title: FDG-PET/CT of sarcoidosis and sarcoid reactions following antineoplastic treatment.
abstract: Sarcoidosis or sarcoid reactions, which appear as FDG-avid lesions in oncologic patients, need to be differentiated from disseminated malignancies. We aimed to promote awareness of development of sarcoidosis or sarcoid reactions after antineoplastic therapy to avoid diagnostic errors with FDG-PET/CT findings and assess the utility of FDG-PET/CT for follow-up. We retrospectively reviewed radiological reports of FDG-PET/CT scans performed between January 2009 and December 2011. Among oncologic patients with more than 2 FDG-PET/CT scans, those with nearly symmetrical increases in FDG uptake in the hilar or mediastinal lymph nodes were identified, and those with known sarcoidosis, concurrent diagnoses of sarcoidosis with malignancy, or histopathologically proven malignancies were excluded. Then, only those cases were selected for which sarcoidosis or sarcoid reactions were diagnosed. Four of 376 oncologic cases met the criteria. At 9 months to 6 years after antineoplastic therapy, abnormal FDG uptakes were observed in the hilar, mediastinal, abdominal, pelvic, and inguinal nodes, and/or spleen and lung parenchyma with SUVmax up to 17.7. On the basis of these findings, 1 patient received anticancer chemotherapy because of tumor recurrence suspicion. A gradual decrease in FDG uptake was observed on subsequent PET/CT scans. Sarcoidosis or sarcoid reactions should be considered in differential diagnosis of oncologic patients who have developed FDG-avid lesions any time after antineoplastic therapy. FDG-PET/CT can be used for follow-up in nondiagnostic situations to detect decreases in FDG uptake due to presence of sarcoidal granulomas.
authors.affiliation: Department of Nuclear Medicine and Radiology, Institute of Development, Aging and Cancer, Tohoku University, 4-1 Seiryomachi, Aoba-ward, Sendai, 980-8575 Japan.
authors.forename: Kentaro
authors.initials: K
authors.lastname: Inoue
authors.forename: Ryoi
authors.initials: R
authors.lastname: Goto
authors.forename: Hideo
authors.initials: H
authors.lastname: Shimomura
authors.forename: Hiroshi
authors.initials: H
authors.lastname: Fukuda
keywords: Cancer; FDG; Lymphadenopathy; Malignancy; PET; Sarcoid reactions; Sarcoidosis
references.citation: Gen Thorac Cardiovasc Surg. 2010 Aug;58(8):434-7
references.pmid: 20703868
references.citation: Clin Nucl Med. 2007 Jul;32(7):569-71
references.pmid: 17581351
references.citation: Clin Lymphoma Myeloma Leuk. 2010 Aug;10(4):241-7
references.pmid: 20709659
references.citation: Jpn J Thorac Cardiovasc Surg. 2005 Apr;53(4):196-8
references.pmid: 15875553
references.citation: Clin Radiol. 2009 Jul;64(7):675-81
references.pmid: 19520211
references.citation: Chest. 2007 Apr;131(4):1019-27
references.pmid: 17426205
references.citation: Eur J Nucl Med Mol Imaging. 2008 Aug;35(8):1537-43
references.pmid: 18418595
references.citation: J Cardiothorac Surg. 2008 Feb 25;3:8
references.pmid: 18298864
references.citation: Chest. 1995 Mar;107(3):605-13
references.pmid: 7874925
references.citation: Chest. 1995 Nov;108(5):1472-4
references.pmid: 7587468
references.citation: Ann Oncol. 1998 Mar;9(3):321-5
references.pmid: 9602267
references.citation: Surg Today. 2012 Feb;42(3):259-63
references.pmid: 22160357
references.citation: APMIS. 1991 Mar;99(3):282-90
references.pmid: 1708267
references.citation: Radiology. 1996 Jul;200(1):255-61
references.pmid: 8657922
references.citation: Ann Oncol. 2001 Oct;12(10):1485-8
references.pmid: 11762823
references.citation: Am J Respir Crit Care Med. 1999 Aug;160(2):736-55
references.pmid: 10430755
references.citation: Am J Surg. 2009 May;197(5):629-32; discussion 632
references.pmid: 19321155
references.citation: J Clin Oncol. 2005 Jan 20;23(3):640-1
references.pmid: 15659510
references.citation: Ann Thorac Surg. 2010 Dec;90(6):2031-3
references.pmid: 21095358
references.citation: Chest. 1990 Nov;98(5):1300-2
references.pmid: 2225992
references.citation: J Nucl Med. 2008 Sep;49(9):1429-36
references.pmid: 18765585
references.citation: Mol Imaging Biol. 2009 Jul-Aug;11(4):224-8
references.pmid: 19333656
references.citation: Rev Med Interne. 2008 Jan;29(1):39-45
references.pmid: 18054124
references.citation: Clin Dermatol. 2007 May-Jun;25(3):326-33
references.pmid: 17560310
references.citation: J Clin Oncol. 2005 Jan 20;23(3):641-3
references.pmid: 15659511
references.citation: Chest. 2007 Dec;132(6):1949-53
references.pmid: 17925421
references.citation: Radiographics. 1999 Jan-Feb;19(1):61-77; quiz 150-1
references.pmid: 9925392
references.citation: N Engl J Med. 2007 Nov 22;357(21):2153-65
references.pmid: 18032765
references.citation: Cancer Treat Rev. 1986 Sep;13(3):147-56
references.pmid: 3536088