From the Guidelines
No, squamous cell skin cancer is not the same as basal cell skin cancer. These are two distinct types of non-melanoma skin cancers that differ in their origin, appearance, behavior, and treatment approaches. Basal cell carcinoma (BCC) develops from the basal cells in the lowest layer of the epidermis and is the most common form of skin cancer, typically growing slowly and rarely spreading to other parts of the body. Squamous cell carcinoma (SCC) originates from the flat, scale-like cells that make up the outer layer of the skin and is the second most common type of skin cancer. SCC tends to be more aggressive than BCC and has a higher likelihood of spreading to other areas of the body if left untreated. According to the guidelines of care for the management of cutaneous squamous cell carcinoma 1, the treatment approach for high-risk cSCC, such as those with high-risk factors, may involve Mohs surgery (MMS), which has shown lower recurrence rates compared to standard excision and other non-MMS treatment modalities.
Key differences between BCC and SCC
- Origin: BCC develops from basal cells, while SCC originates from squamous cells
- Appearance: BCC typically appears as a shiny, pink or red bump, while SCC often appears as a firm, red nodule or a flat sore with a scaly crust
- Behavior: BCC tends to grow slowly and rarely spreads, while SCC is more aggressive and has a higher likelihood of spreading to other areas of the body
- Treatment: Both cancers may be treated with surgical removal, radiation therapy, topical medications, or other specialized treatments, but the approach may differ depending on the size, location, and stage of the cancer
Treatment options for high-risk cSCC
- Mohs surgery (MMS): a surgical procedure that involves removing the cancerous tissue layer by layer, with each layer examined under a microscope until all cancerous cells are removed
- Standard excision: a surgical procedure that involves removing the cancerous tissue and a margin of healthy tissue around it
- Radiation therapy: a treatment that uses high-energy rays to kill cancer cells
- Topical medications: creams or ointments applied directly to the skin to treat the cancer
The guidelines recommend MMS for the treatment of high-risk cSCC, based on the best available data 1. This recommendation is supported by studies that have shown lower recurrence rates for MMS compared to standard excision and other non-MMS treatment modalities.
From the Research
Differences between Squamous Cell and Basal Cell Skin Cancer
- Squamous cell carcinoma (SCC) and basal cell carcinoma (BCC) are two types of nonmelanoma skin cancers (NMSCs) 2.
- BCC comprises approximately 80% of NMSCs, while most of the remainder are cutaneous squamous cell carcinomas (SCCs) 2.
- The predominant risk factor for NMSC is exposure to solar UV radiation, and skin type also plays a role, with a higher incidence of NMSCs among fairer-skinned individuals 2.
Treatment Options
- Treatment options for BCC and SCC include surgical techniques such as excision, curettage and electrodessication, and Mohs micrographic surgery 2.
- Nonsurgical therapies such as topical therapy or photodynamic therapy may be used for BCC lesions if surgical techniques are not appropriate 2.
- Radiation therapy (RT) can be used as a definitive or postoperative treatment for BCC and SCC, with recommendations based on a systematic literature review and consensus-building methodology 3.
Prognosis and Prevention
- The prognosis for patients with NMSC is extremely favorable, with a low risk of metastasis and significant morbidity or mortality being rare 2.
- Primary interventions for prevention include counseling on reducing sun exposure, use of UV-protective clothing and sunscreen, and discouragement of tanning bed use 2.
- The American Academy of Dermatology recommends skin examinations for all patients with NMSC at least annually 2.
Comparison of SCC and BCC
- While both SCC and BCC are types of NMSC, they have different characteristics and risk factors, with SCC being more aggressive and having a higher risk of metastasis 4, 5.
- Radiation treatment, particularly if experienced before age 20, seems to increase the long-term risk of both basal and squamous cell carcinomas of the skin, with different risks depending on sun exposure or host response to sunlight exposure 5.