PT - JOURNAL ARTICLE AU - Tomomi Nobashi AU - Takeshi Kubo AU - Yuji Nakamoto AU - Tomohiro Handa AU - Sho Koyasu AU - Takayoshi Ishimori AU - Michiaki Mishima AU - Kaori Togashi TI - <sup>18</sup>F-FDG Uptake in Less Affected Lung Field Provides Prognostic Stratification in Patients with Interstitial Lung Disease AID - 10.2967/jnumed.116.174946 DP - 2016 Dec 01 TA - Journal of Nuclear Medicine PG - 1899--1904 VI - 57 IP - 12 4099 - http://jnm.snmjournals.org/content/57/12/1899.short 4100 - http://jnm.snmjournals.org/content/57/12/1899.full SO - J Nucl Med2016 Dec 01; 57 AB - This study evaluated the clinical significance of 18F-FDG PET/CT in patients with interstitial lung disease (ILD), by investigating the relationships between 18F-FDG PET/CT parameters and clinical indicators and by evaluating the prognostic implications of 18F-FDG PET/CT results. Methods: Ninety patients (51 men, 39 women; mean age, 55.4 y; age range, 26–78 y) with ILD who underwent 18F-FDG PET/CT were retrospectively analyzed. SUVmean was defined as the mean SUV of the less-affected lung field, SUVTF as adjusted SUVmean using tissue fraction (TF), and CTmean as the mean attenuation of the corresponding region of interest on high-resolution CT. SUVmean, SUVTF, and CTmean were compared in the 90 ILD patients and in 15 age- and sex-matched controls. Correlations of SUVmax, SUVmean, SUVTF, and CTmean with clinical indicators, including estimated percentage of forced vital capacity (%FVC), estimated percentage of diffusion capacity of the lungs for carbon monoxide (%DLco), sialylated carbohydrate antigen Krebs von den Lungen-6 (KL-6), surfactant protein D (SP-D), C-reactive protein (CRP), lactate dehydrogenase (LDH), and ILD-sex-age-physiology (GAP) index, were evaluated using the Spearman rank correlation test and the Tukey–Kramer test. A Cox proportional hazards model was used for univariate and multivariate analyses of factors associated with lung transplantation-free survival. Results: SUVmean, SUVTF, and CTmean were significantly higher in ILD patients than in healthy controls, except for CTmean in patients with a nonusual interstitial pneumonia pattern. SUVmean and CTmean were significantly correlated with %FVC, %DLco, KL-6, and SP-D; SUVTF was significantly correlated with %DLco, KL-6, SP-D, and LDH; and SUVmax was weakly correlated with KL-6 and CRP. Univariate analysis showed that SUVmean, SUVTF, sex, %FVC, %DLco, KL-6, and ILD-GAP index were significantly prognostic of lung transplantation-free survival; and multivariate analysis showed that SUVmean and ILD-GAP index were independently prognostic of lung transplantation-free survival. A higher SUVmean indicated a poorer prognosis, especially in patients with moderate risk based on ILD-GAP index. Conclusion: SUVmean was significantly but moderately correlated with clinical indicators, providing independent prognostic information in patients with ILD. 18F-FDG PET/CT may be helpful for monitoring and risk stratification of ILD patients.