Follow-up LDCT screening for lung cancer decreases recall rates.
The early recall rate for suspicious findings from lung cancer screening significantly decreased with the second and subsequent low-dose multislice CT (MSCT) screening, according to a study published in the Journal of Thoracic Oncology.
Researchers from Germany sought to determine recall rates associated with follow-up (two to four) LDCT screenings for lung cancer. They analyzed the basic characteristics for the annual rounds and the first three years with complete follow-up since time of randomization.
Data were obtained from the German Lung Cancer Screening Intervention Trial (LUSI) after the fourth screening round and three-year follow-up was completed. The researchers looked at early recall rate, detection rate, interval cancers, and the proportion of advanced cancers. A total of 2,035 subjects who received no intervention were compared with 2,029 subjects, aged 50 to 69, with a history of heavy tobacco smoking, who underwent five annual screens.
In reporting the results, the authors wrote, “Early recall rates were significantly lower in the subsequent screening rounds than in the first one if the MSCT information from the previous screening rounds was available. Detection and biopsy rates were around 1 percent or lower, ratio of malignant:benign biopsies 1:1.6-1:3.”
There was a decline in the early recall rate from 20% in the first screening round to 3% to 4% in rounds 2 to 4. Lung cancer detection was 1.1% in the first round, and dropped to an average of 0.5% for the subsequent rounds.
After an almost identical cumulative number of advanced lung cancers and overall mortality among both groups in the first two years, the number of advanced cancers in the screening group began to decline in the third year.
“Our recent data may settle one concern regarding high recall rates in routine MSCT screening, but also indicate that screening must be strictly organized in order to be effective,” the authors concluded. “Performance indicators are similar to those in mammography screening. Nevertheless, possible consequences for the participants (diagnostic workup of suspicious findings, biopsies) are more invasive than in mammography screening.”