胸腔鏡下に観察しえた肺アミロイドーシスの1例

Pulmonary Amyloidosis Observed by Thoracoscopy：Report of a Case

はじめに　多発肺結節の経過観察中に増大傾向を示す結節を認めた場合，悪性疾患が鑑別となる．われわれは，原発性肺癌の合併を疑い，手術によりアミロイドA（AA）型アミロイドーシスの診断にいたった症例を経験した．鏡視下にアミロイド結節を観察した症例の報告は少なく，術中所見とともに報告する．

The case is an 80-year-old woman with Sjögren’s syndrome. During the follow-up of multiple pulmonary nodules, an enlarged nodule was observed in the peripheral of the right S3 interlobar region. Fluorodeoxyglucose-positron emission tomography （FDG-PET） showed FDG accumulation only in the S3 nodule, which led to suspicion of primary lung cancer. Because of its difficult location to reach by bronchoscopy, a right lung S3 segmentectomy was performed. Intraoperative findings revealed a hard yellowish-white nodule just below the pleura. Pathological examination showed that the nodule consisted of an acidophilic structureless material, which was positive for Congo red staining and disappeared after permanganate treatment. Based on the above findings, we diagnosed amyloid A （AA）-type amyloidosis. In this case, the nodule was located just below the pleura and we could observe it by thoracoscopy. There have been few reports of thoracoscopic observation of pulmonary amyloidosis, and we report with intraoperative findings.