Multidetector row CT of the liver

CT has always played a major role in the imaging of the liver despite continuous challenge by ultrasound and MR imaging. Introduction of multidetector row CT technology has helped CT to excel in its already established indications and has expanded its capabilities by adding new clinical indications, such as CT angiography or liver perfusion. This article discusses the advantages of multidetector row CT scanners in liver imaging, examines the guidelines to improve image quality by optimizing scanning protocols and contrast administration strategies, and reviews the current and potential clinical applications.     

Extrahepatic Bile Duct Adenocarcinoma: Patients at High-Risk for Local Recurrence Treated with Surgery and Adjuvant Chemoradiation Have an Equivalent Overall Survival to Patients with Standard-Risk Treated with Surgery Alone

Background  Patients with resected extrahepatic bile duct adenocarcinoma who have microscopically positive resection margins and/or pathologic locoregional nodal involvement (R1pN1) have a high-risk of locoregional recurrence, and therefore, we advocate the use of adjuvant chemoradiation. To evaluate the safety and effectiveness of this treatment, we compared survival and side effects outcomes between such patients and patients with negative resection margins and pathologically negative nodes (R0pN0) who did not receive adjuvant treatment. Methods  Between 1984 and 2005, 65 patients were treated with curative-intended resection for extrahepatic bile duct adenocarcinoma. Patients with tumors arising in the gallbladder and periampullary region were excluded. Pathology and diagnostic images were centrally reviewed. Overall survival and locoregional recurrence outcomes for patients with standard-risk R0pN0 (surgery alone, or S group, n = 23) were compared with those of patients with high locoregional recurrence risk, R1 and/or pN1 (R1pN1) status who received adjuvant chemoradiation (S-CRT group, n = 42). Results  The median follow-up for the entire group was 31 months. Patients in the S-CRT and S groups had a similar 5-year overall survival (36% vs. 42%, P = .6) and locoregional recurrence (5-year rate: 38% vs. 37%, P = .13). In the S-CRT group, three patients (7%) experienced an acute (grade 3 or more) side effect. Conclusions  Our finding of a lack of a survival difference between the S and S-CRT groups suggests that for patients with extrahepatic bile duct adenocarcinoma at high risk for locoregional recurrence (i.e., R1 resection or pN1 disease), adjuvant chemoradiation provides an equivalent overall survival despite of these worse prognostic features.     

TNM/Okuda/Barcelona/UNOS/CLIP International Multidisciplinary Classification of Hepatocellular Carcinoma: concepts,perspectives, and radiologic implications

Hepatocellular carcinoma (HCC) is a major health problem worldwide. Moreover, the liver cancer field is evolving rapidly, with early diagnosis, new therapies, and a better understanding of HCC’s biology and development. Accurate staging is important for determining prognosis and selecting the most appropriate treatment for each patient. Surgical intervention remains the most effective treatment for HCC and is the only potentially curative modality. However, in HCC patients, overall survival is also independently affected by underlying liver disease and cirrhosis, which in turn affect the applicability and efficacy of treatment. Although several staging classification and prognostic scoring systems have been proposed for determining the stage and prognosis of HCC, no consensus exists on the best classification method. The most common staging classification systems include tumor-node-metastasis stage, Okuda staging, Cancer of the Liver Italian Program score, Barcelona Clinic Liver Cancer staging classification, the French, the Chinese University Prognostic Index, Japanese Integrated Scoring, and the Tokyo score. Radiologists should be aware of the different staging classification systems for HCC and familiar with the system relevant to their respective referring clinicians, as it will provide pertinent radiological evaluation for multidisciplinary management.     

Update on 3D and multiplanar MDCT in the assessment of biliary and pancreatic pathology

The development of multidetector row computed tomography (MDCT) has led to the acquisition of true isotropic voxels that can be postprocessed to yield images in any plane of the same resolution as the original axially acquired images. This, coupled with rapid MDCT imaging during peak target organ enhancement has led to a variety of means to review imaging information beyond that of the axial perspective. Postprocessing can be utilized to identify variant biliary anatomy to guide preoperative planning of biliary-related surgery, determine the level and cause of biliary obstruction and assist in staging of biliary cancer. Postprocessing can also be used to identify pancreatic ductal variants, visualize diagnostic features of pancreatic cystic lesions, diagnose and stage pancreatic cancer, and differentiate pancreatic from peripancreatic disease.     

Learning the nodal stations in the abdomen

The normal pathways of lymphatic drainage from the abdominal organs have been well described in the classic anatomy literature. Knowledge of the location and nomenclature of the common nodal stations in the abdomen are essential for complete report of radiological findings. CT is ubiquitous in the evaluation of oncology patients. Utilizing colour-coded CT images of the abdomen we will present the nomenclature and location of the nodal stations for common abdominal neoplasms, including those of the stomach, pancreas, liver, colon and the kidney. Understanding the nomenclature and the usual lymphatic pathways of metastasis will help radiologists detect disease spread from abdominal tumours. The goal of this pictorial review is to present the nodal stations, nomenclature and location of regional lymph nodes for the most common abdominal neoplasms. In addition, the reader can use this document as a handbook to learn and review this information.