Accurate non-invasive differentiation of primary liver cancers, such as hepatocellular carcinoma (HCC), intrahepatic cholangiocarcinoma (iCCA), and combined hepatocellular-cholangiocarcinoma (cHCC-CCA), is crucial for optimal management but challenging due to shared risk factors and overlapping imaging phenotypes. While the Liver Imaging Reporting and Data System category M effectively captures the classic targetoid appearance of large duct type iCCA, the small duct type frequently exhibits HCC-mimicking non-rim arterial phase hyperenhancement and non-peripheral washout, potentially compromising diagnostic specificity. Furthermore, cHCC-CCA presents a formidable diagnostic dilemma, existing on a continuous imaging spectrum that reflects its histologic dominance. This continuous imaging spectrum not only blurs radiologic distinctions but also complicates tissue sampling, limiting the diagnostic accuracy of core needle biopsies and highlighting the risk of misclassification. To enhance diagnostic clarity, this review highlights their key imaging hallmarks: while HCC typically shows non-rim arterial phase hyperenhancement (APHE) and non-peripheral washout, large duct iCCA displays a classic targetoid appearance with rim APHE and progressive central enhancement. Conversely, small duct iCCA often mimics HCC, and cHCC-CCA exhibits a variable spectrum depending on its predominant histologic component. Ultimately, overcoming these diagnostic pitfalls requires a rigorous, multidisciplinary approach that synthesizes imaging findings, serologic tumor markers, and clinical contexts.

Hepatic angiomyolipoma is a rare benign tumor that often mimics hepatocellular carcinoma on imaging. Here, we report a rare case of hepatic angiomyolipoma with extensive hemorrhagic degeneration, resulting in a large hemorrhagic component that mimicked a complicated cystic neoplasm. A 43-year-old woman presented with mild abdominal distension, and imaging revealed a 16-cm multiloculated cystic mass in the left hepatic lobe. Computed tomography revealed a thick, enhancing wall and septa with hyperattenuating internal fluid. On gadoxetic acid-enhanced magnetic resonance imaging, arterial enhancement was observed along the thick wall, and a subtle opposedphase signal drop indicated a small fat component that was initially missed. Laparoscopic left lobectomy was performed under suspicion of a malignant cystic neoplasm. Histopathological examination revealed an angiomyolipoma composed of thick-walled vessels, spindle-shaped muscle bundles, and scant adipocytes, with human melanoma black 45 positivity and absence of an epithelial lining, consistent with hemorrhagic degeneration. This case highlights how hemorrhagic degeneration can pose a significant diagnostic challenge by masking the typical features of hepatic angiomyolipoma, leading to diagnostic confusion with complicated cystic tumors.

Pneumocystis jirovecii pneumonia (PJP) is a life-threatening infection commonly observed in immunocompromised patients, necessitating prompt diagnosis and treatment. This review evaluates the diagnostic performance of various tests used for PJP diagnosis through a comprehensive literature review. Additionally, we propose a diagnostic algorithm tailored to non-human immunodeficiency virus immunocompromised patients, considering the specific characteristics of current medical resources in Korea.

Pneumocystis jirovecii pneumonia (PJP) is a life-threatening infection commonly observed in immunocompromised patients, necessitating prompt diagnosis and treatment. This review evaluates the diagnostic performance of various tests used for PJP diagnosis through a comprehensive literature review. Additionally, we propose a diagnostic algorithm tailored to non-human immunodeficiency virus immunocompromised patients, considering the specific characteristics of current medical resources in Korea.

Pneumocystis jirovecii pneumonia (PJP) is a life-threatening infection commonly observed in immunocompromised patients, necessitating prompt diagnosis and treatment. This review evaluates the diagnostic performance of various tests used for PJP diagnosis through a comprehensive literature review. Additionally, we propose a diagnostic algorithm tailored to non-human immunodeficiency virus immunocompromised patients, considering the specific characteristics of current medical resources in Korea.

