Wednesday, March 24, 2010

Skin Cancer

The entire March issue of Archives of Dermatology appears to be dedicated to skin cancer – non-melanoma and melanoma. 

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 carcinoma (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).

 

Prevention Tips:

  • Children should be taught the correct use of sunscreen.   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.

  • 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.

  • Everyone needs to wear a hat and sunglasses with 99% to 100% UVA absorption.

  • Exposure should be avoided between the hours of 10 AM and 4 PM when the sun is the strongest.  Sun-protective clothing and shade are helpful in avoiding exposure.

  • There is no such thing as a safe tan.  This includes those gotten in tanning salons.

 

Recent News Stories

Non-Melanoma Skin Cancer Cases Jump:  Dr. Jennifer Ashton Discusses Most Common Cancer, Risk Factors, When to Go to the Doctor

Skin Cancer Epidemic?  -- Dr Sanjaya Gupta, CNN

 

Melanoma Related News:

A mother's inspirational skin cancer battle By Jane Elliott, Health reporter, BBC News

Katie’s Fight  -- the blog of the woman featured in the BBC story

 

 

Related blog 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

Incidence Estimate of Nonmelanoma Skin Cancer in the United States, 2006; Arch Dermatol. 2010;146(3):283-287; Howard W. Rogers; Martin A. Weinstock; Ashlynne R. Harris; Michael R. Hinckley; Steven R. Feldman; Alan B. Fleischer; Brett M. Coldiron

Increased Risk of Second Primary Cancers After a Diagnosis of Melanoma; Arch Dermatol. 2010;146(3):265-272.; Porcia T. Bradford; D. Michal Freedman; Alisa M. Goldstein; Margaret A. Tucker

Economic Burden of Melanoma in the Elderly Population: Population-Based Analysis of the Surveillance, Epidemiology, and End Results (SEER)–Medicare Data; Arch Dermatol. 2010;146(3):249-256; Anne M. Seidler; Michelle L. Pennie; Emir Veledar; Steven D. Culler; Suephy C. Chen

3 comments:

StorytellERdoc said...

Darn you, Ramona! Posting this after we just got back from Hilton Head! LOL Seriously, good advice and reminder to always "cover-up" with lotion or spray. The new aerosol sprays, SPF 30+, are a God-send to all parents.

Hope your day is going well.
J

Suze said...

I am so glad you are raising this. I live in Australia and am a sun avoider but it takes its toll. A few months ago I had a birthmark removed and to my horror it was melanoma. It was a freak find after a year of health scares.

Unfotunately I know many who have this and they are not always visible and it is so sad to see a young person leave a family behind.

DBenzil said...

Great summary-useful to all. I will redouble my efforts with my sun crazy 20 year old daughter-they think they are invicible