[breadcrumb]
Asbestos has a strong link to cancers of the throat based on several epidemiological studies, although other studies achieved mixed results.
Cancers of the throat can include cancerous growth on several organs, including the entire throat (pharynx), the vocal cord area (larynx), or tonsils.[1] Of these, laryngeal (larynx) cancer has the strongest link to asbestos exposure.
The first major study to describe an increased risk of developing cancer of the larynx after exposure to asbestos was conducted back in 1960.[2] The study reviewed around 1,500 workers within occupations known to have high levels of asbestos exposure, especially employees of a particular asbestos company. A review of the data found that the number of deaths to laryngeal cancers was 28% higher than the expected value.
More recent and more comprehensive studies have confirmed these results. A review of 9 large cohort studies found that every one confirmed an association between asbestos exposure and the later development of laryngeal cancer.[3] Some studies also confirmed a dose-dependent relationship, meaning heavier exposures increased the likelihood of laryngeal cancers.
Studies like these have amassed a large body of evidence that asbestos can certainly cause cancers of the throat and especially the larynx. Results like these allowed the Institute of Medicine (IOM) to conclude in 2006, “that there is enough scientific evidence to state that exposure to asbestos causes cancer of the larynx.”[4] The risk increases further if the exposure victim also smoked tobacco or drinks alcohol heavily.
In accordance with these findings, many general information resources on asbestos exposure and cancer mention cancer of the throat as a possible outcome.[5][6]
The American Cancer Society notes that cancer of the hypopharynx, a part of the throat adjacent to the voice box (larynx), possibly has the strongest link to asbestos.[7]
However, despite the strength of all the available evidence, note that some studies dispute the fact that the link between throat cancer and asbestos is 100% proven and demonstrable. One study review notes that while a consistent and dose-dependent relationship can be observed, there is still a “discrepancy” within some of the data.[8] Another study review went even further to conclude that, “there was no evidence of a correlation between asbestos exposure and laryngeal cancer.”[9]
In light of these findings, know that while some experts and research institutions would be willing to say concretely that asbestos exposure does cause cancers of the throat, others may attempt to disagree by pointing to contradictory findings.
[1] https://www.mayoclinic.org/diseases-conditions/throat-cancer/symptoms-causes/syc-20366462
[2] https://www.jstor.org/stable/27726984?seq=1#page_scan_tab_contents
[3] https://www.ncbi.nlm.nih.gov/books/NBK20323/
[4] https://journals.lww.com/oncology-times/fulltext/2006/07250/IOM_Report__Asbestos_Can_Cause_Laryngeal_Cancer.12.aspx
[5] http://entcolumbia.org/staywell/document.php?id=33644
[6] https://ehs.oregonstate.edu/asb-when
[7] https://www.cancer.org/cancer/cancer-causes/asbestos.html
[8] http://scielo.isciii.es/pdf/mesetra/v61n239/en_10_revision2.pdf
[9] https://jamanetwork.com/journals/jamaotolaryngology/article-abstract/2589835
