US Kidneys and Bladder Retroperitoneal There is no relevant literature to support the use of US kidneys and bladder retroperitoneal in the evaluation of MIBC. US Pelvis (Bladder) Transabdominal grayscale US is not commonly used for staging bladder cancer because of its potential to overstage superficial tumors in 48% to 49% of cases and to underestimate invasive tumors in 5% to 11% of cases [35]. However, US can be a useful tool for evaluating hematuria. In a study of 1,007 patients with gross hematuria [65], US had a sensitivity of 63% and a specificity of 99% in detecting bladder cancer. Another study by Fang et al [66], which included 214 new cases of bladder cancer with pathological correlation, reported an overall accuracy of 79% in local staging using transabdominal US, with 10% overstaging and 12% understaging. It is important to note that transabdominal US is limited in visualizing beyond the bladder wall and cannot reliably detect nodal enlargement [112]. Furthermore, transabdominal US is less accurate in detecting stage T3 and T4 disease compared with T1 and T2 disease [64]. Three-dimensional US rendering is a new diagnostic tool that shows potential in discriminating NMIBC from MIBC [68]. It allows for retrieval and manipulation of volume data in multiple planes, increasing objectivity and improving primary bladder tumor diagnosis rate (100% with 3-D US versus 88.9% with 2-D US) when identifying T3b disease [69]. However, the technique has limitations, including difficulty in visualizing the entire tumor, particularly in flat or plaque-like tumors, presence of coexistent calcification, a rigid abdominal wall, or central obesity [70]. Contrast- enhanced US has also been shown to better differentiate MIBC from NMIBC [71]. In a study of 34 patients who underwent both grayscale and contrast-enhanced US before TURBT [71], contrast-enhanced US performance was
Pretreatment Staging of Urothelial Cancer. US Kidneys and Bladder Retroperitoneal There is no relevant literature to support the use of US kidneys and bladder retroperitoneal in the evaluation of MIBC. US Pelvis (Bladder) Transabdominal grayscale US is not commonly used for staging bladder cancer because of its potential to overstage superficial tumors in 48% to 49% of cases and to underestimate invasive tumors in 5% to 11% of cases [35]. However, US can be a useful tool for evaluating hematuria. In a study of 1,007 patients with gross hematuria [65], US had a sensitivity of 63% and a specificity of 99% in detecting bladder cancer. Another study by Fang et al [66], which included 214 new cases of bladder cancer with pathological correlation, reported an overall accuracy of 79% in local staging using transabdominal US, with 10% overstaging and 12% understaging. It is important to note that transabdominal US is limited in visualizing beyond the bladder wall and cannot reliably detect nodal enlargement [112]. Furthermore, transabdominal US is less accurate in detecting stage T3 and T4 disease compared with T1 and T2 disease [64]. Three-dimensional US rendering is a new diagnostic tool that shows potential in discriminating NMIBC from MIBC [68]. It allows for retrieval and manipulation of volume data in multiple planes, increasing objectivity and improving primary bladder tumor diagnosis rate (100% with 3-D US versus 88.9% with 2-D US) when identifying T3b disease [69]. However, the technique has limitations, including difficulty in visualizing the entire tumor, particularly in flat or plaque-like tumors, presence of coexistent calcification, a rigid abdominal wall, or central obesity [70]. Contrast- enhanced US has also been shown to better differentiate MIBC from NMIBC [71]. In a study of 34 patients who underwent both grayscale and contrast-enhanced US before TURBT [71], contrast-enhanced US performance was