A new Canadian study has found that men working in farming, the armed forces and the law are more likely to develop prostate cancer, while construction managers, supervisors and senior managers as well as those working in sports and recreation are less at risk.
Prostate cancer is the second-most commonly diagnosed cancer in men and the third leading cause of death from cancer. Advancing age is the greatest risk factor, with most cases diagnosed in men over the age of 65. Other known risks include having a family history of prostate cancer, ethnicity (prostate cancer is more common among men of African and Caribbean genetic backgrounds) as well as environmental factors such as having a diet low in fibre and high in fat.
So far, evidence has been mixed on the link between certain occupations and prostate cancer. Positive associations have been found for jobs that involve exposure to particular chemicals such as cadmium, arsenic, radiation, rubber manufacturing compounds and malathion insecticides. But wide-ranging population studies have been missing on the broad spectrum of common occupations.
Researchers used data from the National Enhanced Cancer Surveillance System (NECSS) population-based study conducted in eight Canadian provinces between the years 1994 and 1997. Looking at 1737 cases of prostate cancer from that time period, the researchers determined an elevated risk of prostate cancer for those in legal work, for farmers and farm/agriculture managers and for those in the armed forces. Elevated risk was also associated with men working for more than ten years in plumbing and office work.
The study found decreased risks of getting prostate cancer for those working in sports and recreation, construction managers and supervisors, travel clerks and those in government and senior management.
The study’s authors connected elevated risks associated with farming to more frequent exposure to pesticides, which can disrupt endocrine function and promote tumour growth. For men working in the armed forces, the researchers pointed to potential contributing factors such as exposure to metals, asbestos, fuels, radiation, whole body vibration, stress and shift work.
“Our study is one of the few large population-based studies that examined prostate cancer risk by job title and included non-occupational risk factors,” say the study’s authors, whose research is published in the journal Cancer Epidemiology. “Occupation and industry may act as weak surrogates for exposures but with very little knowledge on exposures linked to prostate cancer, this is an important step to identify job-specific exposures.”
One in eight men in Canada will be diagnosed with prostate cancer, according to Prostate Cancer Canada. In 2016, an estimated 4,000 men died from the disease and 21,600 received a prostate cancer diagnosis. Due to improved testing and better treatment options, however, the death rate from prostate cancer has dropped by 3.1 per cent between the years 2003 and 2012.
Prostate cancer can often be a slow-growing cancer, with some men living for many years without having it detected. Prostate Canada recommends regular testing for men over the age of 40 to increase the likelihood of cancer being detected at an early stage when more treatment options are available.