目的:了解15mm以下和16～30mm两组周围型肺癌的临床表现以及影像学表现的差别。方法:回顾性分析经手术和病理证实的15mm以下周围型小肺癌59例和16～30mm周围型肺癌85例的临床表现以及胸部平片和CT表现。结果:1)15mm以下周围型小肺癌59例中,病理Ⅰ期53例,Ⅱ期以上6例。16～30mm周围型肺癌85例中,病理Ⅰ期19例,Ⅱ期以上66例。2)胸部平片对15mm以下周围型小肺癌的检出率为52.5%,漏诊率为47.5%;对16～30mm周围型肺癌的漏诊率为2.4%。16～30mm周围型肺癌的毛刺、分叶和胸膜凹陷征等明显高于15mm以下组,而肿瘤密度中的含气型和中间型、支气管气相和支气管血管集束征的出现率,则以15mm以下组为多。结论:1)15mm以下周围型小肺癌的绝大多数无临床症状并且为病理Ⅰ期,其影像学表现和诊断具有重要的临床意义。2)15mm以下周围型小肺癌的影像学表现和检出率与16～30mm周围型肺癌比较有明显差别。 Objective: To understand the clinical manifestations and imaging findings of peripheral lung cancer of 15mm below and 16 ~ 30mm. Methods: The clinical manifestations, chest radiographs and CT findings of 59 cases of peripheral small lung cancer and 15 cases of 16 ~ 30mm peripheral lung cancer less than 15mm confirmed by operation and pathology were retrospectively analyzed. Results: 1) Among the 59 cases with small peripheral lung cancer less than 15mm, 53 cases were stage Ⅰ, 6 cases were stage Ⅱ. Of the 85 patients with 16 ~ 30mm peripheral lung cancer, 19 cases were stage Ⅰ, 66 cases were stage Ⅱ. 2) The detection rate of chest radiograph was 52.5% and the rate of missed diagnosis was 47.5%. The rate of missed diagnosis of peripheral lung cancer of 16 ~ 30mm was 2.4%. 16 ~ 30mm peripheral lung cancer burr, lobulation and pleural indentation was significantly higher than 15mm below the group, and the tumor density in the gas-type and intermediate, bronchial gas and bronchial bundles signs of the incidence, then the following 15mm More groups. Conclusions: 1) The majority of small peripheral lung cancer less than 15mm have no clinical symptoms and are stage Ⅰ, and their imaging findings and diagnosis have important clinical significance. 2) Imaging findings and detection rate of peripheral small lung cancer less than 15mm were significantly different from those of peripheral lung cancer of 16 ~ 30mm.