From Basal to Melanoma: A Closer Look at Types of Skin Cancer

Skin cancer, one of the most prevalent forms of cancer globally, arises when the skin cells undergo malignant transformations. With over 5 million cases diagnosed each year in the United States alone, skin cancer demands our attention and understanding. There are several types of skin cancer, each with distinct characteristics, risk factors, and treatment approaches, so read on to learn about them and how to identify cancerous moles.

Basal Cell Carcinoma (BCC)

Basal cell carcinoma is the most common type of skin cancer, accounting for approximately 80% of all skin cancer cases. While it is considered the least aggressive, it is crucial to recognize and treat BCC promptly to prevent it from causing significant damage.

Characteristics:

• BCC typically appears as a shiny, pearly bump or a flesh-coloured, flat lesion.
• Skin cancer spots often develop on sun-exposed areas such as the face, neck, or hands.
• Slow growth is a hallmark of basal cell carcinoma, and it rarely spreads to other parts of the body.

Causes and Risk Factors:

• Prolonged exposure to ultraviolet (UV) radiation from the sun or tanning beds is a primary risk factor for BCC.
• Fair-skinned individuals with a history of sunburns, those with a weakened immune system, and individuals with a family history of skin cancer are at an increased risk.

Treatment:

• Surgical excision is the most common and effective treatment for BCC.
• Other options include Mohs surgery, cryotherapy, and topical medications.

Squamous Cell Carcinoma (SCC)

Squamous cell carcinoma is the second most common type of skin cancer, accounting for about 20% of cases. While it is more aggressive than basal cell carcinoma, detection and treatment can be highly effective in early stage skin cancer.

Characteristics:

• SCC often presents as a red, scaly patch or a firm, raised nodule.
• It may develop in areas frequently exposed to the sun, such as the face, ears, and hands.
• Unlike BCC, squamous cell carcinoma has a higher propensity to metastasize if left untreated.

Causes and Risk Factors:

• Cumulative sun exposure and the use of tanning beds are significant contributors to SCC.
• Immunosuppression, chronic skin inflammation, and exposure to certain chemicals also increase the risk.

Treatment:

• Surgical removal is the primary treatment for SCC.
• In some cases, radiation therapy or topical medications may be recommended.

Melanoma

Melanoma cancer, though less common than basal cell and squamous cell carcinoma, is the most aggressive form of skin cancer. It originates in the melanocytes, the pigment-producing cells responsible for skin colour.

Characteristics:

• Melanoma often appears as an asymmetrical, irregularly bordered, multicoloured lesion with a diameter larger than a pencil eraser.
• It can occur anywhere on the body, even in areas not exposed to the sun.
• Melanoma has a higher likelihood of metastasising to other organs, making early detection crucial.

Causes and Risk Factors:

• Intense and intermittent sun exposure, especially leading to sunburns, increases the risk of melanoma cancer.
• Individuals with fair skin, a history of blistering sunburns, a large number of moles, or a family history of melanoma are at a higher risk.
• Genetic factors and a weakened immune system also contribute to susceptibility.

Treatment:

• Surgical excision is the primary treatment for early stage  cancer.
• Advanced cases may require additional therapies such as immunotherapy, targeted therapy, chemotherapy, or radiation.

The ABCDEs of Melanoma Detection

To aid in the early identification of melanoma and the stages of melanoma skin cancer, healthcare professionals and individuals can follow the ABCDE rule:

• A: Asymmetry – One half of the mole or spot does not match the other half.
• B: Border irregularity – The edges are uneven, notched, or blurred.
• C: Colour – The colour is not uniform and may include shades of brown, black, blue, or red.
• D: Diameter – The lesion is larger than 6 millimetres (the size of a pencil eraser) or is growing in size.
• E: Evolving – The mole is changing in size, shape, or colour.

Merkel cell carcinoma (MCC)

Merkel cell cancer or carcinoma (MCC) is a rare but aggressive type of skin cancer that typically develops in the Merkel cells, which are located at the base of the epidermis, the outermost layer of the skin.

Characteristics:

• Merkel cell cancer is known for its aggressive behaviour. It can grow rapidly and has a higher likelihood of spreading (metastasizing) to other parts of the body compared to some more common types of skin cancer.
• Merkel cell cancer often appears as a firm, painless, flesh-coloured or bluish-red nodule on the skin. It can be similar in appearance to other types of skin cancer or benign skin conditions, making it important to have any unusual growth or lesion evaluated by a healthcare professional.

Causes and Risk Factors:

• The primary risk factor for Merkel cell cancer is exposure to ultraviolet (UV) radiation, such as from sunlight.
• Other risk factors include having a weakened immune system (e.g. due to conditions like HIV or organ transplantation) and being older, as the incidence of Merkel cell cancer increases with age.

Treatment:

• Surgical removal of the tumour is often the primary treatment for Merkel cell cancer. This may involve removing the tumour along with a margin of healthy tissue.
• Radiation therapy may be used to target and destroy cancer cells. It is often recommended to reduce the risk of recurrence or if the cancer has spread to nearby lymph nodes.
• In some cases, chemotherapy drugs may be prescribed to kill early stage cancer cells or slow their growth.
• More recently, immunotherapy has shown promise in the treatment of Merkel cell cancer. This involves using drugs that stimulate the body’s immune system to recognise and attack cancer cells.

Prevention and Early Detection

Preventing skin cancer is closely tied to sun protection practices. This includes:

Sunscreen: Regular use of a broad-spectrum sunscreen with an SPF of 30 or higher, applied generously and frequently.

Protective Clothing: Wearing long-sleeved shirts, wide-brimmed hats, and sunglasses to shield the skin from UV radiation.

Avoiding Tanning Beds: The use of tanning beds increases the risk of skin cancer spots and should be avoided.

Regular Skin Checks: Conducting monthly self-examinations and seeking professional dermatological assessments for any suspicious changes in moles or skin lesions.

Conclusion

Understanding the different types of skin cancer is paramount for effective prevention, early detection, and timely treatment. Basal cell carcinoma, squamous cell carcinoma, and melanoma each present unique challenges, but with awareness and proactive measures, individuals can significantly reduce their risk. Practising sun safety, regular skin self-examinations, and seeking professional medical advice for concerning changes are essential steps in promoting skin health and minimising the impact of skin cancer on one’s life. By fostering a culture of awareness and prioritising skin care, we can collectively work towards reducing the prevalence and impact of skin cancer on a global scale.

For more information, find your nearest Dermatologist