Journal Information
Vol. 56. Issue 3.
Pages 174-175 (March 2020)
Download PDF
More article options
Vol. 56. Issue 3.
Pages 174-175 (March 2020)
Clinical Image
Full text access
Lambda Sign: Sarcoidosis
El signo lambda: sarcoidosis
Yu Matsumotoa,
Corresponding author

Corresponding author.
, Masahiro Yamasakia, Naoko Matsumotoa, Masaya Taniwakia, Noboru Hattorib
a Department of Respiratory Disease, Hiroshima Red Cross Hospital & Atomic Bomb Survivors Hospital, Naka-ku, Hiroshima, Japan
b Department of Molecular and Internal Medicine, Institute of Biomedical & Health Sciences, Hiroshima University, Minami-ku, Hiroshima, Japan
This item has received
Article information
Full Text
Download PDF
Figures (1)
Full Text

A 43-year-old woman was referred to our hospital with bilateral hilar lymphadenopathy on chest radiography. She was examined by enhanced computed tomography scan, and bilateral hilar and mediastinal lymphadenopathy was detected. [18F]-fluorodeoxyglucose (FDG) positron emission tomography (PET) showed a high uptake in the above-mentioned lymphadenopathy, demonstrated by the so-called “lambda (λ) sign” (Fig. 1); therefore, sarcoidosis was suspected. A granuloma in the lymph node specimen and a high CD4/CD8 ratio of BAL were detected on endobronchial ultrasound-guided needle aspiration of the mediastinal lymph node and bronchoalveolar lavage (BAL) fluid examination. Therefore, she was diagnosed with sarcoidosis. As no sarcoid lesions were detected in other organs, such as heart, eyes, and skin, she was followed-up with no treatment.

Fig. 1.

(A) Chest radiograph showing bilateral hilar lymphadenopathy. (B) Chest computed tomography scan showing the bilateral hilar and mediastinal lymphadenopathy. (C) [18F]-fluorodeoxyglucose positron emission tomography scan showing the so-called “lambda (λ) sign”, indicating a high uptake in the bilateral hilar and mediastinal lymphadenopathy with a prominent right paratracheal region.


The lambda sign means that a bilateral hilar and mediastinal lymphadenopathy with a prominent right paratracheal region on gallium scintigraphy gives the impression of an uptake pattern shaped as a “λ”.1 This sign shows high specificity for sarcoidosis.1 In a recent report, the lambda sign was also observed on an [18F]-FDG PET.2 It has remarkable sensitivity in detection of occult disease sites, hence providing biopsy guidance.3 A typical lambda sign supports the diagnosis of sarcoidosis and reinforces the indication to perform appropriate examinations.

S.B. Sulavik, R.P. Spencer, D.A. Weed, H.R. Shapiro, S.T. Shiue, R.J. Castriotta.
Recognition of distinctive patterns of gallium-67 distribution in sarcoidosis.
J Nucl Med, 31 (1990), pp. 1909-1914
M.Ö. Öksüz, M.K. Werner, P. Aschoff, C. Pfannenberg.
18F-FDG PET/CT for the diagnosis of sarcoidosis in a patient with bilateral inflammatory involvement of the parotid and lacrimal glands (panda sign) and bilateral hilar and mediastinal lymphadenopathy (lambda sign).
Eur J Nucl Med Imaging, 38 (2011), pp. 603
D. Israel-Biet, D. Valeyre.
Diagnosis of pulmonary sarcoidosis.
Curr Opin Pulm Med, 19 (2013), pp. 510-515
Copyright © 2019. SEPAR
Archivos de Bronconeumología
Article options

Are you a health professional able to prescribe or dispense drugs?