Purpose: Sarcoidosis is a multisystem granulomatous disorder, most frequently involving the lungs, skin, or eyes. Somatostatin receptor scintigraphy (SRS) can visualize sarcoid granulomas through binding of a radionuclide-coupled somatostatin analog to somatostatin receptors that are expressed in sarcoidosis. Uptake and patterns on SRS were studied and correlated to clinical and conventional findings.
Patients and methods: Data of 218 SRSs undertaken for the analysis of potential sarcoidosis were studied. These scintigraphies were retrospectively studied on intensity uptake degrees and localization of sarcoidosis-associated lesions, and compared with conventional radiological techniques (chest x-ray and CT).
Results: In all but 1 of the 175 evaluable patients, SRS demonstrated uptake. In patients with thoracic sarcoidosis-associated lesions, SRS improved the yield of visualization of chest x-ray in 20 (36%) and CT in 7 (32%) of histologically unproven patients, and in 31 (30%) and 8 (14%) of the histologically proven patients, respectively. Mediastinal lesions together with either eye, salivary glands, clavicular, or hilar localizations were most frequent demonstrated on SRS and constituted characteristic patterns. Exclusive extrapulmonary disease was found in 6% of the patients.
Conclusions: Somatostatin receptor scintigraphy enhances the yield of investigations in sarcoidosis patients and therefore provides a useful and sensitive imaging technique to monitor organ involvement and therapeutic efficacy in patients with sarcoidosis.