Abstract

BIANCO, C et al. PET/TC en sarcoidosis asociada a enfermedad oncológica. Rev. argent. radiol. [online]. 2017, vol.81, n.2, pp.92-99. ISSN 1852-9992.  http://dx.doi.org/10.1016/j.rard.2017.03.001.

Purposes: To describe the radiological findings of sarcoidosis or sarcoid-like reactions in cancer patients being monitored by positron emission computed tomography (PET/CT). Materials and methods: A retrospective analysis was performed on 18 PET/CT studies performed over 3 years in patients with lymphomas and solid tumours who presented with hypermetabolic hiliar-mediastinal adenopathies. The morphological pattern of these adenopathies, the distribution, and in some cases the association with pulmonary nodules, might suggest sarcoidosis as a differential diagnosis. Results: Oncological diseases corresponded to breast (4), prostate (3), ovary (2), and others (9). The adenopathies were classified in 7 of the 18 patients as benign after histological confirmation of sarcoidosis, anthracosis or sarcoid-like reaction. The evolutionary behaviour in 5 patients was compatible with benign lesions. The biopsy of 2 patients indicated secondary lesions and malignancy was confirmed by the evolution of the 4 remaining cases. There was a total of 12 (66%) benign lesions. Discussion: Sarcoidosis must be suspected in the presence of hypermetabolic hiliar-mediastinal adenopathies with a characteristic morphological pattern and pulmonary changes. However, biopsy is required to rule out oncological recurrence. The use of new PET/CT markers for differential diagnosis represents a challenge. Aminoacid synthesis tracers such as ¹⁸F-fluorothymidine (FLT) and ¹⁸F-fluoromethyltyrosine (FMT) are useful in the differentiation between malignancy and granulomatous diseases in oncologic patients. Conclusion: The differential diagnosis of sarcoidosis should be considered in the presence of bilateral symmetric mediastinal hilum lymphadenopathies.

Keywords : Lymph nodes; Clinical Oncology; Sarcoidosis; Tomography, Emission-Computed.