Departments of Medicine, Physiology and Biomedical Engineering, Mayo Clinic, Rochester, Minnesota, USA.
U.O. di Pneumologia e Terapia Semi-Intensiva Respiratoria "Servizio di Fisiopatologia Respiratoria ed Emodinamica Polmonare, Ospedale San Giuseppe" Multimedica IRCCS, Milano, Italy.
Thorax. 2017 Oct;72(10):937-945. doi: 10.1136/thoraxjnl-2017-210125. Epub 2017 Jul 8.
Pulmonary Langerhans cell histiocytosis (PLCH) is a diffuse lung disease that usually affects young adult smokers. PLCH affects different lung compartments; bronchiolar, interstitial and pulmonary vascular dysfunction may coexist to varying extents, resulting in diverse phenotypes. Analyses of PLCH tissues have identified activating mutations of specific mitogen-activated protein kinases (BRAF and others). The current consensus is that PLCH represents a myeloid neoplasm with inflammatory properties: the myeloid tumour cells exhibit surface CD1a expression and up to 50% of the cells harbour activating BRAF or other MAPK mutations. PLCH may be associated with multisystem disease. The detection of disease outside of the thorax is facilitated by whole body positron emission tomography. The natural history of PLCH is unpredictable. In some patients, disease may remit or stabilise following smoking cessation. Others develop progressive lung disease, often associated with evidence of airflow limitation and pulmonary vascular dysfunction. Due to the inability to accurately predict the natural history, it is important that all patients undergo longitudinal follow-up at least twice a year for the first few years following diagnosis. The treatment of PLCH is challenging and should be individualised. While there is no general consensus regarding the role of immunosuppression or chemotherapy in management, selected patients may experience improvement in lung function with therapy. Determination of BRAF or other mutations may assist with the development of an individualised approach to therapy. Patients with progressive disease should be referred to specialised centres and considered for a trial of pharmacotherapy or evaluated for transplantation.
肺朗格汉斯细胞组织细胞增生症（PLCH）是一种弥漫性肺部疾病，通常影响年轻成年吸烟者。PLCH 影响不同的肺区；细支气管、间质和肺血管功能障碍可能不同程度共存，导致不同的表型。对 PLCH 组织的分析已经确定了特定丝裂原活化蛋白激酶（BRAF 等）的激活突变。目前的共识是，PLCH 代表具有炎症特性的髓系肿瘤：髓系肿瘤细胞表现出表面 CD1a 表达，多达 50%的细胞携带激活的 BRAF 或其他 MAPK 突变。PLCH 可能与多系统疾病有关。全身正电子发射断层扫描有助于检测胸部以外的疾病。PLCH 的自然病程不可预测。在一些患者中，戒烟后疾病可能缓解或稳定。其他人则会出现进行性肺部疾病，通常伴有气流受限和肺血管功能障碍的证据。由于无法准确预测自然病程，因此重要的是，所有患者在诊断后的最初几年内至少每年进行两次纵向随访。PLCH 的治疗具有挑战性，应个体化。虽然在免疫抑制或化疗治疗管理中的作用方面尚无普遍共识，但选择的患者可能会因治疗而改善肺功能。BRAF 或其他突变的确定可能有助于制定个体化的治疗方法。进展性疾病患者应转至专门中心，并考虑进行药物治疗试验或评估移植。
