Categories
Cancers

Skin Cancer

Skin cancer is an abnormal cancerous growth in the skin. These types of cancers develop from the mutation of normal cells into cancerous cell that have the ability to spread to other parts of the body.

Types of skin cancer
3 typical types of skin cancers are squamous cell carcinoma, basal cell carcinoma and melanoma. Image courtesy of Mayo Clinic

There are 2 main types of skin cancers:

  • Nonmelenoma Skin Cancer – These types of cancers refer to all types of skin cancers that are no melanoma. The most common types are squamous cell carcinoma and basal cell carcinoma.
  • Melanoma Skin Cancer – A type of cancer that starts in the melanocytes of the skin. Melanocytes are the cells that produce melanin, this is the brown pigment that gives us a golden brown tan when sitting on the beach in Cabo San Lucas.

A vast majority of all skin cancers will form in the upper most layer of the skin, this layer is called the epidermis. There are 3 main types of cells in the epidermis:

  1. Squamous Cells – These cells are located in the outer most layer of the epidermis and are flat like little mini pancakes. They are constantly being shed at the outermost layer to make room for new cells forming underneath.
  2. Basal Cells – These cells are located in the lower part of the epidermis which forms the border between the dermis and the epidermis. Basal cells are constantly replicating themselves to replace squamous cells being shed at the surface of the epidermis. After being replicated in the lower layer of the epidermis, basal cells move up the epidermis, and eventually flatten to become squamous cells that will eventually make up the outer layer of the epidermis.
  3. Melanocytes – These cells make the brown pigment called melanin. This is thee pigment that gives tanned skin its brown color. Melanin protects the lower layer of skin from the harmful effects of the sun.
Diagram illustrating the location of squamous and basal cells as well as the melanocytes.

Squamous Cell Carcinoma (Nonmelinoma skin cancer)

This is the second most common form of skin cancer. It is typically found on areas of the body with high exposure to the sun. This includes the head, back of neck, shoulders, upper back, ears, face, arms, legs and hands. Squamous cell carcinoma is a particularly slow growing skin cancer.

Before it metastasizes to near-by tissue, it is relatively easy to treat. Unlike other skin cancers it can easily spread to near by tissues such as organs, bone and the lymphatic system.

Squamous Cell Carcinoma: Risk Factors

  • Male
  • Old Age
  • Fair Skin
  • Light colored eyes
  • Blonde or red hair
  • Prolonged exposure to direct sunlight
  • Prolonged exposure to tanning beds and bulbs
  • Prolonged exposure to arsenic
  • Immune disease such as HIV / AIDS
  • Radiation exposure
  • Genetic factors

Squamous Cell Carcinoma: Symptoms

Squamous cell carcinoma normally starts with a small bump and / or a red scaly patch of skin. This area normally gets crusty and can easily bleed if scratched. Smaller growths typically are painless while larger growths could be itchy or painful to the touch. Any changes in the skin should immediately be reported to your doctor.

Squamous Cell Carcinoma: Diagnosis

Your doctor will check your medical history as well about your sun exposure, as well as other symptoms you might be having. Your doctor will then examine the size, shape and color of the growth.

The doctor will also look for other similar growths and check your lymph nodes to make sure they aren’t bigger or harder than normal.

After the physical examination, if your doctor determines that it is questionable, he will order a skin biopsy, where a small piece of the growth is removed. This biopsy is sent to a laboratory for testing to determine if it is indeed a squamous cell carcinoma.

Basal cell carcinoma (Nonmelinoma skin cancer)

Basal cell carcinoma is also typical on areas of the body with higher levels of exposure to the sun. As the name indicates basal cell carcinoma originates in the basal cells. Basal cells are found at the border of the dermis and epidermis.

Basal Cell Carcinoma: Risk Factors

  • Male
  • Old Age
  • Fair Skin
  • Light colored eyes
  • Blonde or red hair
  • Prolonged exposure to direct sunlight
  • Prolonged exposure to tanning beds and bulbs
  • Prolonged exposure to arsenic
  • Immune disease such as HIV / AIDS
  • Exposure to immune suppressing drugs
  • Radiation exposure
  • Genetic factors

Basal Cell Carcinoma: Symptoms

  • A white or skin colored bump that appears to be transparent or translucent, so much in fact that you can see tissue and blood vessels through the surface of the skin under the bump. In people of darker skin color the bump also will be darker, but still could be translucent. These bumps could have lesions and could even be scabbed over. They are most commonly found on the face and ears.
  • A flat reddish lesion also with raised edges on the back and / or chest. As time goes on, this patch can grow quite large and become depressed as opposed to raised.
  • A white scare-like waxy lesion without obvious edges. These are quite uncommon.
  • A black, blue or brown lesion – also with a translucent and / or raised edge.

Basal Cell Carcinoma: Diagnosis

Your doctor will check your medical history and give you a physical. He might ask you when you noticed the lesion? Have you ever had skin cancer before? Has anyone in your family had skin cancer? Are there any other growths on your body? Any changes that you have noticed to lesion in terms of size and color? Is the lesion painful? Your doctor might inquire about sun exposure, sun block, tanning beds, etc.

Then after the normal questionnaire the doctor might give you a visual skin exam. He will check your skin looking for lesions fitting the description of basal cell carcinoma.

Ultimately if the doctor feels that the doctor feels based on the physical examination and your medical history that he suspects your lesion might be basal cell carcinoma, he or she will ultimately take a biopsy of the lesion to test it in a laboratory to make a final determination.

Melenoma

Also known as malignant melenoma, is a type of cancer that develops from the melanocytes. Melanocytes are the pigment producing cells in the skin that produce melanin, which is what gives tanned skin its dark color after sun exposure. Melanoma is considered to be the most dangerous of all the skin cancers.

Melanoma: Risk Factors

  • Male
  • Old Age
  • Fair Skin
  • Light colored eyes
  • Blonde or red hair
  • Prolonged exposure to direct sunlight
  • Prolonged exposure to tanning beds and bulbs
  • Living close to the equator
  • Living at a higher altitude
  • Immune disease such as HIV / AIDS
  • Exposure to immune suppressing drugs
  • Genetic factors

Melanoma: Symptoms (provided by Mayo Clinic)

  • A change in an existing mole
  • The development of a new pigmented or unusual-looking growth on your skin

Unusual modes could be a sign of melanoma (also provided by Mayo Clinic)

  • A is for asymmetrical shape. Look for moles with irregular shapes, such as two very different-looking halves.
  • B is for irregular border. Look for moles with irregular, notched or scalloped borders — characteristics of melanomas.
  • C is for changes in color. Look for growths that have many colors or an uneven distribution of color.
  • D is for diameter. Look for new growth in amole larger than 1/4 inch (about 6 millimeters).
  • E is for evolving. Look for changes over time, such as a mole that grows in size or that changes color or shape. Moles may also evolve to develop new signs and symptoms, such as new itchiness or bleeding.

Melanoma: Diagnosis

As with other skin cancers your doctor will start by checking your medical history and ask you a series of questions and then will be able to help determine any risk factors including environment and genetic.

However, since melanoma can pop up in places with minimal sun exposure, there are other unknown risk factors that make melanomas very dangerous.

Like other cancers, ultimately a biopsy is needed to confirm a melanoma.

CONCLUSION

Skin cancer is the most common type of cancer in the world. According to the American Cancer Society, in the US alone it is estimated that 5.4 million skin cancer cases are diagnosed each year. The survival rate of most skin cancer is extremely high if caught early, however in most cases we believe that by making good choices about sun exposure and diet, you can mitigate this risk.