Skin Cancer: An Overview

About David Bakalov

David Bakalov is currently a senior at Beverly Hills High School where he is a member of the school’s Medical Science Academy, Teen Advisory Board, and the Speaker Series Committee. He is also a Teen Volunteer at Cedars Sinai Medical Center. David’s interest in medicine was truly explored when he entered high school and realized that he is most interested in becoming a neurosurgeon. David researched and wrote this article as part of the Medical Scholars Program through the Osborne Head and Neck Foundation.

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About Dr. Hootan Zandifar

Dr. Hootan Zandifar is board-certified in Otolaryngology and fellowship-trained in Facial Plastics and Reconstructive Surgery. Dr. Zandifar is the director of the Skin Center at the Osborne Head and Neck Institute based at Cedars-Sinai Medical Towers.

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What Is Skin Cancer?

Skin cancer is a disease that consists of an uncontrolled growth of skin cells. The condition is typically caused by mutations in skin cell DNA due to repeated exposure to ultraviolet radiation emitted from the sun. These mutations can cause cells to begin multiplying rapidly and develop into tumors.

Actinic Keratoses (AK)

Actinic Keratoses (AK) are the most common type of precancerous skin lesions. AKs are initially so miniscule that they are usually identified through touch rather than vision. Due to their scaly and crusty texture, they typically feel like sandpaper when you run your finger over them. AKs could often itch or become inflamed and even bleed in rare cases. One must also be careful when trying to diagnose them early because they may occasionally vanish but return at a later time.

AKs are precancerous and most often benign, but they should still be of concern because they indicate that your skin has experienced damage from the sun and is at a higher risk of developing other, possibly more harmful, skin cancers. If AKs are left untreated, the chance of one becoming a squamous cell carcinoma (the skin cancer most associated with AKs) increases. 

Squamous Cell Carcinoma (SCC)

Squamous cells are the uppermost cells of the epidermis (the upper layer of the skin) that are constantly shed as new cells form. Squamous cell carcinoma (SCC) is the second most common form of skin cancer. This type of cancer usually looks like a scaly patch, an open sore, or a firm red bump and is often crusty and bleeds easily if scraped. Any part of the body is prone to SCC, but the most common head and neck locations include the face, rim of the ear, neck, lower lip, and scalp. Long term exposure to ultraviolet rays over the course of one’s life is often the main cause of SCC. This includes year-round exposure and/or intense summer exposure.

Figure 1: Image of squamous cell carcinoma.


As with most other skin cancers, sites on the body that have already had a SCC tumor are more prone to developing another lesion. This increased likelihood is due to the irreversible damage from the sun that is present in that area of the body.

Basal Cell Carcinoma (BCC)

Basal cells are located in the lower part of the epidermis (the basal cell layer) and are responsible for dividing into new cells that replace the squamous cells once they shed. Basal cell carcinoma (BCC) is the most common type of skin cancer with more than 4 million cases diagnosed each year in the United States. Fortunately, BCC is also the least threatening skin cancer as it very rarely metastasizes (spreads) past the original location of the tumor. BCCs can look similar to SCCs and often resemble red patches, open sores, or firm bumps. They are also slow growing and can take many years to show up, much like SCC.

Figure 2: Image of basal cell carcinoma.


While BCC sounds relatively harmless, it should not be ignored as early treatment is often crucial. Even though BCCs rarely spread to vital organs, they still have the potential to cause notable disfigurement and sometimes even nerve or muscle damage. In addition, if the tumor is allowed to grow larger, the reconstruction procedure following surgery may require more drastic measures, such as skin grafts.


Melanocytes are the cells in the deeper layers of the skin that produce the brown pigment called melanin which serves to protect the skin from the harmful effects of sun exposure. This melanin production is why skin tends to get darker when exposed to the sun. Melanomas are the most dangerous form of skin cancer as they are most likely to grow and spread to other parts of the body. Since most melanoma cells continue to produce melanin, tumors are often black or brown although some can be tan, pink, or white. Any part of the skin is at risk for developing melanoma, but two of the most common sites are the neck and face.

Figure 3: Image of malignant melanoma.


About 10,000 Americans die annually of melanoma. Such statistics convey the importance of early recognition and treatment in order to prevent the advancement of the cancer. Since many moles on the skin can be harmless, it is important to be able to differentiate between moles that are benign (noncancerous) and malignant (cancerous). A general guideline known as the ABCDEs of melanoma covers important warning signs:

  • Asymmetrical Shape – Benign moles are symmetrical while melanoma growths are usually irregular in shape.
  • Border – Benign moles usually have smooth and defined borders while melanoma lesions are more irregular.
  • Color – Benign moles are often a single color while melanoma moles are usually multi-colored with uneven distributions.
  • Diameter – Melanomas are often about the size of a pencil eraser (>6mm) whereas benign moles are typically smaller.
  • Evolution – Noting any abnormal changes in the characteristics of a mole can often be the difference between life and death because paying close attention to your moles can allow for early diagnosis of possible skin cancers


Proper skin care and protection is crucial in preventing the potentially harmful effects of skin cancer. The following guidelines can drastically reduce the chances of developing one or more of the types of skin cancer discussed above:

  • Wear clothing that properly covers common sunburn locations. (ex: a hat and sunglasses).
  • Use sunscreen with an SPF (sun protection factor) of at least 15 and make sure to reapply the sunscreen every 2 hours when outside.
  • Avoid tanning, especially indoor UV tanning beds.
  • Examine your skin, especially the common sites, at least once a month.
  • Make sure that the sunscreen you use is broad spectrum (UVA/UVB)


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