Advantages of CTU and MRU include the ability to visualize small masses directly, identify focal wall thickening, and distinguish nonspecific filling defects such as enhancing tumor versus nonenhancing calculi or blood clots. Additionally, CTU and MRU can assess nonfunctioning/obstructed kidneys that would not excrete contrast medium required for excretory urography [5,37]. Based on these strengths, Jinzaki et al [37] concluded that CTU should be considered as the initial examination for the evaluation of patients at high risk for upper urinary tract UC, and Cohan et al [39] concluded that CTU can detect many more bladder cancers than excretory urography. FDG-PET/CT Skull Base to Mid-Thigh FDG-PET/CT is not ideal for evaluating the urinary collecting system due to FDG excretion in urine but can effectively assess nodal and metastatic disease. A study by Goodfellow et al [90] involving 233 patients found that CT had a sensitivity and specificity of 45% and 98%, respectively, in detecting pelvic lymph node metastases. FDG- Pretreatment Staging of Urothelial Cancer PET/CT increased sensitivity to 69%, with a slight reduction in specificity to 95%. In a prospective study of 25 patients by Nayak et al [91], FDG-PET/CT had a sensitivity of 78% compared with CT, with a sensitivity of 44% in detecting positive lymph nodes for metastases on histopathology. Other studies have reported the sensitivity of FDG-PET/CT for lymph node metastasis detection ranging from 47% to 56% and the specificity ranging from 93% to 98%, with specificity usually slightly lower than for CT [92]. Pichler et al [93] retrospectively analyzed 70 patients with bladder cancer staged with FDG-PET/CT before radical cystectomy and found that using an 8-mm cutoff, CT had a specificity of 92%, whereas FDG-PET alone had a sensitivity, specificity, and accuracy of 55%, 90%, and 84%, respectively.
Pretreatment Staging of Urothelial Cancer. Advantages of CTU and MRU include the ability to visualize small masses directly, identify focal wall thickening, and distinguish nonspecific filling defects such as enhancing tumor versus nonenhancing calculi or blood clots. Additionally, CTU and MRU can assess nonfunctioning/obstructed kidneys that would not excrete contrast medium required for excretory urography [5,37]. Based on these strengths, Jinzaki et al [37] concluded that CTU should be considered as the initial examination for the evaluation of patients at high risk for upper urinary tract UC, and Cohan et al [39] concluded that CTU can detect many more bladder cancers than excretory urography. FDG-PET/CT Skull Base to Mid-Thigh FDG-PET/CT is not ideal for evaluating the urinary collecting system due to FDG excretion in urine but can effectively assess nodal and metastatic disease. A study by Goodfellow et al [90] involving 233 patients found that CT had a sensitivity and specificity of 45% and 98%, respectively, in detecting pelvic lymph node metastases. FDG- Pretreatment Staging of Urothelial Cancer PET/CT increased sensitivity to 69%, with a slight reduction in specificity to 95%. In a prospective study of 25 patients by Nayak et al [91], FDG-PET/CT had a sensitivity of 78% compared with CT, with a sensitivity of 44% in detecting positive lymph nodes for metastases on histopathology. Other studies have reported the sensitivity of FDG-PET/CT for lymph node metastasis detection ranging from 47% to 56% and the specificity ranging from 93% to 98%, with specificity usually slightly lower than for CT [92]. Pichler et al [93] retrospectively analyzed 70 patients with bladder cancer staged with FDG-PET/CT before radical cystectomy and found that using an 8-mm cutoff, CT had a specificity of 92%, whereas FDG-PET alone had a sensitivity, specificity, and accuracy of 55%, 90%, and 84%, respectively.