Intrahepatic cholangiocarcinoma (iCCA) is a heterogeneous bile duct adenocarcinoma with a rising global incidence and a poor prognosis. This review aims to present a comprehensive overview of the most recent radiological research on iCCA, focusing on its histopathologic subclassification and the use of imaging findings to predict prognosis and inform treatment decisions. Histologically, iCCA is subclassified into small duct (SD-iCCA) and large duct (LD-iCCA) types. SD-iCCA typically arises in the peripheral small bile ducts and is often associated with chronic hepatitis or cirrhosis. It presents as a mass-forming lesion with a relatively favorable prognosis. LD-iCCA originates near the hepatic hilum, is linked to chronic bile duct diseases, and exhibits more aggressive behavior and poorer outcomes.Imaging is essential for differentiating these subtypes and assessing prognostic factors like tumor size, multiplicity, vascular invasion, lymph node metastasis, enhancement patterns, and intratumoral fibrosis. Imaging-based prognostic models have demonstrated predictive accuracy comparable to traditional pathological staging systems. Furthermore, imaging findings are instrumental in guiding treatment decisions, including those regarding surgical planning, lymphadenectomy, neoadjuvant therapy, and the selection of targeted therapies based on molecular profiling. Advancements in radiological research have improved our understanding of iCCA heterogeneity, facilitating prognosis prediction and treatment personalization. Imaging findings assist in subclassifying iCCA, predicting outcomes, and informing treatment decisions, thus optimizing patient management. Incorporating imaging-based approaches into clinical practice is crucial for advancing personalized medicine in the treatment of iCCA. However, further high-level evidence from international multicenter prospective studies is required to validate these findings and increase their clinical applicability.

Intrahepatic cholangiocarcinoma (iCCA) is a heterogeneous bile duct adenocarcinoma with a rising global incidence and a poor prognosis. This review aims to present a comprehensive overview of the most recent radiological research on iCCA, focusing on its histopathologic subclassification and the use of imaging findings to predict prognosis and inform treatment decisions. Histologically, iCCA is subclassified into small duct (SD-iCCA) and large duct (LD-iCCA) types. SD-iCCA typically arises in the peripheral small bile ducts and is often associated with chronic hepatitis or cirrhosis. It presents as a mass-forming lesion with a relatively favorable prognosis. LD-iCCA originates near the hepatic hilum, is linked to chronic bile duct diseases, and exhibits more aggressive behavior and poorer outcomes.Imaging is essential for differentiating these subtypes and assessing prognostic factors like tumor size, multiplicity, vascular invasion, lymph node metastasis, enhancement patterns, and intratumoral fibrosis. Imaging-based prognostic models have demonstrated predictive accuracy comparable to traditional pathological staging systems. Furthermore, imaging findings are instrumental in guiding treatment decisions, including those regarding surgical planning, lymphadenectomy, neoadjuvant therapy, and the selection of targeted therapies based on molecular profiling. Advancements in radiological research have improved our understanding of iCCA heterogeneity, facilitating prognosis prediction and treatment personalization. Imaging findings assist in subclassifying iCCA, predicting outcomes, and informing treatment decisions, thus optimizing patient management. Incorporating imaging-based approaches into clinical practice is crucial for advancing personalized medicine in the treatment of iCCA. However, further high-level evidence from international multicenter prospective studies is required to validate these findings and increase their clinical applicability.

Intrahepatic cholangiocarcinoma (iCCA) is a heterogeneous bile duct adenocarcinoma with a rising global incidence and a poor prognosis. This review aims to present a comprehensive overview of the most recent radiological research on iCCA, focusing on its histopathologic subclassification and the use of imaging findings to predict prognosis and inform treatment decisions. Histologically, iCCA is subclassified into small duct (SD-iCCA) and large duct (LD-iCCA) types. SD-iCCA typically arises in the peripheral small bile ducts and is often associated with chronic hepatitis or cirrhosis. It presents as a mass-forming lesion with a relatively favorable prognosis. LD-iCCA originates near the hepatic hilum, is linked to chronic bile duct diseases, and exhibits more aggressive behavior and poorer outcomes.Imaging is essential for differentiating these subtypes and assessing prognostic factors like tumor size, multiplicity, vascular invasion, lymph node metastasis, enhancement patterns, and intratumoral fibrosis. Imaging-based prognostic models have demonstrated predictive accuracy comparable to traditional pathological staging systems. Furthermore, imaging findings are instrumental in guiding treatment decisions, including those regarding surgical planning, lymphadenectomy, neoadjuvant therapy, and the selection of targeted therapies based on molecular profiling. Advancements in radiological research have improved our understanding of iCCA heterogeneity, facilitating prognosis prediction and treatment personalization. Imaging findings assist in subclassifying iCCA, predicting outcomes, and informing treatment decisions, thus optimizing patient management. Incorporating imaging-based approaches into clinical practice is crucial for advancing personalized medicine in the treatment of iCCA. However, further high-level evidence from international multicenter prospective studies is required to validate these findings and increase their clinical applicability.

