Squamous Cell Carcinoma
What is Squamous Cell Carcinoma?
Squamous cell carcinoma (SCC) is one of the most common forms of skin cancer and it originates from squamous cells, which are flat cells located on the outermost layer of the skin, the epidermis. As it progresses, SCC often presents as a firm, red nodule or a flat sore with a scaly crust. These lesions may also resemble open sores, warts, or elevated growths with a central depression. As for color, SCCs can range from a reddish patch to a flesh-colored lesion, though they might occasionally appear darker.
The location of SCC can vary, but it predominantly develops on areas of the skin with prolonged exposure to the sun. This includes the face, ears, neck, lips, back of the hands and forearms. However, it’s worth noting that SCC can also appear in areas that have not been exposed to the sun, such as the legs or inside the mouth, especially in individuals with certain risk factors.
In terms of its prevalence, SCC is the second most common form of skin cancer after basal cell carcinoma. Every year, millions of cases are diagnosed worldwide, with an increasing incidence likely due to factors like prolonged sun exposure and an aging population. It’s crucial to recognize and treat SCC early, as it can become invasive, leading to tissue damage and, in rare cases, metastases to distant organs. Regular skin checks and sun protection are vital preventive measures against this malignancy.
Types of SCC
SCC is not a one-size-fits-all diagnosis, as it manifests in several types, each with distinct characteristics. The in situ form, also known as Bowen’s disease, is the earliest stage. It’s confined to the outer skin layer and presents as red, scaly patches. Invasive SCC is the most common form, where cancer cells break through the epidermis and invade deeper tissues.
This category includes keratoacanthoma-type SCCs, which are dome-shaped tumors that can grow rapidly, but might also regress spontaneously. Verrucous carcinoma, another subtype, is a wart-like growth that’s slower to develop and less likely to metastasize. It’s important to recognize the varying types of SCC because treatment approaches and prognosis can differ. While some types are more aggressive than others, early detection and appropriate treatment are key to preventing complications and ensuring favorable outcomes.
Symptoms of SCC
Recognizing the symptoms of SCC is crucial for early detection and effective treatment. While the appearance of SCC can vary, certain signs raise suspicion:
- Persistent, scaly red patches: These might bleed or crust over and are often accompanied by discomfort or itchiness.
- Growing nodules: They can be firm to the touch, raised from the skin’s surface, with some even resembling a wart.
- Open sores: These can linger for weeks and even months. They might heal and then reopen, suggesting an underlying issue.
- Sudden soreness or a raised area on a pre-existing scar or ulcer: Especially in areas previously subjected to burns, radiation, ulcers, or long-standing injuries.
- Rough or scaly patches on the lips: These might evolve into more severe lesions or open sores, indicating a variant of SCC known as lip cancer.
- Unexplained pain in an area: While not always an evident sign on visual inspection, pain or discomfort in a specific skin region can be indicative of SCC.
Given the broad spectrum of these symptoms, any unusual or persistent skin changes should be promptly evaluated by a dermatologist.
Causes of SCC
The development of SCC is often a culmination of various factors, with the primary cause being prolonged exposure to ultraviolet (UV) radiation. Here’s a rundown of the leading causes:
- Sunlight: UV rays from the sun are a major culprit. Areas of the skin frequently exposed to sunlight, such as the face, neck, and hands, are at increased risk.
- Tanning Beds: These machines emit UV rays, which can accelerate skin damage, making users more susceptible to SCC.
- HPV (human papillomavirus): Certain strains of HPV have been linked to SCC, especially those that affect the genital regions.
- Chemical Exposure: Regular contact with certain chemicals, like arsenic or tar, can increase the risk.
- Immunosuppression: Individuals with weakened immune systems, either from conditions like HIV or medications for organ transplants, are at increased risk.
- Chronic Inflammation and Scarring: Long-standing skin injuries or areas of chronic inflammation can, over time, develop into SCC.
