Early and delayed diuretic 18F-FDG PET/CT in diagnosis of renal cell carcinoma

Abstract

Objective To investigate the potential value of delayed diuretic 18F-FDG PET/CT scan for differentiating renal lesions. Methods A total of 30 patients with renal lesions underwent 18F-FDG PET/CT early-delayed imagings before surgical treatment or transrectal needly biopsy.After attenuation correction and iterative reconstruction, PET image datas were analyzed semi-quantiatively by measuring maximum standardized uptake values (SUVmax)in renal lesions. Results There were 25 cases of renal cell carcinoma (RCC), 1 case of primary benign space occupying, 1 case of inflammatory lesions and 3 cases of metastatic tumor.The SUVmax value of early imaging of RCC was compared with that of delayed diuretic SUVmax (P=0.004). Early PET/CT imaging sensitivity was 68.0%, specificity was 100%, accuracy was 73.3%, positive predictive value was 100% and negative predictive value was 38.5%.The sensitivity of delayed diuretic imaging was 92.0%, specificity was 100%, accuracy was 93.3%, positive predictive value was 100% and negative predictive value was 71.4%.Linear correlation analysis was performed for SUVmax value of early imaging and SUVmax value of delayed diuretic imaging and lesion diameter, respectively.Early imaging r=0.141, P=0.502, delayed diuretic imaging r=0.168, P=0.373. Conclusion The 18F-FDG PET/CT early diuretic delayed imaging has certain diagnostic value for renal tumors, and is helpful for the preliminary pathological grade and staging of renal malignant lesions. Key words: Renal cell carcinoma; Standard uptake value; PET/CT; Renal carcinoma; Maximum standardized uptake value