
- A raised, rough patch of skin that may feel like sandpaper
- A wart-like growth that may bleed or crust
Progression and Advanced Symptoms
If left untreated, SCC can grow larger, deeper, and spread to other parts of the body. Advanced symptoms may include:
- A hard, dome-shaped bump on the skin with a central depression or ulceration
- A large, irregularly shaped growth with multiple colors and uneven borders
- An open sore that bleeds, crusts, or oozes
- A scaly patch that may itch or burn
- A swollen lymph node that may be tender or hard to the touch
If SCC is left untreated, it may lead to serious complications, such as:
- Invasion of nearby tissues and organs, such as the bones, muscles, and nerves
- Destruction of the skin’s underlying structures, such as cartilage and bone
- Nerve damage and loss of sensation in affected areas
- Disfigurement and scarring
- The spread of cancer to other parts of the body, such as the lymph nodes, lungs, liver, and brain
Diagnosis and Staging
Your doctor will perform a physical examination of the affected skin to look for signs of cancer. They may use a special magnifying instrument (dermatoscope) to get a closer look at the skin.
If SCC is suspected, your doctor may perform a biopsy to remove a small sample of the skin for examination under a microscope. There are different types of biopsies, including:
- Shave biopsy: A thin, flat layer of skin is removed with a scalpel.
- Punch biopsy: A small, round piece of skin is removed with a special tool.
- Incisional biopsy: A small section of the tumor is removed with a scalpel.
- Excisional biopsy: The entire tumor is removed with a scalpel.
If SCC is advanced, your doctor may order imaging tests, such as X-rays, CT scans, or MRI scans, to determine if the cancer has spread to other parts of the body.
Staging System for Squamous Cell Carcinoma
Once SCC is confirmed, your doctor will use a staging system to determine how advanced the cancer is and guide treatment decisions. The staging system takes into account the size of the tumor, whether it has spread to nearby lymph nodes or other organs, and whether the cancer has metastasized. The stages range from Stage 0 (in situ) to Stage IV (metastatic).
The treatment options for SCC depend on the size, location, and stage of the cancer, as well as your overall health and preferences. The main treatment options include:
- Surgical Excision: The cancer is removed with a scalpel, usually under local anesthesia.
- Mohs Surgery: A specialized surgical technique that removes thin layers of skin progressively until all cancer cells are eliminated.
- Radiation Therapy: High-energy radiation is used to kill cancer cells. It is typically recommended for SCC that is either too large to be treated with surgery or in areas where surgery is not feasible.
- Topical Medications: Certain creams or gels may be used to treat SCC in the early stages.
- Combination Therapy: A combination of surgery, radiation, and/or chemotherapy may be recommended for advanced SCC or high-risk cases.
SCC can also be prevented by practicing good sun safety measures, such as wearing protective clothing, using broad-spectrum sunscreen with an SPF of 30 or higher, seeking shade during peak sun hours, and avoiding tanning beds. Early detection and treatment also play a crucial role in the successful management of SCC.