Cancer of the skin occurs when skin cells proliferate and replicate uncontrollably and disorderly. Typically, new skin cells arise when old or damaged cells die or become obsolete. When this process does not function properly, rapid cell development (some of which may be abnormal) occurs. This clump of cells may be noncancerous (benign), which does not spread and does not cause harm, or cancerous, which may spread to neighboring tissue or other sections of your body if not detected and treated promptly.

Ultraviolet (UV) rays from the sun are frequently the cause of skin cancer. The UV radiation emitted by indoor tanning beds is a Category 1 carcinogen, along with tobacco and asbestos. The prevention of carcinogenic exposures can result in cancer prevention. It is believed that indoor tanning causes about 450,000 new cases of skin cancer each year, including over 10000 melanomas. Despite significant investment in preventative initiatives, including several well-designed campaigns by the Centers for Disease Control and Prevention and organizations focusing on skin cancer prevention, efforts to influence the incidence of skin cancer have encountered a brick wall. One in five teens and more than 40% of college students continue to use tanning beds.

Skin cancer is the most often diagnosed malignancy in the United States. Around 20% of Americans will develop skin cancer in their lifetime. Every day, over 9,500 Americans are diagnosed with skin cancer. Five or more sunburns increase the risk of developing melanoma by double. If diagnosed and treated early, the five-year survival rate is 99%.

Around 30% more non-Hispanic whites are diagnosed with skin cancer than non-Hispanic blacks or Asian/Pacific Islanders. Those with darker skin are frequently detected with skin cancer at later stages when it is more difficult to treat. 25% of African Americans with melanoma are diagnosed after cancer has spread to adjacent lymph nodes.

Overexposure to sunlight is the leading cause of skin cancer, especially when it results in sunburn and blistering. The sun's ultraviolet (UV) rays destroy the skin's DNA, causing abnormal cells to develop. These aberrant cells divide fast and disorderly to build a mass of cancer cells. Additionally, frequent skin contact with certain substances, such as coal and tar, is another cause of skin cancer.

Where does skin cancer develop?

Sun-exposed areas of your skin are most susceptible to developing skin cancer, including your face (including your lips), ears, neck, arms, chest, upper back, hands, and legs. But it can also form in less sun-exposed and more concealed regions, including between your toes, under your fingernails, on your palms, soles, and genital area.

The types and names of skin cancers are correlated with the location of skin cancer development, i.e., which skin cells.

Most skin malignancies begin in the epidermis, the outermost layer of skin. The epidermis is composed of three primary cell types:

- Squamous cells: They are flat cells in the epidermis' outermost layer. They continually shed cells as new ones form. Cancer that can develop in these cells is known as squamous cell carcinoma.

- Basal cells: These cells are positioned underneath the squamous cells. They proliferate, replicate, and eventually grow flatter and migrate upward in the epidermis to create new squamous cells, which replace the sloughed-off dead squamous cells. Cancer that originates in the basal cells of the skin is known as basal cell carcinoma.

- Melanocytes: These cells produce melanin, the brown pigment that gives skin its color and defends against some UV radiation from the sun. Melanoma is the name of a form of skin cancer that develops in melanocytes.

Most at Risk for Skin Cancer

Although anyone can acquire skin cancer, you’re at elevated risk if you:

· Spend a large amount of time working or playing in the sun.

· Get easily burnt; have a history of sunburns.

· Reside in a sunny, high-altitude environment.

· Tan or use tanning beds.

· Has numerous or irregularly-shaped moles.

· Suffer from actinic keratosis.

· Have a family history of skin cancer.

· Have undergone an organ transplant.

· Consume drugs that inhibit or impair the immune system.

· Have received UV light therapy for the treatment

of skin disorders including eczema or psoriasis.

Skin Cancer Diagnosis

First, your dermatologist may ask if you have observed any changes in existing moles, freckles, or other skin spots, or if you have observed any new skin growths. Your dermatologist will then inspect your entire skin, including your scalp, ears, palms of your hands, soles of your feet, between your toes, genital area, and buttocks.

If a worrisome skin lesion exists, a biopsy may be conducted. During a biopsy, a tissue sample is extracted and transported to a laboratory for microscopic examination by a pathologist. If your skin lesion is skin cancer, your dermatologist will identify the type and explain treatment options.

How is skin cancer treated?

Cancer treatment depends on its stage. Skin cancer stages range from stage 0 to stage IV. The greater the number, the further the spread of cancer.

If the cancer is tiny and confined to the skin's surface, a biopsy may be sufficient to remove all the cancerous tissue. Some popular therapies for skin cancer, alone or in combination, include:

1. Cryotherapy

Liquid nitrogen is used in cryotherapy to freeze skin cancer. Following treatment, the dead cells shed. This approach can be used to treat precancerous skin lesions known as actinic keratosis and other tiny, early malignancies confined to the top layer of skin.

2. Excisional surgery

This procedure involves removing the tumor and some healthy tissue surrounding it to ensure that all cancer has been eradicated.

3. Mohs surgery

Mohs surgery preserves normal tissue. Typically, it is used to treat basal cell and squamous cell malignancies near sensitive or cosmetically significant areas, such as the eyelids, ears, lips, forehead, scalp, fingers, and genital region.

4. Curettage and electrodesiccation

The method uses a device with a sharp looping edge to scrape across the tumor and eliminate cancer cells. Following this, the region is treated with an electric needle to eliminate any leftover cancer cells. This method is frequently used to treat basal cell, squamous cell, and precancerous skin lesions.

5. Chemotherapy and immunotherapy

Chemotherapy uses drugs to eliminate cancer cells. Anticancer drugs can be applied directly to the skin (topical chemotherapy) if the cancer is confined to the outermost layer of the skin, or given orally or intravenously (IV) if cancer has spread to other regions of the body. Immunotherapy employs the immune system to eliminate cancer cells.

6. Radiation therapy

Radiation therapy is a method of cancer treatment that employs radiation (intense beams of energy) to destroy cancer cells or prevent their growth and division.

7. Photodynamic therapy

In this therapy, your skin is covered with medicine, which is subsequently activated by a blue or red fluorescent light. Photodynamic therapy eliminates precancerous cells without harming healthy cells.

Almost one in five individuals will acquire skin cancer at some point in their lives. Almost of skin cancers are curable if detected and treated early. Including the seven types of treatments listed above. Look for changes in the size, shape, and color of skin growth. See your dermatologist annually for a professional skin examination.

REFERENCES:

www.ncbi.nlm.nih.gov/pmc/articles/PMC5489348/

https://my.clevelandclinic.org/health/diseases/15818-skin-cancer#symptoms-and-causes