An Autopsied Case of Malignant Sarcomatoid Pleural Mesothelioma in Which Chest Pain Developed Several Months Earlier without Abnormality on Imaging.

The patient experienced chest pain for about 7 months, but a diagnosis could not be made until after death. He was diagnosed with malignant sarcomatoid pleural mesothelioma on autopsy. In this case report, difficult aspects of the diagnosis are discussed. The 70-year-old Japanese man was a driver who transported ceramic-related products. Right chest pain developed in July 2013, but no abnormality was detected on a chest computed tomography (CT) performed in September 2013, and the pain was managed as right intercostal neuralgia. A chest CT performed in late October 2013 revealed a right pleural effusion, and the patient was referred to our hospital in early November 2013. Thoracentesis was performed, but the cytology was negative, and no diagnosis could be made. Close examination was postponed because the patient developed a subarachnoid hemorrhage. He underwent (18)F-fluorodeoxyglucose positron emission tomography ((18)F-FDG PET) after discharge from the neurosurgery department, and extensive right pleural thickening and (18)F-FDG accumulation in this region were observed. Based on these findings, malignant pleural mesothelioma was suspected, and a thoracoscopy was performed under local anesthesia in early December 2013, but no definite diagnosis could be made. The patient selected best supportive care and died about 7 months after the initial development of right chest pain. The disease was definitively diagnosed as malignant sarcomatoid pleural mesothelioma by a pathological autopsy. When chronic chest pain of unknown cause is observed and past exposure to asbestos is suspected, actions to prevent delay in diagnosis should be taken, including testing for suspicion of malignant pleural mesothelioma.

Required thoracic drainage through the respiratory tract during transbronchial biopsy using EBUS-GS.

A 71-year-old woman was referred to our department due to an abnormal chest shadow. Imaging revealed a pulmonary nodule shadow in the left S6 segment, multiple small nodule shadows in the left pleura, and left pleural effusion. Transbronchial biopsy using endobronchial ultrasonography (EBUS) with a guide sheath was conducted. EBUS showed the probe of the sheath located in the lesion and biopsy was performed in this area. A yellow turbid fluid appeared in the sheath and vacuum aspiration resulted in collection of 200 mL of this fluid. We suspected that drainage occurred because the sheath tip had ruptured the pleural cavity. The pathological diagnosis was adenocarcinoma. It is likely that the EBUS images reflected pleural effusion adjacent to the lesion, and that the complication occurred because the biopsy was performed without awareness of these findings. This complication may be prevented by closer examination of echo findings and rotation of the X-ray source to ensure performance of the biopsy directly under the pleura.