Nonmelanoma Skin Cancer


Nonmelanoma skin cancer encompasses all skin cancer types except melanoma. The most common types within this broader category are basal cell carcinoma and squamous cell carcinoma.

Treatment approaches for nonmelanoma skin cancer vary depending on the specific subtype, often involving surgical removal of the affected cells.

Types of nonmelanoma skin cancer

Basal cell carcinoma

Basal cell carcinoma (basal cell cancer) is the most common form of skin cancer, constituting approximately 80% of nonmelanoma skin cancers. It originates from keratinocytes, cells located in the skin’s outermost layer.

Typically, basal cell carcinoma tumors manifest as small, raised, shiny, or pearly bumps, though their appearance can vary. Commonly emerging in sun-exposed areas like the face, head, neck, arms, and hands, these tumors generally progress slowly and seldom metastasize to other body parts. While nearly all cases of basal cell carcinoma are treatable, recurrence post-treatment is possible in some instances.

While basal cell carcinoma seldom metastasizes to distant areas, untreated cases may extend below the skin, potentially reaching the bone and causing damage or disfigurement. Moreover, it heightens the risk of developing additional basal cell carcinomas or other skin cancer types elsewhere on the body.
Typically characterized by slow growth, basal cell carcinomas can often be effectively treated through lesion removal. The five-year survival rate for patients with basal cell carcinoma is estimated to be nearly 100% due to its rare metastasis. Given the potential for recurrence, regular follow-up appointments with a healthcare provider are recommended.

Squamous cell carcinoma

Squamous cell carcinoma commonly originates in sun-exposed areas of the skin such as the face, head, neck, arms, and hands. However, it can also develop in other regions of the body, including the genital area.

As the second most prevalent type of skin cancer, squamous cell carcinoma arises from keratinocytes in the epidermis. In cases where it develops on the genitals, it’s frequently associated with Human Papillomavirus (HPV) infection.

Tumors of squamous cell carcinoma often manifest as rough or scaly patches in shades of red to pink on the skin. They may also resemble crusted or open sores that resist healing or thickened, wart-like areas.

While squamous cell carcinoma has a greater tendency to grow and metastasize compared to basal cell cancer, this occurrence remains relatively rare. Most cases of squamous cell carcinoma are diagnosed early enough for successful treatment, but staging may be necessary for patients with risk factors such as a compromised immune system, which heightens the likelihood of spread.

When detected early, squamous cell carcinoma boasts a five-year survival rate of 99%. However, this rate may vary among patients diagnosed with advanced-stage cancer. It’s important to note that precise figures for survival rates are not available as cancer registries typically do not document survival rates for basal cell carcinoma and squamous cell carcinoma.

Merkel cell carcinoma

Merkel cell cancer is an uncommon form of skin cancer that can develop anywhere on the body, although it typically emerges on sun-exposed regions like the face, neck, and arms. Typically presenting as firm, glossy skin lumps that are painless, these lumps may display hues of red, pink, or blue. Characterized by rapid growth, they can pose challenges in treatment if they extend beyond the skin.


Upon a skin cancer diagnosis, your doctor may assign a stage to the tumor, indicating the necessity for further testing to assess its extent and the likelihood of spreading or recurring post-treatment. These determinants aid in selecting the most suitable therapy for your condition.

Key factors considered in skin cancer staging comprise:

  • T, representing the size of the tumor and the extent of its growth within the skin.
  • N, indicating whether the skin cancer has metastasized to lymph nodes
  • M, denoting metastasis to distant skin regions or other organs


Basal cell carcinoma, squamous cell carcinoma, and Merkel cell carcinoma are all linked to cellular damage caused by extended or chronic exposure to ultraviolet (UV) rays. Individuals with light-colored skin, prone to burning, face a higher risk, especially if they or their family members have a history of skin cancer.

To reduce the risk of skin cancer, it’s advisable to use sunscreen and wear protective clothing, while also avoiding sun exposure during peak hours (typically between 10 a.m. and 2 p.m.). Indoor tanning presents an increased risk, as tanning beds and lamps emit intense UV rays capable of damaging skin cells and contributing to cancer.

Additionally, infection with certain viruses such as specific strains of HPV and Mouse Polyomavirus (MPyV) further adds to the risk factors for developing skin cancer.