Intrahepatic cholangiocarcinoma (iCCA) is a heterogeneous bile duct adenocarcinoma with a rising global incidence and a poor prognosis. This review aims to present a comprehensive overview of the most recent radiological research on iCCA, focusing on its histopathologic subclassification and the use of imaging findings to predict prognosis and inform treatment decisions. Histologically, iCCA is subclassified into small duct (SD-iCCA) and large duct (LD-iCCA) types. SD-iCCA typically arises in the peripheral small bile ducts and is often associated with chronic hepatitis or cirrhosis. It presents as a mass-forming lesion with a relatively favorable prognosis. LD-iCCA originates near the hepatic hilum, is linked to chronic bile duct diseases, and exhibits more aggressive behavior and poorer outcomes.Imaging is essential for differentiating these subtypes and assessing prognostic factors like tumor size, multiplicity, vascular invasion, lymph node metastasis, enhancement patterns, and intratumoral fibrosis. Imaging-based prognostic models have demonstrated predictive accuracy comparable to traditional pathological staging systems. Furthermore, imaging findings are instrumental in guiding treatment decisions, including those regarding surgical planning, lymphadenectomy, neoadjuvant therapy, and the selection of targeted therapies based on molecular profiling. Advancements in radiological research have improved our understanding of iCCA heterogeneity, facilitating prognosis prediction and treatment personalization. Imaging findings assist in subclassifying iCCA, predicting outcomes, and informing treatment decisions, thus optimizing patient management. Incorporating imaging-based approaches into clinical practice is crucial for advancing personalized medicine in the treatment of iCCA. However, further high-level evidence from international multicenter prospective studies is required to validate these findings and increase their clinical applicability.

Intrahepatic cholangiocarcinoma (iCCA) is a heterogeneous bile duct adenocarcinoma with a rising global incidence and a poor prognosis. This review aims to present a comprehensive overview of the most recent radiological research on iCCA, focusing on its histopathologic subclassification and the use of imaging findings to predict prognosis and inform treatment decisions. Histologically, iCCA is subclassified into small duct (SD-iCCA) and large duct (LD-iCCA) types. SD-iCCA typically arises in the peripheral small bile ducts and is often associated with chronic hepatitis or cirrhosis. It presents as a mass-forming lesion with a relatively favorable prognosis. LD-iCCA originates near the hepatic hilum, is linked to chronic bile duct diseases, and exhibits more aggressive behavior and poorer outcomes.Imaging is essential for differentiating these subtypes and assessing prognostic factors like tumor size, multiplicity, vascular invasion, lymph node metastasis, enhancement patterns, and intratumoral fibrosis. Imaging-based prognostic models have demonstrated predictive accuracy comparable to traditional pathological staging systems. Furthermore, imaging findings are instrumental in guiding treatment decisions, including those regarding surgical planning, lymphadenectomy, neoadjuvant therapy, and the selection of targeted therapies based on molecular profiling. Advancements in radiological research have improved our understanding of iCCA heterogeneity, facilitating prognosis prediction and treatment personalization. Imaging findings assist in subclassifying iCCA, predicting outcomes, and informing treatment decisions, thus optimizing patient management. Incorporating imaging-based approaches into clinical practice is crucial for advancing personalized medicine in the treatment of iCCA. However, further high-level evidence from international multicenter prospective studies is required to validate these findings and increase their clinical applicability.