Clinical Staging of Mass‐Forming Intrahepatic Cholangiocarcinoma: Computed Tomography Versus Magnetic Resonance Imaging

Abstract

We compared the performance of computed tomography (CT) and magnetic resonance imaging (MRI) for preoperative clinical staging of mass-forming intrahepatic cholangiocarcinoma (iCCA), using the eighth American Joint Committee on Cancer (AJCC) system. This retrospective, multicenter, cohort study consecutively identified patients who underwent partial hepatectomy for mass-forming iCCA and had preoperative CT and MRI performed from January 2009 to December 2015. CT and MRI characteristics were used to determine clinical stage based on the eighth AJCC system. Performances of CT and MRI for clinical T and N staging were compared using generalized estimating equations. In 334 patients (median age, 63 years; 221 men), MRI sensitivities were significantly higher than CT sensitivities for detecting T1b or higher stages (91.0% vs. 80.5%, respectively, P < 0.001), T2 or higher stages (89.1% vs. 73.8%, respectively, P < 0.001), and T3 or T4 stage (77.8% vs. 58.0%, respectively, P < 0.001). MRI was also more sensitive at identifying multiple tumors than CT (66.7% vs. 50.0%, respectively, P = 0.026), without a significant difference in specificity (78.1% vs. 80.1%, respectively, P = 0.342). Sensitivities were comparable between CT and MRI for determination of size >5 cm (i.e., T1b for single tumor) and extrahepatic organ invasion (i.e., T4). Sensitivities of CT and MRI were not different for N stage (65.0% vs. 64.0%, respectively, P = 0.808), but the specificity of CT was significantly higher than that of MRI (80.7% vs. 72.9%, respectively, P = 0.001) when using a composite reference standard. Conclusion: MRI showed superior sensitivity to CT for diagnosing T2 and T3 stages, particularly multiple tumors. CT and MRI had comparable sensitivity for N staging, but CT provided higher specificity than MRI. (Hepatology Communications 2021;0:1-10). I ntrahepatic cholangiocarcinoma (iCCA) is the second most common primary liver cancer, accounting for approximately 15% of primary liver cancers. (1,2) The incidence of iCCA is highest in Eastern countries, such as Thailand, South Korea, and China, but its incidence and mortality are increasing worldwide. (1)(2)(3) iCCA arises from canals of Hering to second-order bile ducts and is differentiated from perihilar or distal cholangiocarcinoma by anatomic location. iCCA most commonly presents as

Multiparametric Magnetic Resonance Imaging Improves the Prognostic Outcomes in Patients With Intrahepatic Cholangiocarcinoma After Curative-Intent Resection

“…As part of the AJCC/UICC staging system, tumor size and number are two indispensable prognostic factors in patients with ICC ( 24 ). In our study, more nodules were detected using mpMRI, which was in accordance with previous studies that MRI enabled to detect more additional focal liver lesions than CT ( 18 , 25 ). This may be due to the superior high soft tissue resolution of MR imaging.…”

“…Diffusion-weighted imaging (DWI), characterized by quantitative measurement of water diffusion in tissues, is important for evaluating tumor margins and detecting intrahepatic metastasis and lymph node metastasis (16). Moreover, dynamic contrast MRI is superior to CECT for the detection of small liver lesions, and it theoretically evaluates angioinvasion due to superior data acquisition and inherently greater contrast resolution (17)(18)(19). Based on the advantage of multiparametric imaging with MRI (mpMRI), it is helpful to detect bile duct invasion and occult intrahepatic metastasis and guide surgeons in making comprehensive surgical plans.…”

Integrative Analysis of Intrahepatic Cholangiocarcinoma Subtypes for Improved Patient Stratification: Clinical, Pathological, and Radiological Considerations

“…Various radiologic approaches have been proposed to distinguish iCCA subtypes. However, subtype comparisons are complicated by the fact that some even recently published studies only distinguish between mass-forming iCCAs and non-massforming iCCAs without considering the final histopathological subtype [14][15][16][17]. In general, large duct iCCAs more often shows a ductal accentuated growth pattern with consecutive biliary obstruction [18].…”

“…CT is considered the standard imaging method for the assessment of liver masses, but is only of limited use for determining the exact tumor extent along bile ducts, and hence, the resectability [36]. Due to the high spatial resolution of CT and the better representation of soft tissues, in iCCAs, MRI is more sensitive but less specific than CT [15]. Overall, however, our approach primarily reflects clinical reality.…”

Treatment of Intrahepatic Cholangiocarcinoma—A Multidisciplinary Approach

“…In this case, either disease-related symptoms or cross-sectional imaging performed for other reasons lead to the diagnosis. The highest sensitivity for staging is provided by MRI, which outperforms computed tomography (CT) in terms of tumor stage and detection of multiple lesions in the liver [ 18 ]. Of note, the use of portal venous phase washout instead of conventional washout in gadoxetic acid-enhanced MR imaging prevents misdiagnosis of iCC as HCC in liver cirrhosis [ 19 ].…”