National Healthy Skin Month - Skin Cancers

Did you know that November is the National Month for healthy skin? Your skin is the largest organ in the body and it reveals a lot about our own health. It's only natural that we should pay attention to our own skin!

National Healthy Skin Month is aimed at helping people understand how to take better care of their own skin as well as offer useful tips in checking your skin periodically for skin cancer. Skin cancer is basically mutated skin cells with uncontrolled proliferation. There are essentially two categories of skin cancer, melanoma vs non-melanoma (basal cell carcinoma and squamous cell carcinoma) skin cancers. (1) These two topics will be discussed further below.

Risk factors (2, 3)

• Individuals with fair skin (Fitzpatrick skin phototype I, II or III) and albinism.

• Individuals with coloured skin are at risk of developing acral lentiginous melanoma

• Family history of skin cancer

• Skin that is easily burnt or having history of sunburn.

• Increasing age

Causes

The DNA located in our skin cells are susceptible to damage by ultraviolet light and the cumulative effect can occur over years before cancer develops. A few common causes: (2, 3)

• Sun exposure, use of tanning beds

• Smoking

• Weakened immune system such as bone marrow transplant, kidney transplant, HIV, AIDS or any autoimmune disease such as inflammatory bowel disease

• Certain occupations with prolonged sun exposure including farm workers, gardeners and building site workers

Clinical Features

Typically appears as either a progressive lump, nodule, ulcer or changing lesion in terms of colour, shape and size. These lesions if untreated, can lead to further ulceration, bleeding and local invasion of adjacent tissues or distant spread (metastasis). (4)

Skin cancers are commonly diagnosed by dermatologists through clinical findings using a Dermoscope or through a skin biopsy. (3)

Non-melanoma Skin Cancers

Basal Cell Carcinoma (BCC)

Basal cell carcinoma can be differentiated into four subtypes: (6)

1. Nodular Basal cell carcinoma

2. Superficial Basal cell carcinoma

3. Morphoeic Basal cell carcinoma

4. Basosquamous carcinoma

Figure 1: Nodular Basal cell carcinoma (6)

Features of Nodular BCC

• Most common BCC subtype

• Highest incidence in middle aged and elderly population, with males more commonly affected than females

• Painless and slow growing in nature

• Characteristically displays evidence of pearly translucent rolled edges with central ulceration

• Telangiectasia can be appreciated

• Very rarely a threat but can be locally invasive if neglected

Figure 2: Superficial Basal cell carcinoma (6)

Features of Superficial BCC

• More commonly seen in younger adults, occurring on areas such as upper trunk and shoulders

• Slightly scaly with irregular patches and plaques

• Thin and translucent, rolled borders

Figure 3: Morphoeic Basal cell carcinoma (6)

Features of Morphoeic BCC

• Waxy scar-like plaque with indistinct borders

Figure 4: Basosquamous carcinoma (6)

Features of Basosquamous carcinoma

• Features of both nodular basal cell carcinoma and squamous cell carcinoma

Management

• Referral to dermatology

• Non-surgical interventions: Imiquimod or fluorouracil cream

• Cryotherapy

• Mohs microscopic surgery for optimal cosmetic outcome

Squamous Cell Carcinoma (SCC)

SCCs are less common than BCCs but poses a greater threat in comparison as they are usually more aggressive and grows much quicker. (7) May derive from precursor lesions such as actinic keratoses and Bowen's disease. (7)

Figure 5: Squamous cell carcinoma (7)

Features of SCC

• Scaly keratinous plaques

• May be orange-red or brown in colour

• Most commonly occurs on sun-exposed sites of the body

Management (4)

• 2 week referral pathway to dermatology

• Shaving, curettage and electrocautery for low risk lesions

• Cryotherapy if the lesion is small

• Mohs microscopic surgery for larger facial lesions for optimal cosmetic outcome

• For advanced or metastatic SCC, treatment of choice includes surgery, radiotherapy and targeted therapy such as epidermal growth factor receptor inhibitors

Melanoma Skin Cancers

Derived from pigment producing dendritic cells found in the basal layer of the epidermis called melanocytes. (8) It is the most serious form of skin cancer which causes death in younger to middle aged population with high incidence of metastasis. (8)

Figure 6: Superficial spreading melanoma (8)

Melanoma can be differentiated into various subtypes:

Figure 7: Melanoma Subtypes (9)

Nodular Melanoma

Figure 7: Nodular Malignant Melanoma in it's vertical growing phase. Appearance is scaly and rapidly enlarging. (8)

Lentigo Maligna

Figure 8: Lentigo Maligna, more commonly seen in elderly due to cumulative sun damage across the years (10)

Figure 9: Acral Lentiginous melanoma, irregular pigmented longitudinal bands in the nail (8)

Management (8)

• Surgery – Wide local excision depending on Breslow thickness

• Radiotherapy

• Systemic therapy if widespread disease including immunotherapy or targeted therapy

Prevention

Prevention of all skin cancers revolve around the concept of reducing any form of sun exposure. Patients are recommended to:

• Stay indoors and under shaded areas

• Wear covered clothing

• Apply sunscreen with SPF 50+

• Avoid indoor tanning such as tanning beds

As winter is approaching, it is a good time to carefully check for any new spots that seems unusual in shape, colour and size. People of darker complexion are not exempted from skin cancers and often can be quite difficult to identify. Take this opportunity to give your skin some tender loving care it deserves!

References

1. National healthy skin month [Internet]. 2023. Available from: https://nationaltoday.com/national-healthy-skin-month

2. What are the risk factors for skin cancer? [Internet]. Centers for Disease Control and Prevention; 2023. Available from: https://www.cdc.gov/cancer/skin/basic_info/risk_factors.htm

3. Skin cancer [Internet]. Available from: https://dermnetnz.org/topics/skin-cancer

4. Dermsoc Dundee Revision Slides

5. Risks and causes of skin cancer [Internet]. 2023. Available from: https://www.cancerresearchuk.org/about-cancer/skin-cancer/risks-causes

6. Basal cell carcinoma [Internet]. Available from: https://dermnetnz.org/topics/basal-cell-carcinoma

7. Cutaneous squamous cell carcinoma [Internet]. Available from: https://dermnetnz.org/topics/cutaneous-squamous-cell-carcinoma

8. Melanoma [Internet]. Available from: https://dermnetnz.org/topics/melanoma

9. Malignant Melanoma [Internet]. Available from: https://www.passmedicine.com/v7/menu.php

10. Lentigo Maligna [Internet]. Available from: https://www.aocd.org/page/LentigoMaligna