Authors' objectives: To determine whether there is any evidence to support the (causal) association between being a firefighter and developing Hodgkin’s lymphoma.

Authors' results and conclusions: Overall, there were 32 studies retrieved in full and appraised further in this systematic review. Of these 32 studies that were appraised further, 15 studies were not relevant to the objective of this systematic review or did not provide relevant data to the objective; hence, these 15 studies will not be discussed further and the 17 primary studies are appraised and summarized. All of these primary studies gathered data by linking several administrative databases and extracting the relevant information to build their study population. Administrative databases were not built specifically to test the hypothesis/objective of these primary studies, hence the potential for biases associated with completeness of registration of individuals, accuracy and degree of completeness of the registered data as well the availability of variables essential in investigating the hypothesis are likely not present and cannot be taken into account when investigating the association of interest. Of these 17 primary studies employed in this systematic review, only two studies (one among female only) provided a positive association between being a firefighter and developing Hodgkin’s lymphoma while the remaining evidence showed negative or even a protective effect of developing Hodgkin’s lymphoma among firefighters. It should be noted though that the potential for selection, misclassification as well as surveillance bias may affect the observed outcome while important confounders, such as smoking status, Epstein-Barr virus infections and familial risk, cannot be excluded from potentially affecting the observed outcomes. As such, given the available evidence at present, at best, there is conflicting evidence in the association between being a firefighter and developing Hodgkin’s lymphoma. With regard to assessing causal association, as outlined by Sir Bradford Hill, the available evidence so far did not provide evidence to establish such a causal association.

Authors' methods: A comprehensive and systematic literature search was conducted on June 19, 2025. The search was done on commercial medical literature databases where a combination of key words was employed in this search. No limitation, such as on the language or date of publication, was implemented in any of these searches. A manual search was also planned and conducted on the references of the articles that were retrieved in full.

Project Status: Completed

URL for project: https://www.worksafebc.com/en/about-us/research-services/evidence-based-medicine-and-systematic-reviews

Year Published: 2025

URL for published report: https://www.worksafebc.com/en/resources/health-care-providers/guides/firefighting-and-hodgkins-lymphoma?lang=en&origin=s&returnurl=https%3A%2F%2Fwww.worksafebc.com%2Fen%2Fforms-resources%23sort%3DDate%26q%3DFirefighting%2520and%2520Hodgkins%2520Lymphoma%26f%3Alanguage-facet%3D%5BEnglish%5D%26tags%3DHealth%2520Care%2520Provider%7C13468b0b3f074f6bade3f57ac3cdfb8e%2CSystematic%2520Review%7Cf78c29d570c14ec3b5a394385905df70&highlight=Firefighting%20and%20Hodgkins%20Lymphoma

English language abstract: An English language summary is available

Publication Type: Mini HTA

Country: Canada

Organisation Name: WorkSafeBC

Contact Address: 6591 Westminster Highway, Richmond, BC, V7C 1C6 Canada. Tel: 604-231-8417; Fax: 604-279-7698

Contact Name: ebpg@worksafebc.com

Contact Email: ebpg@worksafebc.com

Copyright: WorkSafe BC