Introduction Diffuse lung cysts occur owing to several diseases; however, diffuse cystic lung metastases are very rare in the case of lung cancer. We report a rare case of diffuse cystic lung metastases from lung adenocarcinoma and reviewed previously reported cases of cystic lung metastases for lung cancer and determined their characteristics. Case Presentation A 78-year-old Japanese woman with advanced lung adenocarcinoma was positive for the epidermal growth factor receptor gene mutation exon 21 L858R and had been treated with osimertinib. She presented with multiple bilaterally positioned thin-walled lung cysts and pneumothorax. Lung cysts were diagnosed as cystic lung metastases from lung cancer, and carboplatin, pemetrexed, and pembrolizumab were subsequently administered. All cysts markedly decreased in size, and some disappeared. Conclusion Effective treatment methods for cystic lung metastases from lung cancer have not been reported. To our knowledge, this is the first case of cystic lung metastases that were successfully treated with chemotherapy.

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奥希替尼靶向治疗非小细胞肺癌患者弥漫性囊性肺转移瘤的成功化疗：文献综述和罕见病例报告。

简介 弥漫性肺囊肿由多种疾病引起；然而，弥漫性囊性肺转移在肺癌中非常罕见。我们报告了一例罕见的肺腺癌弥漫性囊性肺转移病例，并回顾了之前报道的肺癌囊性肺转移病例并确定了其特征。病例介绍 一名 78 岁日本女性患有晚期肺腺癌，表皮生长因子受体基因突变外显子 21 L858R 呈阳性，曾接受奥希替尼治疗。她出现多发性双侧薄壁肺囊肿和气胸。肺囊肿被诊断为肺癌囊性肺转移，随后给予卡铂、培美曲塞和派姆单抗。所有囊肿的大小均明显减小，有些囊肿消失。结论 肺癌囊性肺转移的有效治疗方法尚未见报道。据我们所知，这是首例通过化疗成功治愈的囊性肺转移瘤病例。