Friday, May 30, 2014

Could this skin lesion be cancerous? Part 1


Identification of common types of skin cancer

Skin cancer is the most common form of cancer in the United States, occurring in over two million people each year.  Three of the most common types of skin cancer are squamous cell carcinoma, basal cell carcinoma, and melanoma. Each has characteristic features that can help alert you to the possibility that you may have developed a skin cancer.

Squamous cell skin cancers (SCC) arise from squamous cells which comprise most of skin’s outer layer (epidermis).  Since these are often related to UV exposure from the sun, they most commonly develop on the face, ears, arms or hands.  In their earliest form, they often appear as rough, scaly, red patches.  Unlike a skin rash that may fade with time, however, these rough patches persist and continue to progress slowly. Over time, they may become crusted, bleed, or develop an indentation in the center of the lesion. On occasion a SCC may have a wart-like appearance.

Approximately 40 to 60% of squamous cell skin cancers begin as a pre-malignant lesion known as an actinic keratosis (AK). Also known as solar
keratosis, these develop on sun-exposed areas of the body such as the face, arms, backs of hands, and lips. An AK is usually rough in texture, resembling a wart, and may be felt before actual changes of the skin are noted. Their color can range from flesh-toned to brown or red. Most are small, less than a half inch across. Approximately 10% of AKs progress to become squamous cell skin cancer.

Basal cell carcinoma (BCC) develops in the basal cell layer of the skin, the deepest layer of the epidermis. It is the most common type of skin cancer occurring in the U.S.  BCCs are usually seen in areas of the body that have been exposed to the sun, such as the face or arms. Warning signs that should alert someone to the possibility of a BCC include:
  • A persistent open sore that bleeds or oozes. On occasion, these may appear to heal only to re-open and bleed again.
  • A pearly bump or nodule that may be pink, red, or white. Small blood vessels may be apparent on the surface.
  • A lesion with a crater-like appearance with elevated border and indentation in the center.  
  •  An area of skin that is shiny and tight like a scar that develops without injury.
 
 Melanoma is a cancer of the pigment producing cells (melanocytes) of the skin. The great majority of melanomas can be attributed to exposure to ultraviolet (UV) radiation from the sun.  Melanoma begins on the surface of the skin but over time can extend deeper and in some cases, even spread throughout the body. Signs indicating that a skin lesion could be a melanoma include new pigmented area on the skin, or a change in size, shape or color of an existing mole. The ABCDE rule is another way to recognize melanomas:
  • Asymmetry: A mole that has an irregular shape, or the shape of one half does not match the other half.
  • Border: The edges are often irregular, blurred, rough, or notched in outline.
  • Color: Most moles are evenly colored, e.g. brown, black, or tan.  Changes in the shade or distribution of color throughout the mole can signal melanoma.
  • Diameter: Moles larger than ¼ inch (6 mm, the size of a pencil eraser) across are suspicious.
  • Evolving: The mole has changed over the past few weeks or months
Regular examination of the skin, by a physician or by self-examination, is the key to identifying skin cancers in their earliest stages.  Any suspicious lesion should be brought to the attention of your primary care doctor or a dermatologist. Next week we’ll look at how these common forms of skin cancer are treated and learn the best ways of preventing skin cancer.

Friday, May 23, 2014

A Primer on MERS

Middle East Respiratory Syndrome (MERS) is a respiratory illness occurring almost exclusively in countries in the Arabian Peninsula (Saudi Arabia, Yemen, Oman, the United Arab Emirates, Kuwait, Qatar, and Bahrain). According to the World Health Organization (WHO), almost 30% of those individuals who developed MERS have died from its complications.  Recent reports of MERS occurring in the U.S. have generated a great deal of concern regarding its potential for spread in this country.

What causes MERS?  MERS is a viral illness caused by a member of the coronovirus family (MERS-CoV).   Coronoviruses are responsible for causing other respiratory illnesses, including the common cold and Severe Acute Respiratory Syndrome (SARS).  MERS-CoV appears to have originated from an animal source. A close link between the MERS-CoV affecting both humans and camels has been noted.
 
Who is at risk for developing MERS?  Most cases of MERS have spread to others through close contact, such as family members or health care workers caring for an infected person. People with a weakened immune system, the elderly, and those with chronic diseases such as diabetes, cancer, and chronic lung disease appear to be at increased risk for developing MERS.
 
What are the symptoms of MERS?  Most MERS patients develop an acute respiratory illness with symptoms of fever, cough and shortness of breath. Severe cases can lead to the development of pneumonia and respiratory failure requiring breathing support with a ventilator.  Kidney failure and septic shock often contribute to fatal cases.  In a smaller percentage of cases, MERS causes a much less severe, cold-like illness, with uneventful recovery. 
 
