Firefighters and Colorectal Cancer

By Christine L. Sardo Molmenti, Anne L. Golden, Penny Stern and Jacqueline M. Moline

It is not very common to sit down with fellow firefighters or friends and say, “Hey, does anyone want to talk about how we can prevent colorectal cancer?” While it may not sound like a subject for “polite” conversation, it’s a good idea to give some thought to this important topic. Colorectal cancer is one of the most preventable cancers, yet it is the third most common cancer among men and women. Sadly, colorectal cancer is the second most deadly cancer for men and women combined, with only lung cancer-causing more cancer deaths in the US (1). It is estimated that 147,950 new cases of colorectal cancer will be diagnosed in 2020 and 53,200 individuals will unfortunately die from this disease (2). Colorectal cancer rates have declined over the past two decades among people 55 years and older, but rates are rising in those under-50 years of age (3).

Firefighters are at increased risk When it comes to colorectal cancer risk among firefighters, the majority of scientific studies shows an increase in the range of 10% to 45% more compared to the risk in the general population. To our knowledge, the only published research study that has focused on volunteer firefighters was conducted in Australia (4,5) and found that among male volunteer firefighters, the overall risk of colorectal cancer was not elevated, but the risk appeared to increase among those with a longer duration of service (20+ years). Among Australian women volunteer firefighters in this study, the risk of rectal cancer was 35% higher compared to the general population. The well-known National Institute for Occupational Safety and Health (NIOSH) study, (6) which included career firefighters from three urban areas of the U.S., found that both incidence (new cases) and death from colorectal cancer was higher compared to the general population. Furthermore, similar findings regarding increased risk for colorectal cancer were found when the results of 32 studies of colorectal cancer in firefighters were combined (7).

Risk factors for colorectal cancer

Risk factors fall into two groups: those we can change (modifiable) and those we cannot (non-modifiable). Modifiable risk factors include lifestyle factors such as being overweight or obese, regularly consuming red and processed meats, drinking alcohol, smoking, not engaging in regular physical activity, and spending long periods of time sitting. Non-modifiable risk factors include age (the median age of colorectal cancer diagnosis is 66 years of age), race (African Americans tend to be at higher risk), and a family history of colorectal cancer and/or colorectal polyps (2). Firefighters may be at higher risk for colorectal cancer due to their exposures. These include toxic chemicals produced during fires and, in particular, asbestos fibers which firefighters encounter at most structural fires since asbestos was the dominant thermal insulation and fire prevention material in use for decades.

Most cases of colorectal cancer are diagnosed at late stages which usually predicts worse outcomes and poorer survival. But it doesn’t have to be this way! When the cancer is caught early, more than 90% of patients will be alive five years after being diagnosed (2). This is especially important for firefighters since the most recently-published study of U.S. career firefighters (8) observed that male firefighters (in Florida) were significantly more likely to be diagnosed with late-stage colon cancer.

Screening for colorectal cancer

Screening is one of the most of effective ways of detecting colorectal cancer at its earliest stages and preventing cancer from developing in the first place by detecting pre-cancerous polyps. Blood in your stool (whether you can see it or not) can be caused by polyps or by a colorectal cancer, so it’s important for to find the source of bleeding to diagnose and treat the problem.

According to the U.S. Preventive Services Task Force (USPSTF) draft recommendation (as of October 27, 2020 and soon to be finalized) recommends screening beginning at age 45 (9) (and not waiting until age 50 for those at average risk for colorectal cancer). This can be done either by colonoscopy, which is the most frequently used method, or by looking at samples of stool for the presence of blood (known as the “fecal occult blood test,” which includes at-home tests like Cologuard). Both methods are effective; however direct examination (by colonoscopy) can not only detect pre-cancerous colorectal polyps but can remove them at the same time to prevent their progressing to cancer.

A polyp is a growth that forms on the lining of the colon or rectum. Most are not cancerous, but some have the potential of developing into cancer.

