CT Screening Detects Curable Stage I Lung Cancer

NEW YORK--Spiral CT screeningof high-risk individuals could preventabout 80% of deaths from lung cancer,according to the latest results from thelarge collaborative I-ELCAP trial. "In ourstudy, the estimated 10-year lung-cancer-specific survival rate among the 484participants with disease diagnosed onCT, regardless of the stage at diagnosis ortype of treatment, was 80%," said ClaudiaI. Henschke, MD, of Weill Medical Collegeof Cornell University, leader of theInternational Early Lung Cancer ActionProgram (I-ELCAP). Dr. Henschke andher colleagues reported the results in arecent issue of the New England Journalof Medicine (355:1763-1771, 2006).

In the study, screening was definedaccording to the I-ELCAP protocol allowingdata from the participating institutionsto be pooled. Further, I-ELCAPprovided a management algorithm forbaseline CT and repeated CT screening.

Participants were at least 40 years ofage and were at risk for lung cancer dueto a history of cigarette smoking, occupationalexposure, or exposure to secondhandsmoke (with the exception ofpatients from Azumi, Japan, who participatedas part of their annual healthscreening program).

Between 1993 and 2005, a total of31,567 asymptomatic men and womenunderwent baseline CT screening. From1994 to 2005, a total of 27,456 annual CTscreenings were conducted. Biopsies asrecommended by the protocol were performedin 535 participants, and 492 werediagnosed with malignant disease (479lung cancers). Of these 479 lung cancers,405 were found at baseline and 74at an annual screening. Another 5 weredefined as interim diagnoses, promptedby the development of symptoms within12 months of the baseline screening.

Of the 484 participants diagnosed withlung cancer, 411 had surgery; 57 receivedradiation, chemotherapy, or both; and16 received no treatment. Two patientsdied within 4 weeks after surgery, for anoperative mortality rate of 0.5%.

Among the 412 participants (85%)with clinical stage I lung cancer foundby CT screening, the estimated 10-yearsurvival rate was 88%. This rose to 92%among the 302 patients with clinical stageI disease who had surgical resectionwithin 1 month of their diagnosis. All 8untreated patients with stage I diseasedied within 5 years of diagnosis.

Comparison to MammographyDr. Henschke compared the resultswith those of breast cancer screening."For lung cancer, the rates of detectionamong the participants in the study whowere 40 years of age and older were 1.3%on baseline CT screening and 0.3% onannual screening, values that wereslightly higher than those for the detectionof breast cancer on baseline screening(0.6% to 1%) and similar to thosefor annual screening (0.2% to 0.4%),among women 40 years of age and older,"she said.