Monday, December 14, 2009

Skin Cancer: More than Skin Deep – an Article Review

It’s winter so why think about skin cancer?   One of the major risk factors is UVA and UVB rays from sun exposure which is much more common in the summer.  Tanning beds never cease being used, regardless of season and may even be used more in the winter than summer.

There is never a wrong season to be reminded of the prevalence of skin cancer or the risk factors for skin cancer or ways to prevent skin cancer.

Having read this short article (full reference below) in the “throw away” December issue of the journal Advances in Skin & Wound Care it seemed a good time to again discuss skin cancer.  The article is a good overview of skin cancer which is the most common carcinoma in the United States.  The article quotes statistics from the American Cancer Society:

Statistics show that 1 in 5 Americans and 1  in 3 whites will develop skin cancer in their lifetime; 1 person dies of melanoma almost every hour.

The American Cancer Society (ACS) predicted an excess of 1.1 million new cases of cutaneous malignancy ending in 11,200 deaths in 2008.

The ACS predicted 62,480 new melanoma cases diagnosed in the United States in 2008, resulting in 8420 deaths.

The article gives a brief overview of skin changes seen with Actinic keratoses (AKs), basal cell carcinoma (BCC), squamous cell carcinoma (SCC), and malignant melanoma (MM).

Actinic keratoses are precancerous or precursor lesions to 10% of SCCs.

Scaly lesions on sun-exposed skin that do not respond to moisturizers, itch, or bleed with minimal provocation need medical attention. The length of time for an AK to progress to an SCC can be as early as 24.6 months.

Basal cell carcinoma (BCC) represents 65% to 75% of all skin cancers.  Most occur on sun-exposed parts of the face, ears, scalp, shoulders, and back.   Intense short-term UVB exposure is important in the formation of BCC.

Clinical features include pearly translucent flesh-colored papules or nodules with superficial telangiectasias (broken blood vessels). More active lesions may have rolled edges or ulcerated centers.

Squamous cell carconoma (SSC) represent 30% to 65% of all cutaneous malignancies.  SCCs are most attributable to UVB exposure, long-term or accumulative exposure over years.

Clinical features include crusted papules and plaques that may become indurated, nodular, or ulcerated. SCC may arise in chronic wounds, scars, and leg ulcers.  Recurrent SCC development within 3 years is 18%, a 10-fold higher incidence compared with initial SCC diagnosis in the general population.

Malignant melanoma (MM) represents the most serious of all cutaneous malignancies.  It is estimated that approximately 65% to 90% are caused by UV exposure, predominantly UVA.  Roughly 10% of all melanoma cases are strictly hereditary.

The ABCD rule outlines the clinical presentation and warning signals of the most common type of melanoma.

"A" is for asymmetry (one-half of the mole does not match the other half);

"B" is for border irregularity (the edges are ragged, notched, or blurred);

"C" is for color (the pigmentation is not uniform, with variable degrees of tan, brown, or black);

"D" is for diameter greater than 6 mm (about the size of a pencil eraser).

Some clinicians now include "E" regarding evolution, elevation, or enlargement of a lesion

The article very briefly touches on management, but devotes more space to prevention and need for continued education of the public.

A key determinant of skin cancer in adulthood is the exposure to UV as a child. Sun protection messages should be linked with other health promotion messages targeting children

Prevention Tips:

  • Children should be taught the correct use of sunscreen.
  • Select a product that contains the highest allowable percentage of zinc oxide (25%) and titanium dioxide (25%). Both do not undergo significant chemical change or photodegradation with exposure to UV light. Avobenzone (3%) is the only truly effective UVA absorber available and offers the greatest photostability.
  • Sunscreen should be applied to all exposed skin at least 20 minutes before going into the sun, even if it is cloudy outside, and needs to be reapplied every 2 to 3 hours or more frequently if swimming or exercising.
  • Use at least 1 oz per application, roughly equivalent to the volume of a shot glass.
  • Everyone needs to wear a hat and sunglasses with 99% to 100% UVA absorption.
  • Patients should be instructed to avoid exposure between the hours of 10 AM and 4 PM when the sun is the strongest, wear sun-protective clothing, and seek shade whenever possible.
  • There is no such thing as a safe tan.  This includes those gotten in tanning salons.

Related posts:

Sun Protection (March 19, 2009)

Melanoma Review (February 25, 2008)

Skin Cancer—Melanoma (December 8, 2008)

Melanoma Skin Screening Is Important (April 29, 2009)

Skin Cancer -- Basal Cell Carcinoma  (December 3, 2008)

Skin Cancer – Squamous Cell Carcinoma  (December 4, 2008)

Moles Should Not Be Treated by Lasers  (July 27, 2009)

Tanning Beds = High Cancer Risk (August 3, 2009)

 

 

REFERENCES

Skin Cancer: More than Skin Deep; Advances in Skin & Wound Care. 22(12):574-580, December 2009.; doi: 10.1097/01.ASW.0000363470.25740.a2; Gordon, Randy M.

2 comments:

Anonymous said...

So what to do for those of us who grew up in the 60s when summer sunburn was pretty standard in sunny area?

rlbates said...

Have a good skin exam by your dermatologist to catch any skin cancers early.