Department of Respiratory Medicine, Fukuoka University Hospital, Fukuoka, Japan.
Department of Pathology, Fukuoka University School of Medicine and Hospital, Fukuoka, Japan.
Histopathology. 2017 Dec;71(6):934-942. doi: 10.1111/his.13312. Epub 2017 Sep 22.
We occasionally encounter patients with idiopathic pulmonary fibrosis (IPF) who have similar imaging patterns to those of pleuroparenchymal fibroelastosis (PPFE) in the upper lung fields but are not diagnosed as having PPFE clinically. The aim of this study is to identify the clinicopathological features and intrapulmonary distribution of elastic fibres and collagen fibres in these patients.
We retrospectively reviewed the medical records of patients with a clinical diagnosis of IPF, and selected consecutive patients who underwent autopsy or pneumonectomy for lung transplantation. Patients with histologically confirmed PPFE were also reviewed for comparison. We quantified the collagen fibres and elastic fibres in each lobe as a percentage of the non-aerated lung area (collagen fibre score and elastic fibre score, respectively) in histological specimens by using whole-slide image analysis, and compared these scores between IPF and PPFE patients. In a total of 55 patients (IPF, 48; PPFE, 7), there were no significant differences in the collagen fibre scores between IPF and PPFE patients. The elastic fibre scores in the upper lobe in PPFE patients were significantly higher than those in IPF patients (23.5 versus 10.3, P = 0.005). However, it is of note that, in 12 of 48 IPF patients, the elastic fibre scores of the upper lobes were above the first quartile of those in PPFE patients.
IPF occasionally shows intense elastosis in the upper lobes, and such cases are histologically indistinguishable from PPFE. There seem to be histologically borderline cases between PPFE and IPF.
我们偶尔会遇到一些特发性肺纤维化（IPF）患者，他们的上肺野影像学表现与胸膜肺弹力纤维增生症（PPFE）相似，但临床上并未被诊断为 PPFE。本研究旨在确定这些患者的临床病理特征和肺内弹性纤维和胶原纤维的分布。
我们回顾性地审查了临床诊断为 IPF 的患者的病历，并选择了连续接受尸检或肺移植的患者。还回顾了经组织学证实为 PPFE 的患者进行比较。我们通过全切片图像分析，将组织学标本中每个肺叶的胶原纤维和弹性纤维分别作为未充气肺区的百分比（胶原纤维评分和弹性纤维评分）进行量化，并比较了 IPF 和 PPFE 患者之间的这些评分。在总共 55 名患者（IPF 48 例，PPFE 7 例）中，IPF 和 PPFE 患者之间的胶原纤维评分无显著差异。PPFE 患者的上叶弹性纤维评分明显高于 IPF 患者（23.5 比 10.3，P = 0.005）。然而，值得注意的是，在 48 例 IPF 患者中，有 12 例上叶的弹性纤维评分高于 PPFE 患者的第一四分位数。
IPF 偶尔在上叶显示强烈的弹力纤维增生，这些病例在组织学上与 PPFE 无法区分。PPFE 和 IPF 之间似乎存在组织学边界病例。
