Lung Cancer Screening CT for Firefighters

Early Cancer Detection in Firefighters With Low-Dose Chest CT: A Community-Based Approach

Firefighters are at increased risk for cancer due to exposure to carcinogenic substances. Current lung cancer screening guidelines are predominantly based on smoking history and do not take into account high risk occupational exposures such as firefighting. This study aims to provide chest computed tomography (CT) scans to firefighters to determine the prevalence of lung cancer, other cancers detectable on CT chest, and lung diseases associated with increased cancer risk.

Study Overview

• Status: Withdrawn
• Conditions: Lung Diseases; Lung Cancer; Lung Diseases, Interstitial; Interstitial Lung Disease; Occupational Exposure; Exposure to Pollution; Smoke Inhalation; Occupational Lung Disease; Exposure Occupational; Exposure, Inhalation
• Intervention / Treatment: Procedure: Low-dose Computerized tomography (CT) of Chest; Other: Questionnaires; Other: Medical History

Detailed Description

This is a single-group prospective interventional study and a community-based participatory project led by University of California, San Francisco and in close collaboration with the firefighter community in California.

PRIMARY OBJECTIVE:

I. Determine the prevalence of lung cancer, other cancers and cancer risk factors detectable on chest Computerized Tomography (CT) (Aim 1).

II. Identify imaging and non-imaging predictors of lung cancer and other cancers detectable on chest CT.

SECONDARY OBJECTIVE:

I. Determine the prevalence of incidental findings on chest CT (Aim 1).

II. Determine the risk factors for cancer development in firefighters (Aim 2).

EXPLORATORY OBJECTIVES:

I. Long term follow-up to determine the incidence of lung cancer and other cancers among firefighters.

II. Develop a firefighter cancer imaging registry.

OUTLINE:

Participants will be administered a single, low dose chest CT to included participants and collect comprehensive demographic, clinical, and occupational data. Participants will be followed up at 1-2 months, for at least 1 year and up to 10 years to collect any follow-up imaging and biopsy results, if applicable.

• Study Type: Interventional
• Phase: Not Applicable

Contacts and Locations

Study Locations

• United States
  • California
    • San Francisco, California, United States, 94143
      • University of California, San Francisco

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: Adult; Older Adult
• Accepts Healthy Volunteers: Yes

Description

Inclusion Criteria:

1. Age 35 years or greater. If the participant is above the age of 80, participants must be otherwise healthy and well-fit to undergo treatment if lung cancer were to be discovered.
2. Never smoker or quit more than 15 years ago.
3. Able to understand study procedures and to comply with them for the entire length of the study.
4. Ability of individual or legal guardian/representative to understand a written informed consent document, and the willingness to sign it.
5. Length in profession for 10 or more years. This includes both volunteer firefighting and professional firefighting, self-attested as verifiable by professional records.

Additional cases for Aim 2:

1. Age 18+, may include deceased firefighters.
2. A previous or current history of confirmed thoracic malignancy (except localized skin cancer, cancer in situ, or other localized cancers)

Exclusion Criteria:

• Aim 1:

  1. Contraindication to any study-related procedure or assessment.
  2. Personal history of malignancy within 5 years (except localized skin cancer, cancer in situ, or localized cancers that are definitively treated and are unlikely to recur) or lung cancer at any time.
  3. Participants will be assessed for active pregnancy per standard procedure for clinical lung cancer screening CT at University of California, San Francisco which includes asking the participants directly along with documentation of whether the negative pregnancy was self-reported or confirmed with a urine pregnancy test.
  4. Prior CT chest within 1 year.
  5. Symptoms highly suggestive of lung cancer, including unexplained weight loss of over 30 pounds (lbs) within the past 12 months or unexplained hemoptysis.
• Aim 2:

No exclusion criteria

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Prevention
• Allocation: Non-Randomized
• Interventional Model: Parallel Assignment
• Masking: None (Open Label)

Number of Arms

2

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Other: Firefighters (Lung Screening CT); Participants will receive a single, low-dose, chest CT without contrast as indicated for lung cancer screening. Participants will be followed up for at least 1 year following the scan and have ongoing medical record reviews.	Procedure: Low-dose Computerized tomography (CT) of Chest; Undergo CT for lung cancer screening; Other Names: Low-dose Chest CT; Chest CT Scan; Chest CT; Other: Questionnaires; Participants will complete questionnaires on or before the day of the scan.; Other: Medical History; Medical history will be obtained in person and via medical record review; Other Names: Medical Chart Review; Medical Record Review
Other: Firefighters with Previously Diagnosed Malignancy; Participants with a history of cancer will have a medical record review as part of a case-control cohort.	Other: Medical History; Medical history will be obtained in person and via medical record review; Other Names: Medical Chart Review; Medical Record Review