- Actinic Keratosis: These precancerous skin lesions, caused by sun damage, can evolve into SCC if left untreated.
Understanding these causes underpins the importance of preventative measures and regular skin checks.
Risk Factors of SCC
SCC is influenced not just by direct causes, but also by a range of risk factors that can increase an individual’s vulnerability to developing this form of skin cancer. Recognizing these risk factors aids in better understanding one’s own likelihood and in adopting preventive strategies.
- Age and Gender: While anyone can develop SCC, it’s more frequently diagnosed in individuals over the age of 50. Men are often more susceptible than women, possibly due to greater lifetime sun exposure or differences in skin protection habits.
- Complexion: People with fair skin, especially those with blonde or red hair and blue or green eyes, are at a higher risk. The decreased melanin in lighter skin provides less protection from harmful UV rays.
- Geographical Location: Residing in areas with high altitudes or where sunlight is strong year-round increases the exposure to UV rays. As such, individuals living closer to the equator or in sunny climates often have a heightened risk.
- History of Sunburns: Individuals who’ve had severe or multiple sunburns during their lifetime, especially in childhood, face a higher risk. Each sunburn episode can cause cumulative damage to skin cells.
- Previous Radiation Treatment: Patients who have undergone radiation therapy for other health conditions have an increased likelihood of developing SCC in the irradiated areas.
- Family History: While the familial link isn’t as strong as in some other cancers, having a close relative with SCC can slightly increase one’s risk, suggesting a potential genetic predisposition.
- Smoking: Tobacco use, especially smoking, has been linked to an increased risk of SCC, particularly on the lips. The harmful chemicals in tobacco can lead to cellular changes in the mouth, making it more vulnerable to cancerous transformations.
- Exposure to Certain Chemicals: Beyond the chemicals directly implicated as causes, prolonged exposure to polycyclic aromatic hydrocarbons (found in coal and tar) can be a risk factor, even if they don’t directly induce squamous cell carcinoma.
- Genetic Disorders: Certain rare genetic disorders, such as xeroderma pigmentosum, make individuals highly sensitive to sunlight, leading to a dramatically increased risk of skin cancers, including SCC.
- Existing Skin Conditions: Diseases like albinism and epidermolysis bullosa can make the skin more susceptible to damage and, consequently, to cancers like SCC.
- History of Skin Cancer: Individuals who’ve previously been diagnosed with any form of skin cancer, be it SCC, basal cell carcinoma or melanoma, are at increased risk of developing SCC in the future.
- Immunosuppressive Drugs: These drugs, often used post organ transplant to prevent the body from rejecting the new organ, suppress the immune system, reducing its ability to fight off cancers. As a result, transplant recipients can have a much higher risk of SCC.
- Human Immunodeficiency Virus (HIV): While also a cause, it’s worth noting as a risk factor since individuals with HIV have a compromised immune system, making it harder for their bodies to stave off cancers like SCC.
- Psoralen and Ultraviolet A (PUVA) Therapy: The treatment, used primarily for psoriasis, involves taking a drug that makes the skin more sensitive to light and then exposing the skin to UVA rays. Repeated treatments can increase the risk of SCC.
While some risk factors, such as age, genetics, or complexion, are beyond our control, others can be mitigated through informed lifestyle choices. Awareness of these risk factors is the first step toward proactive monitoring and prevention. Regular dermatological check-ups, especially for those with multiple risk factors, are invaluable for early detection and effective management of SCC.
SCC typically begins with a visual examination of the skin. If a lesion or growth appears suspicious, further diagnostic steps are taken:
- Physical Examination: A dermatologist will first assess the size, shape, color, and texture of the lesion. They’ll also ask about how long it has been present, any changes in its appearance, and if there are other similar lesions on the body.
- Biopsy: To confirm SCC, a biopsy is essential. A small sample of the suspicious tissue is removed and sent to a laboratory. Pathologists then examine the sample under a microscope to identify cancerous cells.
