Colorectal Cancer: 35 Cases in Asbestos-Exposed Workers

Our plain-English summary of Colorectal Cancer: 35 Cases in Asbestos-Exposed Workers, by A. Porzio, A. Feola, G. Parisi, et al (Healthcare, 2023).

The study

• Authors: A. Porzio, A. Feola, G. Parisi, A. Lauro, C.P. Campobasso
• Journal: Healthcare
• Published: 2023;11(23)
• Cited by: 3 articles, as counted by NIH iCite
• Read it: PubMed · Publisher · Free full text

Abstract

Background: Asbestos is considered one of the major global work-related carcinogens. Some studies suggest a potential causal relationship between asbestos exposure and colorectal cancer (CRC). However, the role of asbestos in CRC carcinogenesis is still controversial.

Methods: 35 claims of occupational CRC among asbestos-exposed workers were reviewed. All claims were rejected by the Italian National Institute for Insurance against Accidents (INAIL) due to the "lack of scientific evidence in the causality" between asbestos exposure and CRC; causality was finally assessed in civil trials. All cases were categorized by age, gender, industry type, task, exposure and latency periods, anatomical location, and histopathological characteristics of CRC and concomitant respiratory diseases.

Results: Most workers were males aged 60 years or more and employed in occupational activities with extensive use of asbestos for over 20 years. In 31 out of 35 cases, CRC was diagnosed over 39 years after employment. Right-sided colic adenocarcinoma was diagnosed in nine cases; rectum was involved in eight cases. Respiratory comorbidities were observed in 22 workers.

Conclusions: Our study provides some interesting points in the assessment of the causal relationship between asbestos exposure and CRC.

In plain English

This was a case series from Campania, Italy. The authors reviewed 35 civil-court claims about workers with colorectal cancer. Nineteen were brought by living workers and 16 by relatives after the worker's death. INAIL, Italy's workers' insurance institute, had recognized all 35 as occupationally exposed to asbestos, but rejected the cancer claims for "lack of scientific evidence" of causality. Thirty-three of the 35 were men. Ages ranged from 57 to 90, with an average of 70.14 years. Twenty-two worked in the steel industry. The case table shows 33 exposed for 15 years or more. In 31 cases the cancer was diagnosed 39 or more years after exposure began. The cancer was in the right colon in nine workers, the left colon in three and the rectum in eight. In 14 the colon site was not specified, and one case was multifocal. Twenty-two workers had respiratory conditions, including five with asbestosis. Six had other risk factors, mostly smoking. The authors could not determine individual cumulative exposure. The authors concluded that their case series does not provide enough evidence of a causal relationship between asbestos exposure and colorectal cancer.

We wrote this plain-English summary from the full article with the help of AI, and a second AI model checked each sentence against the article. It is not the authors' wording; the abstract and the article are their own account.

What the study did and found

• Design: case series: review of claims submitted to the civil courts in Campania, Italy, seeking recognition of colorectal cancer as an occupational disease
• Who was studied: 35 workers with colorectal cancer (33 men, 2 women) in Campania, Italy, all hired between 1955 and 1976. INAIL had recognized their occupational asbestos exposure but rejected their occupational cancer claims for lack of scientific evidence of causality. Nineteen claims were submitted by the workers while alive; the 16 workers who died before submission had claims brought by relatives.
• Exposure: Occupational asbestos exposure; no fiber type is named. By industry: 22 of 35 in the steel industry (including steel manufacturing, synthetic fiber production and asbestos processing), 9 in metalworking, 3 in shipbuilding and 1 in the paper industry. Individual airborne fiber concentrations and cumulative doses were not available.
• Main results:
  • Nineteen claims were submitted directly by the workers while they were still alive. The other 16 workers had died before the claims were submitted, and their claims were brought by relatives.
  • Among the 35 workers, the average age was 70.14 years; the youngest was 57 and the oldest 90.
  • The article states that 33 of 35 workers were exposed for over 15 years and two for 8 to 10 years. Its case table shows one of the 33 (case 8) with exactly 15 years, so 33 had 15 years or more.
  • The latency period (from the start of exposure to diagnosis) ranged from 33 to 66 years.
  • The article states that in 31 of 35 cases colorectal cancer was diagnosed approximately over 39 years after exposure began. Its case table shows three of these at exactly 39 years, so 31 were at 39 years or more.
  • Cancer site among the 35: rectum in 8 (22.8%), right-sided colon in 9 (25.7%), left-sided colon in 3 (8.5%) and multifocal in 1.
  • In 14 of the 35 cases, the location of the colon cancer was unspecified.
  • Respiratory comorbidities were present in 22 of 35 workers (62.8%). These included 5 cases of asbestosis, 2 with pleural plaques, 3 with lung metastases from the colorectal cancer, and 2 nodules of undefined origin.
  • Colorectal cancer risk factors other than age were found in 6 cases: smoking in 4, alcohol use in 1, and familial adenomatous polyposis in 1. Data were not available for 8 workers.
  • Regional lymph nodes were involved in 17 of 35 cases (48.5%). High-grade cancer was diagnosed in 14 of 35 (40%).
  • In one illustrative case (case #4, a man with asbestosis), asbestos bodies were found in lung tissue. No asbestos fibers or ferruginous bodies were found in the colon sections.
• The authors' conclusion: The authors concluded that, given the study's limitations, their case series does not provide enough evidence of a causal relationship between asbestos exposure and colorectal cancer.
• Limitations the authors state:
  • Small sample of only 35 cases.
  • Individual cumulative asbestos exposure could not be determined.
  • Death certificates were available for only 16 of the 35 workers, those who died before the claims were submitted.
  • Information on the later clinical course of the cancer was missing for 19 cases.

Topics

Medical terms in this study, explained in our Lexicon: Colorectal Cancer, Asbestos Exposure, Carcinogenesis, Latency, Adenocarcinoma.

Related studies

• Colorectal Cancer and Asbestos Exposure: A Women's Health Perspective — A. Porzio, A. Feola, et al. (2024)
• Colorectal cancer in asbestos cement workers in Denmark — E. Raffn, E. Villadsen, et al. (1996)
• Pre-diagnostic serum levels of inflammation markers and risk of ovarian cancer in the prostate, lung, colorectal and ovarian cancer (PLCO) screening trial — B. Trabert, L. Pinto, et al. (2014)
• Drugs, doses, and durations of intraperitoneal chemotherapy: standardising HIPEC and EPIC for colorectal, appendiceal, gastric, ovarian peritoneal surface malignancies and peritoneal mesothelioma — L. Lemoine, P. Sugarbaker, et al. (2017)
• Occupational exposures and colorectal cancers: a quantitative overview of epidemiological evidence — E. Oddone, C. Modonesi, et al. (2014)
• Antioxidants in the chemoprevention of colorectal cancer and colorectal adenomas in the general population: a systematic review and meta-analysis — D. Papaioannou, K.L. Cooper, et al. (2011)

Browse return to medical research.