One of the most devastating diseases in American communities today is lung cancer. Assume that you are an epidemiologist interested in determining whether or not there is a genetic predisposition to lung cancer. Discuss reasons why lung cancer might cluster in a family for non-genetic reasons.
PLEASE EXPLAIN WHETHER YOU AGREE WITH MY CLASSMATE RESPONSE TO THE ABOVE QUESTION AND WHY? (A MININUM OF 125 WORDS)
The US Centers for Disease Control and Prevention (CDC) and the National Cancer Institute say that a cancer cluster is a “greater-than-expected number of cancer cases that occurs within a group of people in a defined geographic area over a period of time.” (American Cancer Society, 2018).
In order to see if there is a greater number of cancers than expected, the number of cases seen is compared to what is typically seen in a similar group – such as a group with the same age, gender, and ethnicity. The cancers should either be all of the same type or types of cancer that are known to have the same cause. (American Cancer Society, 2016)
More than 1,000 suspected cancer clusters are reported to state health departments each year.
And a group of more than 100 different diseases, each type of cancer has its own risk factors and causes. (American Cancer Society, 2018).
When the cases of cancer do not seem to be random, there would be a closer check to find out if they are due to the same cause or carcinogen. Studying cancer clusters allows scientists to identify areas of increased cancer risk as well as figure out what is causing the increase in risk. For example, studying clusters of malignant mesothelioma led to the discovery of the link between asbestos exposure and this rare cancer. (American Cancer Society, 2018).
Lung cancer in non-smokers can be caused by exposure to radon, secondhand smoke, air pollution, or other factors. Workplace exposures to asbestos, diesel exhaust or certain other chemicals can also cause lung cancers in some people who don’t smoke.
A small portion of lung cancers occur in people with no known risk factors for the disease. Some of these might just be random events that don’t have an outside cause, but others might be due to factors that we don’t yet know about. (American Cancer Society, 2016)
Lung cancers in non-smokers are often different in some ways from those that occur in smokers. They tend to occur at younger ages. Lung cancers in non-smokers often have certain gene changes that are different from those in tumors from smokers. In some cases, these changes can be used to guide treatment. (American Cancer Society, 2016)
According to the US Environmental Protection Agency (EPA), Radon is the second leading cause of lung cancer in this country, and is the leading cause among non-smokers. (American Cancer Society, 2016).
Brothers, sisters, and children of people who have had lung cancer may have a slightly higher risk of lung cancer themselves, especially if the relative was diagnosed at a younger age. It’s not clear how much of this risk might be due to shared genes among family members and how much might be from shared household exposures (such as tobacco smoke or radon). (American Cancer Society, 2016).