Skin cancer involves the uncontrolled division of skin cells. Due to uncontrolled division, the cells accumulate and form a tumor. The tumor may be benign or malignant. The most common skin cancers are squamous cell carcinoma and basal cell carcinoma. Skin cancer in India has a share of less than 1% of all cancer diagnoses.
Types of Skin Cancer
There are the following types of skin cancer:
- Basal cell carcinoma: It develops in those areas of the body exposed to the sun.
- Squamous cell carcinoma: This cancer occurs in the squamous cells of the epidermis.
- Melanoma: Melanocytes are cells in the skin responsible for secreting melanin. Skin cancer formed in the melanocytes is called melanoma.
- Other types: The other types of skin cancer include Merkel cell carcinoma, Kaposi sarcoma, and sebaceous gland carcinoma.
Symptoms of Skin Cancer
Symptoms depend upon the type of skin cancer.
- Basal cell carcinoma: Symptoms include waxy or pearly bumps, flat and flesh-colored growth, and pinkish skin patches.
- Squamous cell carcinoma: Symptoms include a scaly patch, a red-colored bump, and a flat lesion.
- Melanoma: Symptoms include large brown colored spots, a mole that changes in size and color, and a painful lesion with itching and burning sensation.
Causes of Skin Cancer
A common cause of skin cancer is exposure to sunlight. However, skin cancer also occurs in areas of the body not exposed to sunlight. It indicates that other factors contribute to the development of skin cancer. These factors include:
Family and personal history of skin cancer
Presence of precancerous lesions or moles
Compromised immune system
Exposure to toxic substances, such as arsenic
Radiation treatment for acne and eczema
Diagnosis of Skin Cancer
Skin cancer can be diagnosed through the following techniques:
- Physical examination: The doctor may perform a physical examination if cancer is the cause of alteration in the skin characteristics.
- Skin biopsy: If the doctor suspects cancer, the patient may undergo a biopsy. A small sample of skin tissue is obtained and evaluated under the microscope.
- Imaging tests: Imaging tests may also be performed to evaluate if cancer spreads to nearby lymph nodes.
Treatment for Skin Cancer
Treatment options for skin cancer are:
Removing small skin cancers: In this procedure, the surgeon removes the entire growth of the cancerous tissue through biopsy. This technique is effective in cases where the skin cancer is localized and confined to a smaller area.
Excisional surgery: This method is used in all types of skin cancer. In this method, the surgeon removes the cancerous tissues and the margins of healthy tissues. Sometimes, removing the extra normal skin is recommended by making a wider excision.
Freezing: This method is also known as cryosurgery. In this procedure, the doctor destroys early skin cancer with the help of liquid nitrogen. Liquid nitrogen freezes the cancerous tissues, and the dead tissue is removed when it thaws.
Cryotherapy: This procedure is also known as curettage and electrodesiccation. The technique is used after most of the cancerous growth is removed by other methods. The doctor uses the circular blade, known as a curet, to remove the layer of cancer cells. Then, the electric needle destroys the remaining cancer cells. To freeze the margins and base of the treated area, the doctor may also use liquid nitrogen.
Mohs surgery: This surgery removes the cancerous tissue without affecting the surrounding healthy cells. A layer of skin is removed and is immediately analyzed under the microscope. Removal of the layer continues until no cancerous cells are visible under the microscope.
Chemotherapy: It involves the use of drugs that interfere with the vital processes of the cancerous cells and either destroys them or slows their growth. Anti-cancer drugs in the form of ointments, gels, and lotions are effective in the case of localized skin cancer. In case cancer spreads to other organs, systemic chemotherapy is used.
Radiation therapy: Radiation therapy involves a controlled dose of radiation to kill cancerous cells. Squamous cell carcinoma and basal cell carcinoma are treated with external beam radiations. Radiation therapy effectively treats various skin cancers, and skin function and cosmetic appearance are better preserved with this therapy.
Biological therapy: Biological therapy is also used to treat skin cancer. The doctor, through biological therapy, administers drugs that either boost the immune system or interfere with the process of cancerous cells that assists them in hiding from the immune system.
Photodynamic therapy: Photodynamic therapy also helps in managing skin cancer. The doctor uses a combination of very bright light and light-sensitizing drugs to kill the cancerous tissues. Light sensitizing cream is rubbed on the cancerous skin and the surrounding area. When the light falls on the drug, it creates a type of oxygen that kills the cells.
Frequently Asked Questions
How should I prevent skin cancer?
Although there is no confirmed method to prevent skin cancer, the risk can be reduced through the following measures:
- Avoid prolonged sunlight exposure
- Apply a broad-spectrum sunscreen with optimum SPF
- Wear a hat and full sleeve shirt before going in the sunlight
- Consult with the doctor if you have any symptoms of precancerous skin lesion
What are the side effects of skin cancer treatment?
The side effects depend upon the therapy used for treating skin cancer. Side effects include nausea, vomiting, oral sores, rashes (with chemotherapy), pain and swelling (with surgery), and skin irritation (with radiation therapy).
How do UV rays cause skin cancer?
The ultraviolet rays reach deep into the skin cells and alter the information present in the genetic material. It results in uncontrolled cell division.
What is the prognosis of skin cancer?
The 5-year survival rate in case of localized melanoma is 99%, while regional melanoma is 68%. Patients with melanoma that spreads to distant lymph nodes and other body organs have a 5-year survival rate of 30%.