[Pulmonary Amyloidosis Observed by Thoracoscopy:Report of a Case]

Area of Science:

• Pulmonology
• Pathology
• Medical Imaging

Background:

• Sjögren's syndrome can be associated with various pulmonary complications.
• Pulmonary nodules require careful evaluation to differentiate between benign and malignant conditions.
• Amyloidosis, particularly AA-type, is a rare cause of pulmonary nodules.

Purpose of the Study:

• To report a unique case of pulmonary amyloidosis mimicking lung cancer.
• To describe the diagnostic process and intraoperative findings of a thoracoscopically observed pulmonary nodule.
• To contribute to the limited literature on thoracoscopic management of pulmonary amyloidosis.

Main Methods:

• Case presentation of an 80-year-old woman with Sjögren's syndrome and a pulmonary nodule.
• Utilized Fluorodeoxyglucose-Positron Emission Tomography (FDG-PET) for nodule characterization.
• Performed right lung S3 segmentectomy due to difficult bronchoscopic access.
• Conducted pathological examination including Congo red staining and permanganate treatment.

Main Results:

• FDG-PET indicated increased metabolism in the S3 nodule, raising suspicion for primary lung cancer.
• Intraoperative findings revealed a hard, yellowish-white subpleural nodule.
• Pathological examination confirmed AA-type amyloidosis through characteristic staining and reactivity.
• The nodule was successfully resected via segmentectomy.

Conclusions:

• Pulmonary nodules in patients with Sjögren's syndrome warrant thorough investigation for rare conditions like AA-type amyloidosis.
• Thoracoscopic observation can be valuable for diagnosing and managing peripheral pulmonary nodules.
• This case underscores the importance of pathological confirmation in diagnosing pulmonary amyloidosis.