Somatostatin receptor scintigraphy and gallium scintigraphy in patients with sarcoidosis

Abstract

Somatostatin receptor scintigraphy (SRS) has been shown to reveal sarcoidosis sites. The aim of this study was to prospectively compare SRS and gallium scintigraphy in the evaluation of pulmonary and extrapulmonary involvement in patients with proven sarcoidosis.

Methods: Eighteen patients with biopsy-proven sarcoidosis were included. Nine were or recently had been receiving steroid therapy at the time of the examination. Planar gallium scintigraphy (head, chest, abdomen, and pelvis) and thoracic SPECT were performed at 48-72 h after injection of a mean dose of 138 +/- 21 MBq 67Ga. Planar SRS and thoracic SPECT were performed at 4 and 24 h after injection of a mean dose of 148 +/- 17 MBq 111n-pentetreotide.

Results: Gallium scintigraphy found abnormalities in 16 of 18 patients (89%) and detected 64 of 99 clinically involved sites (65%). SRS found abnormalities in 18 of 18 patients and detected 82 of 99 clinically involved sites (83%). Of the 9 treated patients, gallium scintigraphy found abnormalities in 7 (78%), detecting 23 of 39 clinically involved sites (59%), whereas SRS found abnormalities in 9, detecting 32 of 39 clinically involved sites (82%).

Conclusion: This study suggests that, compared with gallium scintigraphy, SRS appears to be accurate and contributes to a better evaluation of organ involvement in sarcoidosis patients, especially those treated with corticosteroids.