PT - JOURNAL ARTICLE AU - Yoshihiro Nishiyama AU - Yuka Yamamoto AU - Kotaro Fukunaga AU - Hiroyuki Takinami AU - Yasuyoshi Iwado AU - Katashi Satoh AU - Motoomi Ohkawa TI - Comparative Evaluation of <sup>18</sup>F-FDG PET and <sup>67</sup>Ga Scintigraphy in Patients with Sarcoidosis DP - 2006 Oct 01 TA - Journal of Nuclear Medicine PG - 1571--1576 VI - 47 IP - 10 4099 - http://jnm.snmjournals.org/content/47/10/1571.short 4100 - http://jnm.snmjournals.org/content/47/10/1571.full SO - J Nucl Med2006 Oct 01; 47 AB - 67Ga scintigraphy has been used for years in sarcoidosis for diagnosis and the extent of the disease. However, little information is available on the comparison of 18F-FDG PET and 67Ga scintigraphy in the assessment of sarcoidosis. The purpose of this study was to compare the uptake of 18F-FDG and 67Ga in the evaluation of pulmonary and extrapulmonary involvement in patients with sarcoidosis. Methods: Eighteen patients with sarcoidosis were examined. 18F-FDG PET was performed at 1 h after injection of 185−200 MBq 18F-FDG. 67Ga whole-body planar and thoracic SPECT images were acquired 72 h after injection of 111 MBq 67Ga. We evaluated 18F-FDG and 67Ga uptake visually and semiquantitatively using standardized uptake values (SUVs) and the ratio of lesion to normal lumbar spine (L/N ratio), respectively. The presence of pulmonary and extrapulmonary lesions was evaluated histopathologically or by the radiologic findings. Results: Five patients had only pulmonary lesions, 12 patients had both pulmonary and extrapulmonary lesions, and 1 patient had only an extrapulmonary lesion. Both 67Ga planar and SPECT images detected 17 of 21 (81%) clinically observed pulmonary sites. The mean ± SD of the L/N ratio was 1.97 ± 1.09. 67Ga planar images detected 15 of 31 (48%) clinically observed extrapulmonary sites. The mean ± SD of the L/N ratio was 1.17 ± 0.33. 18F-FDG PET detected all 21 (100%) clinically observed pulmonary sites. The mean ± SD of the SUV was 7.40 ± 2.48. 18F-FDG PET detected 28 of 31 (90%) clinically observed extrapulmonary sites. The mean ± SD of the SUV was 5.90 ± 2.75. Conclusion: The results of this clinical study suggest that 18F-FDG PET can detect pulmonary lesions to a similar degree as 67Ga scintigraphy. However, 18F-FDG PET appears to be more accurate and contributes to a better evaluation of extrapulmonary involvement in sarcoidosis patients.