If SCC is confirmed, additional tests may be required to determine the cancer’s stage. This could include imaging tests or sentinel lymph node biopsies to check if the cancer has spread. Prompt and accurate diagnosis is crucial for effective treatment and favorable outcomes in SCC cases.
Understanding the stages of squamous cell carcinoma (SCC) is crucial for both prognosis and treatment. SCC staging is determined by factors such as tumor size, depth of invasion and whether it has spread to nearby lymph nodes or other parts of the body.
- SCC Stage 0: Also known as in situ or Bowen’s disease, this is the earliest stage of SCC. The cancer cells are confined to the epidermis and haven’t penetrated deeper layers. It typically appears as red, scaly patches on the skin.
- SCC Stage 1: In this stage, the tumor has grown larger but remains localized, with no spread to nearby lymph nodes. The cancer may have penetrated the dermis but is no larger than 2 centimeters across.
- SCC Stage 2: At this stage, the tumor might be larger than 2 centimeters, or it has certain high-risk features like a deeper invasion into the skin, yet it still hasn’t spread to nearby lymph nodes or distant parts.
- SCC Stage 3: Cancer has progressed into the facial bones or one nearby lymph node, but it hasn’t affected other parts of the body. The affected lymph node remains smaller than 3 centimeters.
- SCC Stage 4: This is the most advanced stage. The cancer has either spread to other parts of the body, involves more than one lymph node, or has affected a lymph node larger than 3 centimeters. It could also have grown into nearby larger nerves or the skull.
SCC staging helps guide treatment decisions, with early stages often managed with surgical interventions and more advanced stages possibly requiring a combination of surgery, radiation and chemotherapy. The earlier the stage at detection, the better the prognosis generally is for the patient.
SCC treatment often depends on the stage of the cancer, its location, the patient’s overall health, and other individual factors. Effective treatment aims to eliminate the cancer, reduce the chance of recurrence, and preserve healthy skin tissue.
- Surgical Excision: This method is commonly used, especially for smaller tumors. The surgeon cuts out the cancerous tissue and a margin of healthy skin around it. The excised tissue is then examined under a microscope to ensure that all cancer cells have been removed.
- Mohs Surgery: Particularly useful for larger, recurrent, or hard-to-treat tumors, this procedure involves removing the skin growth layer by layer. Each layer is examined under a microscope until no abnormal cells remain, ensuring minimal removal of healthy tissue.
- Curettage and Electrodesiccation: After removing the surface of the skin cancer, the base of the tumor is scraped out with a curette. An electric needle is then used to cauterize the area, destroying the remaining cancer cells and minimizing bleeding.
- Radiation Therapy: High-powered energy beams, like X-rays, are used to kill cancer cells. It’s an option for those who can’t undergo surgery or for cancers that have a higher risk of recurrence.
- Superficial Radiotherapy (SRT): A low-energy radiotherapy that penetrates only a short distance below the skin surface. It effectively treats non-melanoma skin cancers, causing minimal damage to surrounding tissues.
- Cryosurgery: This technique uses extreme cold to freeze and destroy cancer cells. Liquid nitrogen is applied to the growth, causing it to freeze and slough off.
- Topical Medications: Certain creams, gels, or solutions can treat superficial SCC. These include 5-fluorouracil (5-FU) and imiquimod, which stimulate the immune system to destroy cancer cells.
- Photodynamic Therapy (PDT): A drug that makes cells more sensitive to light is applied, followed by shining a specific wavelength of light onto the area, which kills the cancer cells.
- Laser Therapy: Intense light is used to vaporize early-stage growths.
- Lymph Node Surgery: If SCC has spread to the lymph nodes, they may be surgically removed.
- Targeted Drug Therapy: Drugs like cetuximab block specific abnormalities in cancer cells, hampering their growth.
