Challenges and Opportunities for Occupational Epidemiology in the Twenty-first Century

Research Recommendations for Selected IARC-Classified Agents: Impact and Lessons Learned

BACKGROUND

The International Agency for Research on Cancer (IARC) Monographs program assembles expert working groups who publish a critical review and evaluation of data on agents of interest. These comprehensive reviews provide a unique opportunity to identify research needs to address classification uncertainties. A multidisciplinary expert review and workshop held in 2009 identified research gaps and needs for 20 priority occupational chemicals, metals, dusts, and physical agents, with the goal of stimulating advances in epidemiological studies of cancer and carcinogen mechanisms. Overarching issues were also described.

OBJECTIVES

In this commentary we review the current status of the evidence for the 20 priority agents identified in 2009. We examine whether identified Research Recommendations for each agent were addressed and their potential impact on resolving classification uncertainties.

METHODS

We reviewed the IARC classifications of each of the 20 priority agents and identified major new epidemiological and human mechanistic studies published since the last evaluation. Information sources were either the published Monograph for agents that have been reevaluated or, for agents not yet reevaluated, Advisory Group reports and literature searches. Findings are described in view of recent methodological developments in Monographs evidence evaluation processes.

DISCUSSION

The majority of the 20 priority agents were reevaluated by IARC since 2009. The overall carcinogen classifications of 9 agents advanced, and new cancer sites with either "sufficient" or "limited" evidence of carcinogenicity were also identified for 9 agents. Examination of published findings revealed whether evidence gaps and Research Recommendations have been addressed and highlighted remaining uncertainties. During the past decade, new research addressed a range of the 2009 recommendations and supported updated classifications for priority agents. This supports future efforts to systematically apply findings of Monograph reviews to identify research gaps and priorities relevant to evaluation criteria established in the updated IARC Monograph Preamble. https://doi.org/10.1289/EHP12547.

Epidemiological Research on Occupational and Environmental Carcinogens

The cancer risk associated with exposure to environmental and occupational carcinogens such as asbestos, benzene, radiation, or lifestyle carcinogens such as cigarette smoking depends on the entire history of exposure to the carcinogen, including the age of exposure and the time-varying intensity of exposure [...].

Challenges to and facilitators of occupational epidemiology research in the UK

This study investigated the challenges and facilitators of occupational epidemiology (OE) research in the UK, and evaluated the impact of these challenges. Semi-structured in-depth interviews with leading UK-based OE researchers, and a survey of UK-based OE researchers were conducted. Seven leading researchers were interviewed, and there were 54 survey respondents. Key reported challenges for OE were diminishing resources during recent decades, influenced by social, economic and political drivers, and changing fashions in research policy. Consequently, the community is getting smaller and less influential. These challenges may have negatively affected OE research, causing it to fail to keep pace with recent methodological development and impacting its output of high-quality research. Better communication with, and support from other researchers and relevant policy and funding stakeholders was identified as the main facilitators to OE research. Many diseases were initially discovered in workplaces, as these make exceptionally good study populations to accurately assess exposures. Due to the decline of manufacturing industry, there is a perception that occupational diseases are now a thing of the past. Nevertheless, new occupational exposures remain under-evaluated and the UK has become reliant on overseas epidemiology. This has been exacerbated by the decline in the academic occupational medicine base. Maintaining UK-based OE research is hence necessary for the future development of occupational health services and policies for the UK workforce.

Descriptive Epidemiology of Cancers in Togo from 2009 to 2016

Background: Cancer is a global public health problem. According to World Report on Cancer in 2000, developing countries are becoming increasingly affected. Methods: This retrospective and descriptive 8-year study of all histological confirmed cancers was conducted using data from the anatomical pathology laboratory registry of Togo’s only laboratory. The parameters were frequency, site and histological type as well as age and gender. Results: We found 1,738 cancers in patients aged from 4 months to 109 years (mean, 50.4 ± 4. The sex ratio (M/F) was 1.3. The most frequent localizations of the cancers were the prostate (10.3%) followed by the breast (9.9%), the stomach (8.4%) and the cervix (7.2%). In women, the median age was 47.4 ± 2.9 years, and the most common cancers were breast cancer (21.2%), followed by cervical cancer (16.3%). In men, the median age was 53.2 ± 7.3 years and the most frequent cancers were prostate cancer (18.5%), non-Hodgkin’s lymphoma (13.2%) and stomach cancer (10.7%). In children, Burkitt’s lymphoma (41.8%), retinoblastoma (11.6%) and nephroblastoma (9.6%) were the most important cancers. Conclusion: Cancers are frequent in Togo, those of the prostate, breast and cervix being most important with a worse prognosis. Emphasis should be placed on early detection and diagnosis.