title: Lung amyloid nodule detected by 99mTc-aprotinin scintigraphy.
abstract: We present a case in which an amyloid lung nodule was diagnosed preoperatively by amyloid scintigraphy (99m)Tc-aprotinin. A 65-year-old man complained of marked weight loss (9 kg) over a period of 6 months. An abnormal shadow in the middle field of the right lung was detected on chest X-ray, corresponding to a 16-mm nodule in the right middle lobe on thoracic computed tomography (CT). Total protein and immunoglobulin G levels were elevated to 8.3 and 2245 mg/dl, respectively, but other blood tests including several tumor marker levels and Cryptococcus antibodies were all within normal range. Fluorodeoxyglucose positron emission tomography showed no uptake by the lung nodule, so lung amyloidosis was considered as differential diagnosis. To avoid risk of bleeding on bronchoscopy, noninvasive amyloid scintigraphy using (99m)Tc-aprotinin was first performed. A nodular, abnormal accumulation was observed in the right middle lung lobe. Diagnostic imaging strongly suggested amyloidosis, so video-assisted thoracic surgery was performed rather than bronchoscopy. Pathological samples showed positive staining with Congo red, and A-λ amyloidosis was diagnosed on the basis of immunostaining. Scintigraphy using (99m)Tc-aprotinin offers a useful, noninvasive method for assessing lung amyloidosis.
authors.affiliation: Department of Respiratory Medicine, National Center for Global Health and Medicine, Tokyo, Japan. satishii@hosp.ncgm.go.jp
authors.forename: Satoru
authors.initials: S
authors.lastname: Ishii
authors.forename: Kazuo
authors.initials: K
authors.lastname: Kubota
authors.forename: Ryogo
authors.initials: R
authors.lastname: Minamimoto
authors.forename: Rikiya
authors.initials: R
authors.lastname: Kouketu
authors.forename: Miyako
authors.initials: M
authors.lastname: Morooka
authors.forename: Shigeo
authors.initials: S
authors.lastname: Kawai
authors.forename: Yuichiro
authors.initials: Y
authors.lastname: Takeda
authors.forename: Nobuyuki
authors.initials: N
authors.lastname: Kobayashi
authors.forename: Haruhito
authors.initials: H
authors.lastname: Sugiyama
mesh_terms: D000368:Aged; D000686:Amyloidosis / Q000000981:diagnostic imaging* / Q000473:pathology / Q000503:physiopathology / Q000601:surgery; D007611:Aprotinin; D006801:Humans; D008171:Lung Diseases / Q000000981:diagnostic imaging* / Q000473:pathology / Q000503:physiopathology / Q000601:surgery; D008297:Male; D015609:Organotechnetium Compounds; D057234:Preoperative Period; D011877:Radionuclide Imaging
chemical_list: D015609:Organotechnetium Compounds; C041381:technetium Tc 99m aprotinin; D007611:Aprotinin