Skin cancers are the most common type of cancer seen in white races. Gross differences are noted in the percentage of skin cancer in the Asians (2–4%) and Blacks (1-2%) as compared to the Caucasians (35–40%). Although the incidence of skin cancers in India is lower as compared to the Western world, an absolute number of cases may be significant due to a large population. Men are more frequently affected than women.
There are several types of skin cancer. The main types of skin cancer are squamous cell carcinoma (SCC), basal cell carcinoma (BCC), and melanoma. Melanoma is a rarely found skin cancer but much more likely to invade nearby tissue and spread to other parts of the body. In fact, most deaths occurred from skin cancer are caused by melanoma. SCC has been reported to be the most prevalent skin cancer in India.
Causes of Skin Cancer:
a) Unprotected exposure to excessive ultraviolet radiation, primarily from the Sun.
b) Fair skin colour, and family history of skin cancer.
c) Exposure to causative agents like arsenic, coal tar and various hydrocarbons and history of radiation exposure.
d) Human papillomavirus (HPV) may play a role in immunosuppressed patients, particularly organ transplant recipients (18 times higher risk in kidney transplant patients than that in the general population).
e) Kangri cancer typically occurs following the use or exposure of kangri (a firepot tucked in between the thighs), is seen exclusively among the people of the Kashmir valley.
f) They can arise from burns scars (also called Marjolin’s ulcer)” or in sites of chronic injury or irritation such as scars, ulcers and sinuses or certain skin conditions like Lupus etc.
Any changes in the previous skin conditions such as a) Pain, b) increased redness, c) sores or bleeding, d) hardening or thickening, and e) increased size – may be a warning sign that it is developing into a squamous cell carcinoma.
Skin biopsy is necessary to confirm the clinical suspicion of skin cancer.
Treatments for skin cancer are more effective and less disfiguring when it is found early.
The surgical resection requires complete excision of the tumour with clear margins (2-4mm) in all directions (surrounding as well as deep). More margins are required for bigger tumours, tumours in high-risk areas, or recurrent tumours. Mohs surgery has the greatest success rate (95%) and should ordinarily be considered the preferred treatment.
- Curettage of the tumour with electrodesiccation.
- Cryosurgery using liquid nitrogen
- Laser surgery: uses a laser beam (a narrow beam of intense light) to remove a tumour.
- Dermabrasion: The Removal of top layer of skin using a rotating wheel or small particles to rub away skin cells.
Photodynamic therapy (PDT)
- Radiotherapy: If surgery is not feasible or it resulting in unacceptable cosmetic results/disfigurement then radiotherapy alone is used. It is also used in the patient who is medically unsuitable for surgery or who declines, surgery. Radiotherapy is also used in post-operative settings for large tumours, no clear margins after surgery, unusually aggressive cancers and in cases where regional lymph nodes are involved. Radiotherapy is also used role in distant metastatic sites like bone, brains etc. which is more commonly seen with melanomas. In these situations, SRS/SBRT/Cyberknife can also be offered.
- Chemotherapy: Chemotherapy has no role in skin cancers. It is used in cases there is a distant spread of cancer especially melanomas.
This article is contributed by Dr Manoj Tayal, Associate Director, Medanta Cancer Institute. The cancer institute is part of Medanta Hospital located in Gurugram. This article has been published for basic public awareness purpose only and should not be taken as guidelines for patients.