Squamous cell cancer (SCC), also known as squamous cell carcinoma, is a type of cancer. It develops in squamous cells, which are the thin, flat cells that make up the outermost layer of your skin. Squamous cells are also found in other parts of your body such as your lungs, mucous membranes, digestive tract, and urinary tract.
SCC that forms in your skin is known as cutaneous SCC (cSCC). cSCC develops due to changes in the DNA of squamous cells, which causes them to multiply uncontrollably. It often forms on parts of your skin frequently exposed to sunlight like your face, neck, or arms.
Keep reading to learn more about this type of skin cancer, what it looks like, what causes it, and how it’s diagnosed and treated.
Cutaneous SCC (cSCC) is a cancer that develops in the squamous cells of your skin. According to the Skin Cancer Foundation, about
Although cSCC isn’t life threatening, it can become dangerous if it goes untreated. When treatment isn’t received quickly, the growths can increase in size and spread to other parts of your body, causing serious complications.
People with cSCC often develop scaly, red patches, open sores, or warty growths on their skin. These abnormal growths can develop anywhere, but they’re most often found in areas that receive the most exposure toultraviolet (UV) radiation, either from sunlight or from tanning beds or lamps.
Oral SCC also makes up more than90 percentof mouth cancers. Lung SCC makes up about
Your skin has multiple layers. The outer, protective layer of the skin is known as theepidermis。表皮有三种主要细胞类型：
- keratinocytes (skin cells, also called squamous cells)
- melanocytes (pigment-producing cells)
- Langerhans cells (immune cells)
The cells of the epidermis are constantly shedding to make way for fresh, new skin cells.
However, when certain genetic changes occur in the DNA of any of these cells, skin cancer can occur. The main types of skin cancer are:
- 鳞状细胞癌
- basal cell carcinoma
- 恶性黑色素瘤
Squamous cell cancer
Squamous cells are the cells closest to your skin’s surface, and their purpose is to line your skin. cSCC often develops in areas of the body that are frequently exposed to UV radiation, such as your face, hands, and ears.
基础细胞癌
Basal cells sit below the squamous cells, and they’re constantly dividing to form new cells. According to the American Cancer Society, basal cell carcinoma makes up about
Like cSCC, basal cell cancer typically develops in areas exposed to UV rays, particularly your face and neck. This type of cancer tends to grow slowly, and it rarely spreads to other parts of your body.
但是，如果基础细胞癌未经治疗，它最终会扩散到您的骨骼和其他组织。
Melanoma
Along with basal cells, melanocytes are located in the deepest section of your epidermis. These cells are responsible for producing melanin, the pigment that gives skin its color. When cancer develops in melanocytes, the condition is known as恶性黑色素瘤。
恶性黑色素瘤不如鳞状细胞和基础癌症普遍，但是当不治疗时，它更有可能生长和扩散。
cSCC地区经常发生exposed to UV radiation, such as your face, ears, and hands. However, it can also appear in your mouth, around your anus, and on your genitals.
Symptoms of cSCC can include:
- an open sore that can have raised borders
- a scaly, reddish patch of skin
- a brown spot resembling an age spot
- a wart-like growth
- 旧的疤痕，胎记或痣的新增长
- a horn-shaped growth
- a firm and dome-shaped growth
According to theAmerican Academy of Dermatology，CSCC最常见的是红色或粉红色。也可能是：
- brown
- black
- yellowish
- white
In your mouth, this cancer can cause:
- lip or mouth sores that don’t heal
- sore or rough patches in your mouth
- aloose tooth
- white or reddish patches
- painful swallowing
- a growth inside your mouth
如果您发现CSCC的任何症状或经历酸痛或不愈合的酸痛或成长，请立即与您的医生或皮肤科医生预约。早期诊断和治疗对于预防并发症至关重要。
cSCC is caused by mutations that occur in squamous cell DNA. These changes cause abnormal cells to multiply out of control.
UV radiation is the most common cause of the DNA mutations that lead to cSCC and other skin cancers.
原因of squamous cell cancer
Most cases of cSCC are attributed to exposure to UV radiation from sunlight or indoor tanning equipment like tanning lamps and beds. Other potential causes include:
- Genetics.Genetic factorsseem to play a role in the development of cSCC. A 2015 study found that people with a family history of cSCC are about
four times more likely to develop it. - Smoking.People who smoke are
more likely to develop cSCC, especially on their lips. Smoking is the primary risk factor for developing lung cSCC and other non-small cell lung cancers. - Chemical exposure.接触某些化学物质如煤焦油、paraffin, some petroleum products, and arsenic may contribute to cSCC development.
- Radiation exposure.Undergoingradiation therapyslightly increases your risk of developing skin cancer in the part of your body that received treatment.
