The month of May is skin cancer awareness month so it’s a perfect time to get educated on the most common types of skin cancers and some specific characteristics of them.
What do I look for?
This is the question I consistently get when doing full-body skin exams on patients. What am I supposed to be looking for? That’s not something that’s easily answered but we do have some guidelines for personal use and to share with those that you love.
This is the most common type of skin cancer that is typically found in the head and neck region in 85% of cases but can be anywhere. Those with fair skin are more at risk with the average lifetime risk of development of BCC being 30% in Caucasians. The main risk factor is UV exposure, solar damage. UVB rays play a greater role in causing DNA damage. However, sun damage is not the only risk factor as we know there are certain individuals that develop BCC’s in non-sun exposed areas such as the genitals or breasts. Patients who undergo organ transplants tend to be at a higher risk as well. The most typical presentation is a nodular mass however there are actually five different types which include nodular, superficial, cystic, pigmented, and morphea form. The morphea form type of BCC is one of the trickiest and rarest as it can appear white or scar-like.
We typically refer to actinic keratosis as precancerous lesions. These are precancerous to Squamous Cell Carcinoma. They are typically found in sun-damaged areas such as the forearms, scalp, and face. These lesions are very superficial, once they become deeper and extend into the dermal layer we refer to them as a squamous cell. There is no way of knowing what percentage of these lesions will develop into skin cancer. It is important to treat them with liquid nitrogen or a topical chemotherapy cream to eradicate lesions. Actinic cheilitis refers to actinic damage to the lower lip. This does need to be addressed and followed closely as squamous cell carcinoma found on the lips has a higher risk of metastasis or distant spread.
This is the second most common type of skin cancer. One of the most important facts to know about squamous cell carcinoma is that they hold a much higher risk of metastasis, distant spread, than basal cell carcinoma. The risk factors for SCC’s do include UVB exposure, genetics, PUVA (light therapy treatment for Psoriasis), Arsenic, HPV types 6, 11, and 16 which are associated with warts, transplants patients. The location of SCC’s are typically found in sun-exposed areas but more so on the hands, forearms, and ears. This particular type of skin cancer usually appears as a thick scale on top of a red base.
Melanoma is a cancer of the melanocytes or pigment cells that can occur in the skin, eyes, gastrointestinal tract, brain, or mucous membranes. Melanoma has the potential to metastasize to any part of the body. The average age of onset is 57 years of age. When looking for melanoma we use the ABCDE’s rule.
Asymmetry: When checking moles are they evenly pigmented or do they have multiple colors or one side is different than the other?
Borders: Are they well circumscribed? Do the edges jut out on one side?
Color: Has the spot gotten darker? Does it match the other moles or freckles around it?
Diameter: The general rule of thumb is anything larger than 6 mm or the size of a pencil eraser. Not a hard and fast rule, melanomas definitely do not always fit the book here.
Evolution: Has the lesion changed? Anything, that has changed whether that be size, color, borders it’s important to get it checked.
There are four types of melanoma that include nodular, superficial spreading, lentigo maligna, and acral-lentiginous. It is important to note there are other variants of melanoma but they account for less than 2%.
Superficial spreading: Typically flat lesions that makeup 70% of the diagnosis of melanoma. These can be found anywhere on the body but more often on the upper back or the legs of women.
Nodular: Typically a nodule or papule that makes up 20% of the diagnosis of melanoma. Again, these can be found anywhere and are typically black or dark brown. However, there are amelanotic melanomas that can appear pink or red as they lack pigment.
Lentigo Maligna: Typically flat lesions found on the face that make up 4%-15% of all diagnosis of melanoma. These tend to grow much more slowly.
Acral-lentiginous: These appear on the palms, soles, fingers, toes, and mucous membranes. These make up 2%-8% of all melanomas in whites however these comprise 30%-75% of melanomas in blacks, Asians, and Hispanics.
Written by Patricia Spitzer, PA-C. Patricia is one of our board-certified mid-level practitioners specializing in dermatology. Patricia has a bachelor’s degree in Psychology from the University of Central Florida. She received her master’s degree in Physician Assistant studies at Nova Southeastern University. Patricia has over 8 years of experience in dermatology.