Diagnosing early-stage lung cancer with low-dose CT screening drastically improves the long-term survival rate of cancer patients, a major international study has shown.
Lung cancer survival rates were 80% at 20 years among 1285 participants in the International Early Lung Cancer Action Program (I-ELCAP) trial who had cancers detected by low dose CT, according to findings presented at the annual meeting of the Radiological Society of North America (RSNA 2022).
Study investigator Dr Claudia Henschke, director of the Early Lung and Cardiac Action Program at the Icahn School of Medicine at Mount Sinai, New York, said the latest results from the program that started in 1992 reflected the high cure rate of screen-detected lung cancers.
“What we present here is the 20-year follow-up on participants in our screening program that were diagnosed with lung cancer and subsequently treated,” she said.
“The key finding is that even after this long a time interval they are not dying of their lung cancer.”
The I-ELCAP study grew out of the landmark National Lung Screening Trial, with follow up expanded to a multi-institutional, international cohort of 87,416 participants, 40 years of age and older, current, former, and never smokers who had undergone low dose CT screening.
In 2006, the researchers identified a 10-year survival rate of 80% for the 484 patients whose cancer was identified by CT screening.
The latest analysis included data for 1,285 I-ELCAP participants who were diagnosed with early-stage lung cancer for whom the overall survival rate was 80% (95%CI:77-83%).
Dr Henschke told the meeting that the 20-year survival rate for 139 participants with nonsolid cancerous lung nodules and also 155 participants with nodules of part-solid consistency was 100%. For the 991 participants with solid nodules, the survival rate was 73% (95%CI: 69-77).
The researchers also estimated survival for clinical Stage IA lung cancers and for resected pathologic stage IA lung cancers measuring 10mm or less in average diameter of length and width on the same CT image.
Lung cancer survival for clinical Stage IA participants was 86% (95%CI:83-89), regardless of consistency. For participants with pathologic Stage IA cancers of 10 mm or less, the 20-year survival rate was 92% (95%CI: 87-96).
Dr Henschke said the findings demonstrated the importance of routine and early lung screening, noting that currently only 16% of lung cancers are diagnosed at an early stage, and more than half of people with lung cancer die within one year of being diagnosed.
“Ultimately, anyone interested in being screened needs to know that if they are unfortunate enough to develop lung cancer, that it can be cured if found early,” said Dr. Henschke.
In October 2022 the Medicare Services Advisory Committee (MSAC) recommended funding for a national lung cancer screening program with low dose CT in Australia that would be open to 50-70 year olds with a significant history of smoking.