Loading icon
Press enter or spacebar to select a desired language.
Health Information Center

Skin Cancer—Overview

  • Laurie LaRusso, MS, ELS
Publication Type:


Skin Cancer—Overview

(Basal Cell Carcinoma; Squamous Cell Carcinoma)


Skin cancer is the growth of abnormal skin cells. These cancer cells grow out of control and damage nearby healthy tissue. Some types of skin cancer can also spread to other parts of the body. There are different types of skin cancer—the three most common kinds are:

Most skin cancers can be cured when found early. Certain skin cancers can be fatal if found in late stages.


Nucleus factsheet imagehttp://services.epnet.com/getimage.aspx?imageiid=73637363si55551326.jpgsi55551326.jpgNULLjpgsi55551326.jpgNULL\\hgfiler01a\intellect\images\si55551326.jpgNULL8NULL2008-11-072313907363_21337Copyright © Nucleus Medical Media, Inc.


Cancer happens when cells in the body divide without control or order. Over time, the cells can form into a growth or tumor. The growths invade and take over nearby tissue. The reason why this happens is not known. Genetics and the environment (sun) can play a role.

UV radiation damages the DNA of skin cells. Both the sun and tanning beds make these UV rays. The damage may build up over a lifetime. It can also happen after a brief intense exposures, like sunburns.

Risk Factors

While skin cancer can develop in anyone, it is more likely to develop in people with:

  • Fair skin that freckles easily
  • Red or blonde hair
  • Blue or green eyes
  • Light natural skin color

Other things that may raise the risk of skin cancer are:

  • A past skin cancer
  • Family history of skin cancer
  • Excessive sun exposure without protective clothing or sunscreen
  • Regular use of tanning beds
  • Skin damage from burns or infections
  • Exposure to arsenic or industrial coal tar
  • Radiation therapy
  • Light treatments for psoriasis, especially psoralen ultraviolet A (PUVA)
  • A weak immune system from illness, medicine, or an organ transplant
  • Certain genetic diseases, such as basal cell nevus syndrome or xeroderma pigmentosum


The first symptoms of skin cancers are a change in the skin. One type of change is actinic keratosis. It is considered a precancerous change. This scaly, crusty change to skin can develop into skin cancer if left untreated.

Skin changes caused by cancer depend on the type of skin cancer. For example:

Basal cell carcinoma may appear as a:

  • Slowly expanding, painless growth
  • Bleeding scab or sore that heals and recurs
  • Flat, firm, pale area
  • Small, raised, pink, red, or pearly area that may bleed easily
  • Large oozing, crusted area

Squamous cell carcinoma may appear as a:

  • Growing lump with rough, scaly, or crusted surfaces
  • Slow-growing flat, reddish patch in the skin
  • Recurrent, nonhealing ulceration or bleeding

Skin cancers can happen anywhere, but are more common on places exposed to the sun. Finding skin cancer early offers the best chance for a cure. Steps to find a skin cancer are:

  • Telling the doctor about any skin changes or symptoms when they appear
  • Regular skin checks by a doctor—for those with lighter skin
  • Doing regular skin screenings at home as instructed by the doctor


The doctor will ask about symptoms and past health. A physical exam will be done. If the doctor suspects cancer, a biopsy will be done. A sample of the skin will be taken and tested for the cancer cells.

The nearby lymph nodes (glands) may be checked if the growth is large. Cancer in the lymph nodes means the cancer may have spread. More tests will be needed if cancer is found in the lymph nodes.

Tests are used to assess the stage of cancer. Skin cancer may be stage 0 to 4. Stage 0 and 1 cancers only affect the local area. Stage 4 cancer has spread to other areas of the body. Staging will help to guide treatment.


Treatment will depend on the type of cancer, the size of the growth, and the person's health. Options may include:


To help reduce the risk of skin cancer:

  • Avoid spending too much time in the sun.
  • Avoid the sun during peak sunlight hours.
  • Protect your skin from the sun with clothing. Wear a shirt, sunglasses, and a hat with a broad brim.
  • Use broad-spectrum (UVA and UVB) sunscreen on skin that will be exposed to the sun. Use sun protection factor (SPF) of 30 or more.
  • Use a protective lip balm.
  • Wear sunglasses with 99% or 100% UV absorption.
  • Do not use sun lamps or tanning booths.

If you see any changes in your skin contact your doctor for a skin exam.





  • Basal and squamous cell skin cancer. American Cancer Society website. Available at: https://www.cancer.org/cancer/basal-and-squamous-cell-skin-cancer.html.
  • Basal cell carcinoma of the skin. EBSCO DynaMed website. Available at: https://www.dynamed.com/condition/basal-cell-carcinoma-of-the-skin.
  • Cutaneous squamous cell carcinoma (SCC). EBSCO DynaMed website. Available at: https://www.dynamed.com/condition/cutaneous-squamous-cell-carcinoma.
  • Firnhaber JM. Basal cell and cutaneous squamous cell carcinomas: Diagnosis and Treatment. Am Fam Physician. 2020;102(6):339-346.
  • Skin cancer treatment (PDQ)—patient version. National Cancer Institute website. Available at: https://www.cancer.gov/types/skin/patient/skin-treatment-pdq.
  • Sunscreen FAQs. American Academy of Dermatology website. Available at: https://www.aad.org/public/everyday-care/sun-protection/shade-clothing-sunscreen/sunscreen-faqs. A


  • Mark Arredondo, MD
Last Updated:

This content is reviewed regularly and is updated when new and relevant evidence is made available. This information is neither intended nor implied to be a substitute for professional medical advice. Always seek the advice of your physician or other qualified health provider prior to starting any new treatment or with questions regarding a medical condition.