Wang Jing, Xie Liwu, Miao Yuchun, Liu Xiaoyu, Tang Yuan, Xi Yanfeng, Chang Jiang, Wu Yueqin, Jiang Lili
Department of Pathology, West China Hospital of Sichuan University, Chengdu, China.
Department of Pathology, Shanxi Tumor Hospital, Taiyuan, China.
Ann Transl Med. 2021 Feb;9(4):357. doi: 10.21037/atm-20-8141.
Adult pulmonary Langerhans cell histiocytosis (PLCH) is a rare form of Langerhans cell histiocytosis (LCH) that typically occurs in cigarette smokers. The clinical course of PLCH is unpredictable; the disease may resolve spontaneously, or lead to multi-organ failure and death. To better understand this idiopathic disease, we retrospectively overviewed a cohort of Asian patients with PLCHs.
Herein, we have provided detailed clinicopathological features and molecular findings of PLCHs in a Southwestern Chinese population, including the expressions of apoptotic protein P16, programmed cell death 1 (PD-1), and programmed cell death-ligand 1 (PD-L1). Importantly, the mutation was observed in this cohort.
In accordance with the follow up data, the cohort was subdivided into two groups, an isolated pulmonary group and extrapulmonary recidivism group. Among the isolated group, the participants were predominantly young males (<40 years old), with a history of smoking, respiratory symptoms (cough and difficulty breathing), showed more cystic lesions in computed tomography (CT) scanning, had more cellular Langerhans granulomas under the microscope, overexpression of P16 (66.7%), high PD-1 (100%) and low PD-L1 (33.3%) expressions, and no mutation was detected. In contrast, the extrapulmonary recidivism group showed significantly older age (>40 years old), recurrent spontaneous pneumothorax, more nodular changes in CT scanning, more interstitial fibrosis histologically, expression rates of 100% of P16, 66.7% of PD-1, and 33.3% of PD-L1; and importantly, mutation was detected in 33.3% of this subdivision.
We found that adult PLCH might consist of two distinct groups: an isolated form and extrapulmonary recidivism PLCH. Overexpression of P16 could be a diagnostic biomarker for PLCH. An extremely low mutation rate of the gene in adult PLCH in our cohort indicated that there might be other pathogeneses for this disease among Asian patients.
成人肺朗格汉斯细胞组织细胞增多症（PLCH）是朗格汉斯细胞组织细胞增多症（LCH）的一种罕见形式，通常发生于吸烟者。PLCH的临床病程不可预测；该疾病可能自发缓解，或导致多器官衰竭和死亡。为了更好地了解这种特发性疾病，我们对一组亚洲PLCH患者进行了回顾性研究。
在此，我们提供了中国西南地区人群中PLCH的详细临床病理特征和分子研究结果，包括凋亡蛋白P16、程序性细胞死亡蛋白1（PD-1）和程序性细胞死亡配体1（PD-L1）的表达情况。重要的是，在该队列中观察到了 突变。
根据随访数据，该队列被分为两组，即单纯肺部病变组和肺外复发组。在单纯肺部病变组中，参与者主要为年轻男性（<40岁），有吸烟史，有呼吸道症状（咳嗽和呼吸困难），计算机断层扫描（CT）显示更多囊性病变，显微镜下有更多细胞性朗格汉斯肉芽肿，P16过表达（66.7%），PD-1高表达（100%），PD-L1低表达（33.3%），且未检测到 突变。相比之下，肺外复发组患者年龄明显较大（>40岁），反复自发性气胸，CT扫描有更多结节样改变，组织学上有更多间质纤维化，P16、PD-1和PD-L1的表达率分别为100%、66.7%和33.3%；重要的是，该亚组中33.3%的患者检测到 突变。
我们发现成人PLCH可能由两个不同的组组成：单纯型和肺外复发型PLCH。P16过表达可能是PLCH的诊断生物标志物。我们队列中成人PLCH患者 基因的极低突变率表明，亚洲患者中该疾病可能存在其他发病机制。