- Immunosuppression.Immunosuppression contributes to the development of cSCC. For example, organ transplant recipients have a
65至250次 higher risk of developing cSCC than people in the general population. - Severe burn scars and sores.cSCC can develop in severe burn scars, sores, or ulcers that have been on your body for many years.
Risk factors for squamous cell cancer
Risk factors for cSCC include:
- 皮肤白皙
- having light-colored hair and blue, green, or gray eyes
- 长期暴露于紫外线辐射
- living in sunny regions or at a high altitude
- having a history of multiple severe sunburns, especially if they occurred early in life
- having a history of being exposed to chemicals, such as arsenic
- having a history of immunosuppression
- history of
severe burn scars , ulcers, or sores
治疗for cSCC varies. Treatment is based on:
- 癌症的程度和严重程度
- your age
- 您的整体健康
- the location of the cancer
If cSCC is caught early, the condition can usually be successfully treated. It becomes harder to cure once it has spread. Many treatments can be performed as in-office procedures. Treatments may include:
- Mohs micrographic surgery.InMohs surgery，您的医生使用手术刀去除皮肤异常和一些周围的组织。立即在显微镜下检查样品。如果样品中有任何癌细胞，则重复该过程，直到找不到癌细胞。
- Excisional surgery.During excisional surgery, your doctor removes the cancer cells as well as a thin layer of healthy skin in the surrounding area. Stitches are used to close the wound. The sample is then sent to a laboratory to ensure the entire cancerous area has been removed.
- Electrosurgery.Also called electrodesiccation and curettage,electrosurgeryinvolves scraping off the cancer and burning the skin to kill cancer cells. This process is typically done more than once to ensure thorough treatment and complete removal of the cancer.
- Cryosurgery.Duringcryosurgery, your doctor uses liquid nitrogen to freeze and destroy the cancerous tissue. Like electrosurgery, this treatment is repeated multiple times to make sure all cancerous tissue has been eliminated.
- Radiation.With radiation, high energy X-rays kill cancer cells. This treatment is administered externally by a machine, which aims the rays at the affected area. Radiation is often performed multiple times a week for several weeks.
- 光动力治疗。Also known as PDT,photodynamic therapyinvolves the application of a photosensitizing substance to the cancerous areas. After 1 to 3 hours or longer, the areas that were medicated are exposed to strong light for several minutes. This activates the medication that was applied and kills abnormal cells.
- Systemic drugs.Several types of systemic drugs are
FDA批准 to treat cSCC, including cemiplimab-rwlc (Libtayo) and pembrolizumab (Keytruda). Systemic drugs act on your whole body and are often used for aggressive cSCC.
Non-FDA-approved methods for treating squamous cell carcinoma
Some doctors may also use laser surgery and topical medications to treat cSCC. However, the Food and Drug Administration has not approved these methods for treating cSCC:
- Laser surgery.During laser surgery, your doctor uses a concentrated beam of light to remove areas of skin that are abnormal.
- Topical medications.Medications, such as 5-fluorouracil and imiquimod, that are applied on the skin to treat other skin cancers may also help treat cSCC.
Once cSCC has been treated, it’s critical to attend all follow-up visits with your doctor. cSCC can return, and it’s important to monitor your skin for any precancerous or cancerous areas at least once per month.
Your doctor will first perform a physical exam and inspect any abnormal areas for signs of cSCC. They’ll also ask you about your medical history. If cSCC is suspected, your doctor may decide to take a活检to confirm the diagnosis.
A biopsy usually involves removing a very small portion of the affected skin. The skin sample is then sent to a laboratory for testing.
In some cases, your doctor may need to remove a larger part or all of the abnormal growth for testing. Talk with your doctor about any potential scarring or biopsy concerns.
After receiving treatment for cSCC, be sure to attend all follow-up visits with your doctor. It’s possible for the cancer to return, so it’s critical to check your skin for any signs of cancer or precancer at least once per month.
To help reduce your risk of cSCC, follow these tips when possible:
- Limit your sun exposure.
- Avoid the sun during the hottest part of the day, which is between 10 a.m. and 4 p.m.
- Wear sunscreen that has an SPF of at least 30 whenever you go out in the sun.
- Wear sunglasses with UV ray protection.
- 戴帽子并在外面工作时遮住皮肤。
- Avoid using tanning beds and lamps.
- Protect your skin during winter as well because winter UV rays can be especially dangerous.
- Check your skin each month for any new or abnormal growths.
- See a dermatologist once per year for a full-body skin check.
Early detection of cSCC is key to successful treatment. If cSCC isn’t treated in its early stages, the cancer may spread to other areas of the body, including the lymph nodes and organs. Once this occurs, the condition can be life threatening.
People with weakened immune systems due to certain medical conditions, such asHIV, AIDS, orleukemia, have a greater risk of developing more serious forms of cSCC.
It’s a good idea to see a doctor right away if you suspect you have any type of skin cancer.