Department of Thoracic Surgery, European Institute of Oncology, Milan, Italy.
Departments of Epidemiology and Biostatistics, European Institute of Oncology, Milan, Italy.
J Thorac Oncol. 2014 Jul;9(7):935-939. doi: 10.1097/JTO.0000000000000200.
Low-dose computed tomography (LD-CT) screening can reduce lung cancer mortality; however, it is essential to improve nodule management protocols. We analyze the performance of the diagnostic protocol of the Continuous Observation of SMOking Subjects single-center screening study, after long-term follow-up.
Between 2004 and 2005, 5203 asymptomatic high-risk individuals (≥20 pack-years, aged 50 years or older) were enrolled to undergo annual LD-CT for 5 years. Nodules 5 mm or smaller underwent repeat LD-CT a year later. Nodules larger than 5.0 mm and 8.0 mm or smaller received LD-CT 3 to 6 months later. Nodules larger than 8.0 mm or growing underwent CT-positron emission tomography. True positives were any stage prevalent lung cancer, progressing nodules diagnosed at stage 1, localized multifocal cancer, or new nodules diagnosed at any stage. False negatives were progressing nodules diagnosed at stage >1. False positives were benign nodules resected surgically.
Compliance was 79% over 5 years; 175 primary lung cancers were detected (0.76% per year), 136 (77.7%) were N0M0 and three were interval cancers. Eleven second primary lung cancers were diagnosed. Resectability was 87.4%; postoperative mortality 0.6%. Recall was 6.4% overall, 10.1% at baseline. False negatives were 14 of 175 (8%). Protocol sensitivity was 158 of 175 (90%); specificity 4994 of 5028 (99.4%); positive predictive value was 158 of 187 (84.5%); and negative predictive value was 4994 of 5016 (99.7%). Twenty-nine of 204 (14.2%) benign lesions were diagnosed surgically. Five-year overall and cancer-specific survival were 78% (95% confidence interval, 72-84) and 82% (95% confidence interval, 76%-88%) respectively.
The performance of the CT protocol was satisfactory with an acceptable number of benign lesions biopsied surgically, low recall rate, and good oncological outcomes. However, interval and advanced cancers, and misdiagnoses, need to be reduced, perhaps by risk modeling and use of serum markers.
低剂量计算机断层扫描（LD-CT）筛查可以降低肺癌死亡率；然而，改进结节管理方案至关重要。我们分析了经过长期随访后，连续观察吸烟人群（SMOking Subjects）单中心筛查研究诊断方案的表现。
2004 年至 2005 年间，共有 5203 名无症状高危个体（≥20 包年，年龄≥50 岁）入组，进行为期 5 年的年度 LD-CT 检查。直径 5 毫米或以下的结节在 1 年后进行重复 LD-CT 检查。直径大于 5.0 毫米且小于或等于 8.0 毫米的结节在 3 至 6 个月后进行 LD-CT 检查。直径大于 8.0 毫米或生长的结节进行 CT-正电子发射断层扫描。真阳性是任何阶段的肺癌，进展期结节诊断为 1 期，局部多灶性癌症或任何阶段新诊断的结节。假阴性是进展期结节诊断为 1 期以上。假阳性是经手术切除的良性结节。
5 年内的依从率为 79%；共检出 175 例原发性肺癌（每年 0.76%），136 例（77.7%）为 N0M0，3 例为间隔期癌症。诊断出 11 例第二原发性肺癌。可切除率为 87.4%；术后死亡率为 0.6%。总的召回率为 6.4%，基线时为 10.1%。假阴性为 175 例中的 14 例（8%）。方案敏感性为 175 例中的 158 例（90%）；特异性为 5028 例中的 4994 例（99.4%）；阳性预测值为 187 例中的 158 例（84.5%）；阴性预测值为 5016 例中的 4994 例（99.7%）。204 例（14.2%）良性病变经手术诊断。5 年总生存率和癌症特异性生存率分别为 78%（95%置信区间，72-84）和 82%（95%置信区间，76%-88%）。
该 CT 方案的表现令人满意，接受手术活检的良性病变数量可接受，召回率低，且肿瘤学结果良好。然而，需要减少间隔期和晚期癌症以及误诊，这可能需要通过风险建模和使用血清标志物来实现。
