Visceral pleural biopsy under medical thoracoscopy for the diagnosis of lung adenocarcinoma

Medical thoracoscopy is a minimally invasive single‐port endoscopic technique that provides direct visualization of the pleural surface and allows for diagnostic procedures. The diagnostic yield of medical thoracoscopy is high and is generally based on parietal pleural biopsy findings. Pleural biopsies are valuable for a diagnosis. However, visceral pleural biopsies are uncommon because of the risk of prolonged air leak. In this study, we report a rare case of the successful diagnosis of lung adenocarcinoma, based on the findings of visceral pleural biopsy under medical thoracoscopy. To avoid lung injury and pneumothorax, we focused on maintaining the thoracoscope and biopsy forceps in a straight angle as much as possible. While looking straight ahead at the visceral pleural nodule as closely as possible, biopsy samples were carefully obtained while confirming that the normal lung was not held. With careful consideration, visceral pleural biopsies may expand the diagnostic capability of medical thoracoscopy.