Know your family history of colorectal cancer and colorectal polyps

It’s very important to know if you have a family history of colorectal cancer and polyps, because if you do, the age to start screening may be earlier for you. For example, if you have a close relative (parent, sibling, child) who has been diagnosed with an advanced colorectal polyp, it is recommended that you start screening at either the age of 40 or 10 years prior to the age your relative was diagnosed. The recommendation is the same if you have a close relative who has been diagnosed with colorectal cancer (10-12).

In summary, colorectal cancer is a highly preventable, yet still deadly disease. The good news is there are two main ways that you can act right now to prevent this cancer. First, take a look at any potential risk factors you may have – Are you sedentary? Do you smoke or consume alcohol? What does your diet look like? You may lower your chance of developing polyps and colorectal cancer by adopting healthy habits such as not smoking, avoiding alcohol intake, striving to maintain a healthy body weight, being physically active, limiting red and processed meat (such as beef, cold cuts, bacon, and hot dogs) and eating a diet with a lot of fresh fruits, vegetables, and other sources of fiber. Second, if you are 45 or older, it’s time to get screened, so don’t delay in making an appointment. Call your primary care provider to help you do this. If you are 40 or older, it may also be time for you to get screened. Take an inventory among your close relatives, parents, siblings, children to find out if any of them have been diagnosed with an advanced colorectal polyp. If so, you should be screened now or 10 years prior to the age they were diagnosed with a polyp, whichever is sooner. The National Colorectal Cancer Roundtable and American Cancer Society have developed resources in a “GI Brief ” to help you learn more about screening.

The American Institute for Colorectal Cancer (AICR) provides a summary of all the colorectal studies related to nutrition, diet, obesity, and physical activity as well as a number of resources

https://www.aicr.org/research/the-continuous-update-project/colorectal-cancer/

References

1. American Cancer Society. Colorectal Cancer Facts and Figures 2011-2013.

2. Society AC. Colorectal Cancer Facts and Figures 2020-2022. 2020.

3. Abualkhair WH, Zhou M, Ahnen D, Yu Q, Wu XC, Karlitz JJ. Trends in Incidence of Early-Onset Colorectal Cancer in the United States Among Those Approaching Screening Age. JAMA Netw Open. 2020.

4. Glass DC, Pircher S, Del Monaco A, Hoorn SV, Sim MR. Mortality and cancer incidence in a cohort of male paid Australian firefighters. Occup Environ Med. 2016;73(11):761-771.

5. Glass DC, Del Monaco A, Pircher S, Vander Hoorn S, Sim MR. Mortality and cancer incidence among female Australian firefighters. Occup Environ Med. 2019;76(4):215-221.

6. Daniels RD, Kubale TL, Yiin JH, et al. Mortality and cancer incidence in a pooled cohort of US firefighters from San Francisco, Chicago and Philadelphia (1950-2009). Occup Environ Med. 2014;71(6):388-397.

7. LeMasters GK, Genaidy AM, Succop P, et al. Cancer risk among firefighters: a review and meta-analysis of 32 studies. J Occup Environ Med. 2006;48(11):1189-1202.

8. Lee DJ, Koru-Sengul T, Hernandez MN, et al. Cancer risk among career male and female Florida firefighters: Evidence from the Florida Firefighter Cancer Registry (1981-2014). Am J Ind Med. 2020;63(4):285-299.

9. United States Preventive Services Task Force (USPSTF). https://www.uspreventiveservicestaskforce.org/uspstf/draft-recommendation/colorectal-cancerscreening3 October 27, 2020.

10. Gupta S, Lieberman D, Anderson JC, et al. Recommendations for Follow-Up After Colonoscopy and Polypectomy: A Consensus Update by the US Multi-Society Task Force on Colorectal Cancer. Am J Gastroenterol. 2020;115(3):415-434.

11. Molmenti CL, Kolb JM, Karlitz JJ. Advanced Colorectal Polyps on Colonoscopy: A Trigger for Earlier Screening of Family Members. Am J Gastroenterol. 2020;115(3):311-314.

12. Kolb JM MC, Patel SG, Lieberman DA, Ahnen DJ. Increased risk of colorectal cancer tied to advanced colorectal polyps; an untapped opportunity to screen first-degree relatives and decrease cancer burden. Am J Gastroenterol. 2020.