Purpose: To evaluate prospectively the diagnostic performance of the New York Early Lung Cancer Action Project (NY-ELCAP) regimen in the diagnosis of early lung cancer at baseline and annual repeat computed tomographic (CT) screenings.
Materials and methods: Informed consent and institutional review board approval were obtained for this HIPAA-compliant study of baseline and annual repeat low-dose CT screening performed with a common regimen in asymptomatic individuals at 12 institutions in New York State. All 6295 participants were aged 60 years or older, had smoked for at least 10 pack-years, had no prior cancer, had not undergone chest CT in the previous 3 years, and were medically fit to undergo thoracic surgery. Median age was 66 years, and median smoking history was 40 pack-years. The proportion (and 95% exact confidence intervals [CIs]) of subjects with a positive result, as determined by using nodule size; the diagnoses of lung cancer resulting from subsequent work-up; and the distribution by cancer stage and cell type were determined. When relevant, 95% CIs for the proportions were calculated.
Results: Initial CT imaging led to recommendations for further work-up in 14.4% (95% CI: 13.5%, 15.3%) of the 6295 baseline screenings and 6.0% (95% CI: 5.1%, 6.6%) of the 6014 annual repeat screenings. Of 101 patients in whom the diagnosis of lung cancer resulted from baseline screening and three in whom a diagnosis of lung cancer was prompted by symptoms prior to the first scheduled repeat screening, 95 (91.3%) had no clinical evidence of metastases. Of the 20 patients in whom the diagnosis of lung cancer resulted from annual repeat screening, 17 (85%) showed no evidence of metastases. Of the 134 recommended biopsies, 125 (93.3%) resulted in diagnosis of lung cancer or another malignancy, while none of the 24 biopsies performed outside of the recommendation of the regimen resulted in diagnosis of lung cancer.
Conclusion: The NY-ELCAP regimen of screening revealed that annual CT screening for lung cancer resulted in identification of a high proportion of patients with early-stage disease.