Medical Centric

SKIN CANCER

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SKIN CANCER

Skin cancer is a type of cancer arising from the skin.

  • It mostly develops in the area of the skin that is exposed to the sun, but it can also form on areas of skin not ordinarily exposed to sunlight.
  • There are three major types of skin cancer: basal-cell skin cancer (BCC), squamous-cell skin cancer (SCC) and melanoma.
  • The first two along with some other less common skin cancers are known as nonmelanoma skin cancer (NMSC).
  • Basal-cell skin cancer usually develops in the sun-exposed area of the body, such as the neck and face. This type grows slowly and can damage the tissue around it but it is unlikely to spread to distant areas or become life-threatening. It is the most common resulting in about 80% of nonmelanoma skin cancer.
  • Squamous-cell cancer also usually occurs in sun-exposed areas of the body, such as the face, hands, and ears. This type is more likely to spread. People having dark skin shade are more likely to develop this type in areas that aren’t often exposed to the sun. It is the second most common resulting in about 20% of all nonmelanoma skin cancer.
  • Basal and squamous cancer rarely result in death.
  • Melanomas are the most aggressive. This type can develop anywhere on the body and develops from melanocytes- the cells that give skin the normal color, they can also develop in existing benign moles that become cancerous. In men, they are likely to develop on the face, chest, and back. In women, they are likely to develop on the lower legs. Melanomas can be cured if detected and treated early and can spread to other parts of the body if left untreated. Melanomas may eventually lead to death. Melanomas are the least frequent of the 3 common skin cancers.
  • In 2012, melanoma occurred in 232,000 people and resulted in 55,000 deaths worldwide.
  • White people in South Africa, New Zealand and Australia have the highest rates of melanoma in the world.

CAUSES

The primary environmental cause of skin cancer is ultraviolet radiation from sun exposure.  Sun exposure doesn’t really explain skin cancers that develop on skin not exposed to sunlight. This suggests that there are other factors that may contribute to the development of skin cancer, such as:

  • Smoking tobacco
  • HPV infections. This increases the risk of squamous-cell skin cancer.
  • Ionizing radiation such as x-rays, artificial UV found in tanning beds. The World Health Organization now places people who use artificial tanning beds in its highest risk category for skin cancer.
  • Use of any immunosuppressive medications such as cyclosporine A, calcineurin inhibitor, and azathioprine increase the risk.
  • Some genetics syndromes including congenital melanocytic nevi syndrome.

Other factors that may increase the risk of developing skin cancer:

  • Fair skin
  • A history of sunburns
  • Excessive exposure to the sun
  • Moles
  • Sunny or high-altitude climates
  • A family history of skin cancer
  • A weakened immune system
  • Exposure to radiation and other substance such as arsenic.

SYMPTOMS

  • Painless raised area of skin that may appear shiny with blood vessel running over it
  • Hard lump with a scaly top
  • A mole that has changed in size, color, has irregular edges, has more than one color, itches or bleeds.
  • Dark lesions on the palms, soles, fingertips or toes
  • A flat, flesh-colored or brown scar-like lesion

DIAGNOSIS AND TREATMENT

During diagnosis, the doctor will:

  • Examine your skin to determine whether changes on your skin are likely to be skin cancer.
  • Skin biopsy, where suspicions-looking skin are removed to be tested in the lab. This can determine if you have skin cancer and also the type of skin cancer that you have.

The stages of the cancer are determined based on how far cancer has spread. This will help the doctor to determine the best treatment option. Tests such as imaging tests may be used.

Nonmelanoma skin cancer stages range from stage 0 where the cancer is still confined to the epidermis to stage IV, where cancer has spread beyond the primary tumor site to the lymph nodes and bone or tissue, and the cancer is larger than 3 cm

Melanoma stages range from stage 0 where the cancer is confined to the epidermis to stage IV, where cancer has metastasized from the original site to the lymph nodes, organs and other tissues in the body.

TREATMENT

Treatment options depend on the size, type, depth and location of the lesions.

If the cancer is small and limited to the surface of the skin, removing the cancerous growth through skin biopsy may be the only treatment required.

If additional treatment is needed, options are:

  • Freezing with liquid nitrogen (cryosurgery)
  • Excisional surgery
  • Mohs surgery for larger, recurring or hard to treat skin cancer
  • Chemotherapy
  • Radiation therapy
  • Photodynamic therapy that uses laser lights and drugs to destroy cancerous cells.
  • Curettage and electrodesiccation
  • Biologic immunotherapy for melanomas. Biologic immunotherapy agents such as ipilimumab, pembrolizumab, and nivolumab