Introduction to Skin Cancer


Skin cancer is extremely common, so common that it’s the most common type of cancer. Without further ado, here is an introduction to skin cancer.

The statistics are scary. It’s more common than breast, prostate, and lung cancer combined. According to the Skin Cancer Foundation, 5 million people are treated for skin cancer every year in the U.S. alone. Think it won’t happen to you? Well if 1 in 5 people develop skin cancer in their lifetime, and you know more than 5 people, then either you or someone close to you will have skin cancer in their lifetime.

Is it most likely to be a scare from the dermatologist that results in a small biopsy and maybe some local excision? Yes.

But you could also be one of the 1 in 50 who gets diagnosed with melanoma.

What are the types of skin cancer?

There are three types of skin cancer that are subdivided into non-melanoma and melanoma skin cancer. Non-melanoma skin cancers include basal cell carcinoma and squamous cell carcinoma. Melanoma is the deadliest of the three, but fortunately the least common.

Basal Cell Carcinoma

Basal cell carcinoma starts from mutated cells at the bottom of the epidermis of your skin; that’s why they’re called basal cells. These are almost never fatal, but if you allow them to grow indefinitely they can disfigure you. If we know each other, just ask me to show you the picture of a basal cell carcinoma that destroyed a man’s face and half his skull. You can find some equally horrifying pictures on Google.

Did I mention that I’m a big fan of scare tactics?

Basal-cell-carcinoma

Basal Cell Carcinoma

Squamous Cell Carcinoma

Squamous cell carcinoma can actually start from actinic keratosis (we call them AKs). Squamous cell carcinoma is composed of abnormal squamous cells, the cells that make up most of your epidermis. If you’ve had an AK in the past, you’ve probably had your doctor freeze them off. AKs can develop into squamous cell skin cancers, or squamous cells cancers develop on their own. This cancer is more deadly than basal cell (2% of patients died from this in 2012), but not as deadly as melanoma.

squamous cell carcinoma

Squamous Cell Carcinoma

Melanoma

Melanoma is the most feared cancer of the three with good reason. It is a cancer of melanocytes, the pigment producing cells of the skin. It causes the most deaths. It’s highly resistant to treatment if found at an advanced stage. It metastasizes to the strangest places (including the heart and brain). Young people (those aged 25-29) get melanoma more often than any other type of cancer. It is slightly more common in men. If found early, melanoma is treated like any other skin cancer with simple excision. This is why daily SPF, awareness, and the total body skin exam both at home and with your dermatologist are so important.

melanoma

Melanoma

How do you get skin cancer?

It’d be great if I could say “Easy just avoid any and all sunlight from the time you were a baby until the time you die.” However, that’s an extreme solution and it’s not only sun exposure that bumps up your risk for developing skin cancer. Sun exposure is the number one avoidable risk factor. You can’t change things like family history or your natural skin color, but knowing your risk beforehand can help you be more careful and aware. 90% of basal cell and squamous cell cancers can be traced to UV exposure. 86% of melanomas can be linked to UV exposure.

Skin Color is an Important Risk Factor

Your skin color can up your risk of skin cancer significantly. Whereas only 4 in 100,000 Hispanics will develop melanoma, 25 in 100,000 of non-Hispanic Whites will. Whites have much less melanin in their skin so the energy from the sun can wreak more havoc on their cells. Melanin works to absorb those harmful UV rays.

Think you’re free and clear because your skin is dark? If you happen to get melanoma and you’re Black, you’re looking at a 75% 5-year survival rate versus 93% for Whites. Minorities are more likely to be diagnosed with late stage melanomas.

How do you treat skin cancer?

Your doctor will first do a skin biopsy to identify what the suspicious skin lesion could be and figure out if it needs to be excised. If it’s not melanoma and the cancer isn’t very extensive, the cure is simple excision and curettage (the doctors uses a really hot electricity pencil looking thing to burn the blood vessels and stop the bleeding). If you’ve got a small basal cell, the biopsy itself may be the treatment you needed. If the biopsy shows clear borders without cancer attached to your skin, you should count yourself as very lucky. You’re cured! If the biopsy shows that cancer is still present in the margins of the lesion, you will need to return to your doctor for further

Treatment of Small Skin Cancers

If you’ve got a small basal cell, the biopsy itself may be the treatment you needed. If the biopsy shows clear borders without cancer attached to your skin, you should count yourself as very lucky. You’re cured! If the biopsy shows that cancer is still present in the margins of the lesion, you will need to return to your doctor for further

If the biopsy shows that cancer is still present in the margins of the lesion, you will need to return to your doctor for further excision and wider margins. Sometimes the cancer is too big and wide for the doctor to be able to remove it without major surgery or disfiguring results. In that case some medications such as 5-fluorouracil or imiquimod can be used to topically treat the cancer. This will shrink it or treat it completely. If the goal is to shrink the cancer, once it’s small enough your dermatologist will excise it completely.

Sometimes the cancer is too big and wide for the doctor to be able to remove it without major surgery or disfiguring results. In that case some medications such as 5-fluorouracil or imiquimod can be used to topically treat the cancer. This will shrink it or treat it completely. If the goal is to shrink the cancer, once it’s small enough your dermatologist will excise it completely.

Treatment of Melanoma

If the biopsy happens to show melanoma, the pathologist will measure the depth of invasion and determine whether the excision removed all of the cancer. Once melanoma has infiltrated to a certain level of the skin, you will need a more extensive workup. Your doctor will look for nearby lymph nodes where cancer may have spread (using a sentinel lymph node biopsy) or a PET or CT scan to look for metastases. Metastatic melanoma requires systemic treatment.

Did you enjoy this introduction to skin cancer? If you have any more questions, ask away in the comments!

References

  1. http://www.skincancer.org/skin-cancer-information/skin-cancer-facts#general