背景 1999 年 1000 名早期肺癌行动计划 (ELCAP) 参与者的低剂量 CT (≤3 mGy) 筛查报告引发了国际 ELCAP (I-ELCAP) 合作，该合作招募了 31 567 名参与者参加年度低剂量 CT 筛查1992 年至 2005 年间。2006 年，I-ELCAP 研究人员报告称，通过年度筛查诊断出首次原发性肺癌的 484 名参与者的 10 年肺癌特异性生存率为 80%，其中临床 I 期肺癌的频率很高（ 85%）。目的 通过在扩大的 I-ELCAP 队列中每年进行低剂量 CT 筛查，确定首次原发性肺癌诊断参与者的 20 年肺癌特异性生存率，从而更新治愈率。材料和方法 对于 1992 年至 2022 年间参加符合 HIPAA 的前瞻性 I-ELCAP 队列并观察至 2022 年 12 月 30 日的参与者，使用 Kaplan-Meier 生存分析来确定 10 年和 20 年肺癌特异性生存参与者通过每年的低剂量 CT 筛查诊断出患有第一原发性肺癌。符合资格的参与者年龄至少 40 岁，当前或以前吸烟或从未吸烟但接触过二手烟草烟雾。结果 在 89 404 名 I-ELCAP 参与者中，1257 名 (1.4%) 被诊断患有第一原发性肺癌（684 名男性，573 名女性；中位年龄，66 岁；IQR，61-72），中位吸烟史为 43.0 包- 年（IQR，29.0-60.0）。中位随访时间为 105 个月（IQR，41-182）。治疗前 CT 出现临床 I 期的频率为 81%（1257 例中有 1017 例）。 1257 名参与者的 10 年肺癌特异性生存率为 81% (95% CI: 79, 84)，20 年肺癌特异性生存率为 81% (95% CI: 78, 83)， 181 名患有病理性 T1aN0M0 肺癌的参与者为 95%（95% CI：91, 98）。结论 2006 年报道的参加年度低剂量 CT 筛查并诊断出首次原发性肺癌的 I-ELCAP 参与者的 10 年肺癌特异性生存率为 80%，这一点一直持续存在，如更新的 20 年肺癌数据所示-扩展的 I-ELCAP 队列的特定生存率。 © RSNA，2023 另请参阅本期 Grenier 以及 Sequist 和 Olazagasti 的社论。

Background The low-dose CT (≤3 mGy) screening report of 1000 Early Lung Cancer Action Program (ELCAP) participants in 1999 led to the International ELCAP (I-ELCAP) collaboration, which enrolled 31 567 participants in annual low-dose CT screening between 1992 and 2005. In 2006, I-ELCAP investigators reported the 10-year lung cancer-specific survival of 80% for 484 participants diagnosed with a first primary lung cancer through annual screening, with a high frequency of clinical stage I lung cancer (85%). Purpose To update the cure rate by determining the 20-year lung cancer-specific survival of participants diagnosed with first primary lung cancer through annual low-dose CT screening in the expanded I-ELCAP cohort. Materials and Methods For participants enrolled in the HIPAA-compliant prospective I-ELCAP cohort between 1992 and 2022 and observed until December 30, 2022, Kaplan-Meier survival analysis was used to determine the 10- and 20-year lung cancer-specific survival of participants diagnosed with first primary lung cancer through annual low-dose CT screening. Eligible participants were aged at least 40 years and had current or former cigarette use or had never smoked but had been exposed to secondhand tobacco smoke. Results Among 89 404 I-ELCAP participants, 1257 (1.4%) were diagnosed with a first primary lung cancer (684 male, 573 female; median age, 66 years; IQR, 61-72), with a median smoking history of 43.0 pack-years (IQR, 29.0-60.0). Median follow-up duration was 105 months (IQR, 41-182). The frequency of clinical stage I at pretreatment CT was 81% (1017 of 1257). The 10-year lung cancer-specific survival of 1257 participants was 81% (95% CI: 79, 84) and the 20-year lung cancer-specific survival was 81% (95% CI: 78, 83), and it was 95% (95% CI: 91, 98) for 181 participants with pathologic T1aN0M0 lung cancer. Conclusion The 10-year lung cancer-specific survival of 80% reported in 2006 for I-ELCAP participants enrolled in annual low-dose CT screening and diagnosed with a first primary lung cancer has persisted, as shown by the updated 20-year lung cancer-specific survival for the expanded I-ELCAP cohort. © RSNA, 2023 See also the editorials by Grenier and by Sequist and Olazagasti in this issue.