MRU There is no relevant literature suggesting that MRU offers any additional benefit over conventional MRI of the abdomen in the initial staging of RCC, and thus, this method is not included in the guidelines from the EAU and NCCN [5,13]. Radiography Chest The lung is the most common site of metastases in patients with RCC presenting with synchronous metastases. Although the incidence of metastases in RCC <4 cm is low (approximately 1%-2%), it has been reported that 20% to 30% of T1a tumors may have potentially aggressive histologic features. Hence, chest radiography is usually performed in the staging of RCC [13]. However, CT is more sensitive than radiography for the detection of pulmonary metastases from RCC during staging. In addition to a high sensitivity for the detection of pulmonary metastases, chest CT has a high sensitivity for the detection of intrathoracic nodal metastases from RCC. Therefore, in patients with higher risk of pulmonary metastases (such as tumor >4 cm, cN1, presence of systemic symptoms), chest CT is preferred [54,55]. US Abdomen US can be useful in the characterization of renal masses as it can help in differentiating solid and cystic renal masses. However, it is seldom used in the staging of RCC because of its relatively poor performance in evaluating local tumor spread and metastatic disease [70,71]. Additional challenges in the use of US may be related to incomplete visualization of the mass, acoustic shadowing from partially calcified cysts or masses, variability in echogenicity of hemorrhagic cysts, and poor sensitivity in diagnosing isoechoic small renal tumors. There is no relevant literature suggesting that US offers any additional benefit over conventional CT or MRI of the abdomen in the initial staging of RCC, and thus, this method is not included in the guidelines [5,13]. However, intraoperative US may be helpful in performing partial nephrectomy, especially in patients with endophytic renal tumors [72,73]. Variant 3: Renal cell carcinoma.
Staging of Renal Cell Carcinoma. MRU There is no relevant literature suggesting that MRU offers any additional benefit over conventional MRI of the abdomen in the initial staging of RCC, and thus, this method is not included in the guidelines from the EAU and NCCN [5,13]. Radiography Chest The lung is the most common site of metastases in patients with RCC presenting with synchronous metastases. Although the incidence of metastases in RCC <4 cm is low (approximately 1%-2%), it has been reported that 20% to 30% of T1a tumors may have potentially aggressive histologic features. Hence, chest radiography is usually performed in the staging of RCC [13]. However, CT is more sensitive than radiography for the detection of pulmonary metastases from RCC during staging. In addition to a high sensitivity for the detection of pulmonary metastases, chest CT has a high sensitivity for the detection of intrathoracic nodal metastases from RCC. Therefore, in patients with higher risk of pulmonary metastases (such as tumor >4 cm, cN1, presence of systemic symptoms), chest CT is preferred [54,55]. US Abdomen US can be useful in the characterization of renal masses as it can help in differentiating solid and cystic renal masses. However, it is seldom used in the staging of RCC because of its relatively poor performance in evaluating local tumor spread and metastatic disease [70,71]. Additional challenges in the use of US may be related to incomplete visualization of the mass, acoustic shadowing from partially calcified cysts or masses, variability in echogenicity of hemorrhagic cysts, and poor sensitivity in diagnosing isoechoic small renal tumors. There is no relevant literature suggesting that US offers any additional benefit over conventional CT or MRI of the abdomen in the initial staging of RCC, and thus, this method is not included in the guidelines [5,13]. However, intraoperative US may be helpful in performing partial nephrectomy, especially in patients with endophytic renal tumors [72,73]. Variant 3: Renal cell carcinoma.