Other Asbestos Cancers
There is some evidence to suggest that exposure to asbestos also elevates the risk of developing cancer in other organs of the body. However, this has not been well researched and consequently, a consistent relationship between asbestos exposure and other types of cancers has not been definitively proven.
Elevated Risk for Colorectal Cancer Remains Controversial
Studies of asbestos workers suggest that cancer of the colon and rectum may be linked with asbestos exposure. However, there are also studies that have evidence to the contrary.
In 1964, a study titled “Asbestos Exposure and Neoplasia”, published in the Journal of the American Medical Association found that among 632 insulation workers, who entered the trade before 1943 and were followed through 1962, there were 29 deaths from cancer of the colon, rectum and stomach. The expected number of deaths from these cancers was a little over nine.
A study published in 1994 titled “Asbestos, Cement, and Cancer in the Right Part of the Colon” published in Occupational & Environmental Medicine studied the problem of elevated colon cancer risk from asbestos exposure across industry lines.
The researchers evaluated 2,507 asbestos cement or cement workers, 3,965 workers from an assortment of other trades and 8,092 fishermen. All of the study participants were employed for a minimum of one year in their respective trades. The observation period began 15 years after employment to allow for the latency period associated with asbestos-induced cancer.
What they observed was that asbestos cement and cement workers had a slightly elevated risk of colorectal cancer as a result of an increase in the number of incidence of cancer only in the right part of the colon. The ratio of right colon cancer among the asbestos cement and cement workers was 4.8 as compared with 0.4 among the participants employed in other trades and 1.5 among the fishermen.
Length of Asbestos Exposure may Affect the Risk for Colon and Gastrointestinal Cancers
The Agency for Toxic Substance and Disease Registry (ATSDR), which is a part of the Centers for Disease Control and Prevention (CDC), states the following about asbestos exposure and colon/gastrointestinal cancers:
- “Some evidence shows that short-term (acute) oral exposure to asbestos might bring on precursor lesions of colon cancer, and that long-term (chronic) oral exposure might increase the incidence of gastrointestinal tumors.
- Some of these increases were statistically significant. However, the magnitudes of increases in cancer incidence tended to be rather small and might be related to other risk factors such as smoking. Also, these studies were conducted on worker populations, with generally higher exposures; still, only small and inconsistent elevations have been reported.”
Only a few Studies Report on Asbestos Exposure and Kidney, Brain, Bladder, and Laryngeal Cancers
The causal relationship between asbestos exposure and other forms of cancer has not been completely proven because there are only a handful of studies that have assessed this association.
ATSDR noted the following:
- “Some studies have noted excess deaths from, or reported cases, of certain cancers such as the kidneys (two studies), brain (one study), and bladder (one study). Several epidemiologic studies have reported an increased risk of laryngeal cancer in workers exposed to asbestos.
- In contrast, other epidemiologic studies have not found a strong link between increased risk of cancers and asbestos exposure (except for cancers of the lungs and surrounding areas).”