Skin cancer screening: Clinical sciences

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Introduction0:00–0:58

Skin cancer is one of the most common cancers in the United States. It is estimated one in five individuals will develop some form of skin cancer within their lifetime.
So, prevention is the most important way to limit the risk of developing skin cancer. Some of the most effective preventative methods include decreasing exposure to UV rays from sunlight by wearing sun-protective clothing and using broad spectrum waterproof sunscreen with an SPF of 30 or higher, as well as avoiding artificial UV rays like tanning beds.
Because complete avoidance of UV rays is are not feasible, regular skin cancer screenings, which include risk factors assessments and skin exams, are used to identify individuals more susceptible for developing skin cancer.
Alright, when a patient presents for a skin cancer screening, the initial step is to assess their risk factors for future skin cancer.

History and Physical0:58–1:52

Individuals at an increased risk for developing skin cancer include those who are older than 50 years; as well as sun-sensitive individuals with red or blonde hair, light eye color, light skin pigmentation, or freckling.
Other important risk factors include a nevi count that is greater than 50 with or without large, atypical nevi; as well as personal or family history of skin cancer; and immunosuppression or chronic immunosuppressive therapy.
Lastly, there’s an increased risk for skin cancer in patients with certain syndromes and genetic disorders, such as xeroderma pigmentosum or albinism.

No risk factors1:52–2:20

Now, if your patient does not have any of the risk factors mentioned above, then they are considered to be at low risk of developing skin cancer and no routine screening examination is recommended.
Keep in mind, however, any suspicious skin lesions on these patients should be checked regularly by their primary care physicians or evaluated by a dermatologist.
On the other hand, if your patient has any of the risk factors mentioned previously, they are considered to be at a high risk for developing skin cancer.

Risk factors present2:20–4:10

These individuals should undergo annual screenings, which include a total body skin examination with a source of bright light and a magnifying lens.
Trained physicians may also use a dermatoscope, which is a tool that can magnify skin lesions and emit a special light to help detect features that are not visible to the naked eye.
For example, a dermatoscope can show you subsurface skin structures within the epidermis, dermoepidermal junction and the papillary dermis.
Visualizing these structures can increase the diagnostic accuracy of suspicious lesions. Now, let’s talk about the physical examination.
During the total body skin exam, the scalp, face, head, neck, arms, hands, and axillae are assessed for any lesions. Make sure to examine your patient in the supine position while inspecting the chest, abdomen, lower extremities, and toe webs; and prone position when evaluating the back, buttocks, lower extremities, and soles of the feet.
Keep in mind that most skin cancers develop in areas typically exposed to UV rays, especially the scalp, face, trunk, and extremities; however, don’t forget that certain skin cancers may develop in atypical areas, such as subungual melanoma in the nail bed, so be sure to check there too!Let’s go over some benign lesions first.

Benign lesions4:10–4:49

A very common benign lesion you may find is seborrheic keratosis, which presents as a dull, verrucous, and well-demarcated lesion, typically in a shade of brown, and is often described as a stuck-on appearance.
Other benign lesions include solar lentigo, also known as liver spots, which are hyperpigmented, flat patches of an even brown shade.
Cherry angiomas, which are capillary proliferations, red or purple color, and often dome-shaped are also quite common.Now let’s go over some malignant lesions.

Malignant lesions4:49–6:26

The most common skin cancer is basal cell carcinoma, which typically presents as a flesh-colored, pearly papule, often with telangiectatic vessels, and some may also have ulceration.
The second most common skin cancer is cutaneous squamous cell carcinoma, which typically presents as an erythematous plaque that can be scaly, crusted, or ulcerated.
Lastly, when evaluating melanocytic nevi, commonly known as moles, during your exam, you can use the ABCDE rule of melanoma to identify any suspicious characteristics.
This rule refers to the asymmetry, border, color, diameter, and evolution in time. A normal-appearing mole is typically symmetrical; with even borders; consists of one single color; is usually smaller than 6 millimeters in diameter; and will not change or evolve over time.
On the other hand, a suspicious mole can appear asymmetrical; with uneven and irregular borders; often with multiple colors, typically different shades of brown or black, but may even have red, white, or blue areas; the diameter could be larger than 6 millimeters in size; and may evolve over time, so you may notice any change in the lesion compared to the last exam.
If you identify a suspicious mole during your exam, then the patient should be referred to a dermatologist for further evaluation.
Alright, as a recap… Skin cancer screening is an important part of skin cancer prevention and involves identification and assessment of the patient’s risk factors.

Review6:26–6:57

Patients with any one of the risk factors are considered high risk for developing skin cancer and should undergo annual screenings, which will include a total body skin examination with a source of bright light and a magnifying lens, or using a dermatoscope, looking for any potentially benign or malignant lesions, as well as an assessment of moles with the ABCDE