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Proportion of participants with detected lung cancers (Aim 1)	The proportion of participants with detected lung cancers will be determined by the frequency of image findings that indicate lung cancer, and an ultimate clinical diagnosis associated with the imaging finding.	Up to 10 years
Proportion of participants with detected other cancers (Aim 1)	The proportion of participants with detected cancers, other than lung, will be determined by the frequency of image findings that indicate other cancer, and an ultimate clinical diagnosis associated with the imaging finding.	Up to 10 years
Proportion of participants with occupational lung disease (Aim 1)	Occupational or work-related lung diseases are lung conditions that have been caused or made worse by long-term exposure to certain irritants in the workplace. The proportion of participants with occupational lung disease will be determined by the frequency of image findings that indicate occupationally associated lung disease, and an ultimate clinical diagnosis associated with the imaging finding.	Up to 10 years
Proportion of participants with diagnosed interstitial lung disease (Aim 1)	Interstitial Lung Disease (ILD) is a group of diseases that irritate, inflame, or scar the lungs and supporting air sacs. The proportion of participants with diagnosed interstitial lung disease will be determined by the frequency of image findings that indicate ILD, and an ultimate clinical diagnosis associated with the imaging finding.	Up to 10 years
Number of participants within of each Lung-RADS risk group	The Lung CT Screening Reporting and Data System (Lung-RADS) is a measure developed by the American College of Radiologists to standardize the reporting and management of screen-detected pulmonary nodules. Nodules are categorized as 0=Incomplete, 1=Negative, 2=Benign Appearance or Behavior, 3=Probably Benign, or 4A /4B /4X = Suspicious with an additional modifier of S=Other or C=Prior Lung Cancer to be added to the 4 category codes as needed. The frequency of participants within each Lung-RADS risk group as determined by imaging procedures will be reported.	Up to 10 years

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Percentage of participants with incidental clinical findings	The percentage of participants with incidental findings be determined by the frequency of image findings that indicate presence of possible coronary calcium, aortic aneurysm, thyroid nodules, liver pathology and osseous pathology and an ultimate clinical diagnosis associated with the imaging finding.	Up to 10 years
Number of risk factors identified as associated with cancer development	The number of not-yet identified risk factors that are determined to be significantly associated with the development of thoracic cancers will be determined using logistic regression methods.	Up to 10 years

Collaborators and Investigators

• Sponsor: University of California, San Francisco
• Collaborators: Hayward Firefighters Local 1909 of the International Association of Firefighters
• Investigators: Principal Investigator: Jae Ho Sohn, MD, MS, University of California, San Francisco

Study record dates

Study Major Dates

• Study Start (Estimated): March 31, 2026
• Primary Completion (Estimated): December 31, 2035
• Study Completion (Estimated): December 31, 2035

Study Registration Dates

• First Submitted: February 14, 2025
• First Submitted That Met QC Criteria: February 14, 2025
• First Posted (Actual): February 20, 2025

Study Record Updates

• Last Update Posted (Actual): April 13, 2026
• Last Update Submitted That Met QC Criteria: April 7, 2026
• Last Verified: March 1, 2026

More Information

Terms related to this study

• Keywords: Cancer Screening; Population research
• Additional Relevant MeSH Terms: Wounds and Injuries; Pathologic Processes; Neoplasms by Site; Neoplasms; Respiratory Tract Diseases; Respiration Disorders; Respiratory Tract Neoplasms; Thoracic Neoplasms; Burns; Burns, Inhalation; Pathological Conditions, Signs and Symptoms; Lung Diseases; Lung Neoplasms; Respiratory Aspiration; Lung Diseases, Interstitial; Smoke Inhalation Injury; Health Care Quality, Access, and Evaluation; Investigative Techniques; Epidemiologic Methods; Data Collection; Health Care Evaluation Mechanisms; Quality of Health Care; Public Health; Environment and Public Health; Records; Medical Records; Surveys and Questionnaires; Health Records, Personal
• Other Study ID Numbers: 24053; NCI-2025-00336 (Registry Identifier: NCI Clinical Trials Reporting Program (CTRP))

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: NO

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: No