- Chemotherapy: Used for advanced SCC, especially if it has spread to other parts of the body. Drugs kill or slow the growth of cancer cells.
Treatment Side Effects
Like all medical treatments, SCC therapies can come with side effects. The nature and intensity of these side effects vary based on the treatment type and individual patient factors.
- Surgical Procedures: Common side effects include pain, swelling, scarring, and infection at the surgical site.
- Radiation and Superficial Radiotherapy: These might lead to fatigue, mild skin reactions, hair loss in the treated area and an increased risk of other cancers. SRT tends to have fewer deep tissue side effects due to its superficial nature.
- Cryosurgery: May cause pain, swelling, blistering, scarring and discoloration of the treated skin.
- Topical Medications: Redness, rash, itching, burning sensations, and changes in skin color can result from topical treatments.
- Photodynamic Therapy (PDT): The treated area can become red, swollen, and crusty. There’s also heightened sensitivity to light for a period.
- Chemotherapy: This systemic treatment can lead to fatigue, nausea, hair loss, increased infection vulnerability, and a higher likelihood of bruising or bleeding.
It’s essential for patients to discuss potential side effects with their medical team. Understanding the expected outcomes, side effects, and the recovery process can help patients make informed decisions and ensure they receive appropriate care following treatment.
SCC, though often successfully treated when detected early, can present significant complications if neglected. One major concern is its potential to invade deeper skin layers and underlying tissues, which can result in disfigurement, especially when located in prominent areas like the face.
Furthermore, while less common, there’s a risk of SCC metastasizing or spreading to other parts of the body, including vital organs and lymph nodes. This metastasis drastically complicates treatment approaches and can pose a severe threat to life. Additionally, even post-treatment, there’s always a risk of SCC recurring either in the initially affected area or elsewhere.
Preventing SCC revolves primarily around minimizing sun exposure and protecting the skin from harmful UV radiation. Adopting a habit of applying broad-spectrum sunscreen with an SPF of at least 30 is crucial, even on cloudy days or during winter months.
It’s advisable to wear protective clothing, including wide-brimmed hats, long-sleeved shirts and sunglasses when outdoors. Seeking shade during peak sun hours, usually between 10 a.m. and 4 p.m., can also minimize exposure to UV radiation. Avoiding tanning beds and sun lamps, which emit UV rays, further reduces this risk.
Beyond UV protection, it’s essential to monitor the skin for any changes. Regular self-examinations and annual dermatological checkups can aid in early detection, ensuring that any suspicious lesions or growths are addressed promptly. Maintaining a strong awareness of one’s skin and the dangers of prolonged UV exposure is paramount in effectively preventing SCC and ensuring skin health.
The prognosis for SCC is generally favorable when detected and treated early. Most localized cases of SCC, when treated promptly, result in full recovery. The five-year survival rate for localized SCC is above 90%. However, the prognosis can become more complex if the carcinoma has penetrated deeper layers of the skin, affected a significant area, or has features suggesting a high risk of recurrence.
The most concerning scenario is when SCC metastasis or spreads to lymph nodes or other parts of the body; this significantly lowers the survival rate. Factors that can influence the prognosis include the tumor’s size, depth and location, as well as the patient’s overall health. In essence, early detection and intervention are key to a favorable SCC prognosis
SCC Treatment at Sheba Medical Center
In conclusion, SCC is a manageable condition with a high treatment success rate when detected and treated early. Prevention through protective measures against UV radiation and regular skin examinations play a pivotal role in reducing the risk of developing SCC.
If treatment is needed, there is a range of options catering to different stages and severities of the condition. For those seeking world-class care, Sheba Medical Center, the largest medical center in the Middle East and one of the top ranked hospitals in the world, stands out as a premier SCC treatment center. Renowned for its cutting-edge technology and experts, Sheba attracts patients from around the world, offering personalized care to ensure the best possible outcomes.
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