The mortality for lung cancer is reduced in a Low Dose CT Scan Screening program compared with conventional public health surveillance for former workers exposed to asbestos

Fabio BARBONE, University of Udine, Italy
BARBONE F. 1,2,3 , BARBIERO F. 1,4 , ROSOLEN V. 1 , GIANGRECO M. 1 , PISA F. 1,2 , ZANIN T. 5 , MEDURI S. 6 , CASSETTI P. 7 , FOLLADOR A. 8 , BELVEDERE O. 8,9 , GROSSI F. 10 , FASOLA G. 8

1 Department of Medical and Biological Sciences, University of Udine, Udine, Italy
2 Institute of Hygiene and Clinical Epidemiology, University Hospital of Udine, Udine, Italy
3 Department of Medical Sciences, University of Trieste, Trieste, Italy
4 Health and Safety at Work Department (SPISAL), Local Health Authority No 12 Region of Veneto, Mestre, Italy
5 Health and Safety at Work Department. Local Health Authority No 2 (ASS2) Region of Friuli Venezia Giulia, Gorizia, Italy
6 Unit of Radiology, Hospital of Latisana - Palmanova, Latisana, Italy
7 Unit of Radiology, Hospital of Monfalcone, Gorizia, Italy
8 Department of Oncology, University Hospital of Udine, Udine, Italy
9 Department of Oncology, York Teaching Hospital, York, United Kingdom
10 Lung Cancer Unit, IRCCS AOU San Martino-IST National Cancer Research Institute, Genova, Italy

Purpose
To evaluate, in the area of the largest Italian shipyard, whether participation in a Low Dose CT Scan Screening (LDCT) (ATOM002 Study) is effective in reducing mortality for lung cancer in asbestos-exposed former workers, compared with conventional health surveillance program, often provided without a strict protocol and based on physician–expert's opinion.
Methods
Within a cohort of 2,433 occupationally asbestos-exposed men, enrolled in a public health surveillance program, we compared mortality and survival between participants in a screening program based on LDCT (n=926) and non-participants (n=1,507). For external comparison, we estimated the standardized mortality rate ratio (SMR) using Friuli Venezia Giulia regional standard rates (SMR_FVG) and Italian standard rates (SMR_ITA). For internal comparisons we performed Cox proportional hazard models to assess survival for all causes, all cancers, lung cancer and malignant neoplasm of the pleura. Final models were adjusted for smoking habits, age at start of follow-up, level of exposure to asbestos and Charlson-Quan comorbidity index.
Results
A reduction in mortality for lung cancer was found among subjects who participated in the ATOM002 study: SMR_FVG=0.55 IC95% 0.24-1.09, SMR_ITA=0.51 IC95% 0.22-1.01. In the group of other workers exposed to asbestos who did not participate in the ATOM002 study the SMR_FVG was respectively 2.07 (IC95% 1.53-2.73) and 1.98 (IC95% 1.47-2.61). Internal comparisons show a significant reduction in mortality for lung cancer in ATOM002 participants (HR=0.41 IC95% 0.17-0.96). Mortality was also reduced for all causes (HR=0.61 IC95% 0.44-0.84), but not for all cancers (HR=0.97 IC95% 0.62-1.50) and malignant neoplasm of the pleura (HR=0.86 IC95% 0.31-2.41).
 
Conclusions
In our cohort, health surveillance carried out with a strict 2-year protocol based on LDCT screening was more effective in reducing mortality for lung cancer than conventional public health surveillance.
 
Funding source
This study was carried out with no external funding.