Histiocytic pleural effusion: the strong clue to malignancy

Abstract

Background There have been many studies on the clinical characteristics of neutrophilic, lymphocytic, and/or eosinophilic pleural effusion. While caring for patients with pleural effusion, we found that histiocytic pleural effusion (HisPE) was not uncommon. However, few studies have explored HisPE. The purpose of the present study was to determine the clinical characteristics and etiologies of HisPE. Methods In this retrospective study, HisPE was defined as pleural fluid white blood cells comprised of ≥ 50% histiocytes. Using a clinical data warehouse, patients with HisPE among all patients aged >18 years who underwent thoracentesis and pleural fluid analysis between January 2010 and December 2019 at Ulsan University Hospital were enrolled. A total of 295 (9.0%) of 3279 patients who underwent thoracentesis were identified as HisPE patients. Among them, 201 with exudative HisPE were included. Clinical characteristics and etiologies were extracted from medical records and analyzed. Results Among the 201 patients with exudative HisPE, the major causes were malignant pleural effusion (n = 102 [50.7%]), parapneumonic effusion (n = 9 [4.5%]), and tuberculous pleurisy (n = 9 [4.5%]). In the 102 patients with malignant pleural effusion, the main types of cancer were lung (n = 42 [41.2%]), breast (n = 16 [15.7%]), and stomach cancer (n = 11 [10.8%]). Among lung cancers, adenocarcinoma (n = 34 [81.0%]) was the most common histology. Conclusions The leading cause of exudative HisPE was malignancy, particularly lung cancer. Physicians should consider the possibility of malignant disease if histiocytes are predominantly present in pleural effusion.

Exosomal miRNA-profiling of pleural effusion in lung adenocarcinoma and tuberculosis

“…It also plays an essential role in the adhesion of macrophages, neutrophils, and monocytes (41,42). A previous study indicated that macrophages were associated with MPE and pleural metastasis of cancer triggered immune responses (43). We hypothesized that ITGAM was implicated in the development of MPE by tumor immune response, even though its significance in the PE of lung cancer is yet unknown.…”

Clinical implications of pleural effusion following left ventricular assist device implantation

“…Our findings showed that CPB time was not associated with PE in either the TD or no TD group. Histiocytic pleural effusion (HisPE) is defined as a PE in which histocytes account for more than 50% of all white blood cells [ 22 ]. In this study, four of six (66%) cases of early PE and all four (100%) cases of late PE met the classification of HisPE.…”

Pleurodesis

“…However, a non-negligible percentage, between 5% to 10% of malignant pleural effusions, are transudates considered as a superposition of both or false transudates [61]. They can also occur as histiocytic [62] or neutrophilic exudates [63], the latter being a marker of poor prognosis [64]; therefore, it is important to keep this possibility in mind when performing thoracentesis [54,65,66].…”