Fig. 1
From: Histiocytic pleural effusion: the strong clue to malignancy
Microscopic image of histiocytes in pleural fluid (Wright-Giemsa stain, ×1000). Histiocytes can be observed as single or grouped cells, and their sizes vary considerably, ranging from approximately 15 to 100 μm in diameter. The nucleus (a) is located on one side of the cytoplasm in a distorted form or a kidney shape. The cytoplasm contains vacuoles (b) and ingested red blood cells (c) and has an unclear boundary