How is the diagnosis confirmed?  When symptoms dictate, laboratory testing is used to confirm the diagnosis of MERS. Polymerase Chain Reaction testing (PCR) can be performed on a respiratory sample in active cases or blood testing for antibodies can be done to confirm a previous infection.
 
How is MERS treated?  There is no specific antiviral treatment currently available for MERS-CoV infection, nor is a vaccine available. Treatment of MERS hinges on treating its symptoms and providing supportive care in the event of organ failure.
 
How likely is an epidemic in this country?  MERS appears to be contagious only to a limited degree and the risk of a major outbreak in this country is extremely low.  As of this writing, only 3 cases of MERS have been confirmed in the U.S.  The first two cases both involved health care workers who were exposed to the MERS-CoV in Saudi Arabia and did not develop symptoms until they returned to the U.S. Both of these individuals were hospitalized and are doing well. The third case, the only known case acquired in the U.S., developed following a business meeting with one of the hospitalized patients prior to the time that they developed symptoms.  Interestingly, this third person was identified by blood testing only and did not show any symptoms of MERS.
 
What about traveling to the Middle East?  The Centers for Disease Control (CDC) has not advised against traveling to the Middle East because of MERS.  They have, however, advised people to protect themselves from respiratory illnesses when traveling by taking the following preventive actions:
  • Wash your hands often with soap and water for 20 seconds, and help young children do the same. If soap and water are not available, use an alcohol-based hand sanitizer.
  • Cover your nose and mouth with a tissue when you cough or sneeze, then throw the tissue in the trash.
  • Avoid touching your eyes, nose and mouth with unwashed hands.
  • Avoid personal contact, such as kissing, or sharing cups or eating utensils, with sick people.
  • Avoid undercooked meats and make sure that the water you drink is sterilized.

Friday, May 16, 2014

Lung Cancer Screening: when should it be considered?

Most people are aware of the many lives that have been saved through early detection and treatment of cancer.   A good example of this is regular Pap screening which has decreased cervix cancer mortality by at least 80%. Why then do we not hear much about screening for lung cancer, the leading cause of cancer deaths in the United States?  Shouldn’t a disease that results in more deaths than colon and breast cancer combined, both of which have effective screening tests, receive more attention?

To answer these questions, we first need to look at who gets lung cancer.  Over 80% of lung cancer occurs in association with one important risk factor---cigarette smoking.   Non-smokers or those without respiratory symptoms, such as cough or shortness of breath, are very unlikely to develop lung cancer.  A screening test applied to non-smokers would find lung cancer in a tiny percentage of those tested.  Furthermore, up until recently, it had never been proven that there was a screening test capable of saving lives, even when applied to smokers.

Earlier this year, the U.S. Preventive Services Task Force (USPSTF) published new recommendations for lung cancer screening that were largely based on the results of a study involving more than 53,000 current or former heavy smokers.  These were smokers who had at least a 30 pack-year history of smoking (one pack-year is defined as smoking a pack a day for one year) and were either currently smoking or had quit within the past 15 years.  These high-risk subjects received one of two screening tests, a standard chest x-ray or computed tomography of the chest (low-dose helical CT scan). At the end of the study, it was determined that by performing CT scans of the chest, lung cancer deaths could be reduced by 20%.

The USPSTF now advises “annual screening for lung cancer with low-dose computed tomography in adults ages 55 to 80 years who have a 30 pack-year smoking history and currently smoke or have quit within the past 15 years. Screening should be discontinued once a person has not smoked for 15 years or develops a health problem that substantially limits life expectancy or the ability or willingness to have curative lung surgery”

While the benefits of screening in high-risk individuals have been confirmed, screening is not without its own risks.  Sometimes a screening test can suggest that someone has lung cancer when cancer is not really present.  This can lead to costly and potentially dangerous tests, or even surgery, that wasn’t necessary. Additionally, the radiation received from repeated x-rays or CT scanning is capable of causing cancer on its own.

Even though lung cancer screening can reduce lung cancer deaths, it will never be as effective in reducing the development lung cancer as stopping smoking or not smoking in the first place.  The Centers for Disease Control (CDC) recommends the following measures to help lower your risk of developing lung cancer:

  • Don’t smoke. Smoking causes about 90% of lung cancer deaths in men and almost 80% of lung cancer deaths in women in the United States. The most important thing you can do to prevent lung cancer is to not start smoking, or to quit if you smoke.
  • Avoid secondhand smoke. Smoke from other people’s cigarettes, pipes, or cigars is called secondhand smoke. Make your home and car smoke-free.
  • Get your home tested for radon. The U.S. Environmental Protection Agency recommends that all homes be tested for radon.

Be careful at work. Health and safety guidelines in the workplace can help workers avoid carcinogens—things that can cause cancer.
 If you have any questions about lung cancer screening, please log into your account and send us your question. We are here to help.