Takashi Yamashita,Kensuke Takei,Yuta Matsubayashi,Kiyomichi Mizuno,Katsuyuki Asai
Intrapleural findings of pulmonary light‐chain deposition disease Yamashita et al.
light‐chain deposition disease,rare lung disease,thoracoscopy
Key message Light‐chain deposition disease is accompanied not only by characteristic CT findings but also by characteristic gross findings of the visceral pleura. Medical thoracoscopy could diagnose LCDD by the findings of the thoracic cavity.
Intrapleural findings of pulmonary light‐chain deposition disease Yamashita et al.

Light‐chain deposition disease is accompanied not only by characteristic CT findings but also by characteristic gross findings of the visceral pleura. Medical thoracoscopy could diagnose LCDD by the findings of the thoracic cavity.

Light chain deposition disease (LCDD) is a rare multisystem disorder characterized by deposition of monoclonal light chains in any organ, with almost invariable renal involvement, but potential pulmonary involvement. A 70‐year‐old male underwent left upper lobectomy and lymph node dissection for squamous cell carcinoma of the lung. Although no pleural nodules were identified preoperatively, thoracotomy revealed numerous 1–3 mm nodules on the lung surface. These nodules were found in the visceral pleura but there were no nodules in the parietal pleura (Figure 1, Video 1). The postoperative pathological diagnosis of the nodules was LCDD (Figure 2). Computed tomography (CT) retrospectively showed small nodules mimicking pleural dissemination (Figure 3) and small cysts with vessels in the wall and central traversing vessels that are features of pulmonary LCDD (Figure 4). The patient had been diagnosed with chronic kidney disease, attributed to hypertensive nephropathy, 2 years prior to surgery, with progression to stage G4 at the time of surgery, and to dialysis 1 year post‐surgery. Earlier recognition of chest CT findings suggestive of pulmonary LCDD, followed by investigation such as medical thoracoscopy, may have enabled earlier diagnosis and treatment of renal involvement by LCDD.

Takashi Yamashita conceived this case presentation and drafted the manuscript. Takashi Yamashita, Yuta Matsubayashi, Kiyomichi Mizuno, and KA participated in the design of this case presentation and in the acquisition, analysis and interpretation of data. Takashi Yamashita, Kensuke Takei, and Katsuyuki Asai participated in the treatment of the patient. All authors read and approved the final manuscript.

None declared.

The authors declare that appropriate written informed consent was obtained for the publication of this manuscript and accompanying images.