Role of three-dimensional imaging in operative planning for hilar cholangiocarcinoma

Analysis of the caudate artery with three-dimensional imaging

BACKGROUND/PURPOSE

To date there have been only a few radiological studies of the caudate artery. This study aimed to precisely analyze the caudate artery as well as the relationship between the caudate arteries, the arterial plexus at the hilar plate, and the hilar bile duct.

METHODS

Reconstructed three-dimensional (3D) computed tomography images from 50 patients during hepatic arteriography were analyzed. The caudate arteries were classified as right branches (Irs) or left branches (Ils). The communicating artery (CA) was defined as the artery connecting the right, left, segmental, and common hepatic arteries.

RESULTS

The caudate artery was divided into 3 types: an independent branch (Type 1); the common tract formed by Ir and Il (Type 2); and an arterial branch from the CA (Type 3). The CA was recognized in 25 of 50 patients. There was a total of 65 arteries to the hilar bile duct observed in 40 patients, and 24 (37 %) of these 65 arteries to the hilar bile duct originated from the caudate artery or CA.

CONCLUSION

The caudate artery plays an important role not only in connecting the blood supply of the right and left livers but in the blood supply to the hilar bile duct.

Left hepatic trisectionectomy for advanced perihilar cholangiocarcinoma

BACKGROUND

Data on outcomes of left hepatic trisectionectomy (LT) for perihilar cholangiocarcinoma are limited. The aim of this study was to clarify short- and long-term outcomes of LT for perihilar cholangiocarcinoma.

METHODS

Patients with perihilar cholangiocarcinoma who underwent LT between January 2000 and October 2011 were analysed. Surgical variables, mortality, morbidity (Clavien grade I-V), recurrence sites and survival were compared between subjects who underwent LT, right hemihepatectomy or left hemihepatectomy.

RESULTS

A total 214 patients underwent resection for perihilar cholangiocarcinoma, 25 (11·7 per cent) of whom underwent LT, 88 (41·1 per cent) right hemihepatectomy and 94 (43·9 per cent) left hepatectomy. There were no deaths among those who had LT, but 20 patients developed complications. The incidence of grade IIIa complications was significantly higher among patients who underwent LT than in patients who had right or left hemihepatectomy (P = 0·001 and P < 0·001 respectively). Only one patient developed a grade IIIb or IV complication (liver failure) after LT. The overall 5-year survival rate after LT was 39 per cent and median survival was 45 months. There were no significant differences in survival between patients who underwent LT and those who had a right or left hemihepatectomy.

CONCLUSION

LT may provide a good outcome for advanced perihilar cholangiocarcinoma.

Development of a novel fusion imaging technique in the diagnosis of hepatobiliary-pancreatic lesions

INTRODUCTION

Multi-row detector computed tomography (MDCT) and magnetic resonance cholangiopancreatography (MRCP) play an important role in the imaging diagnosis of hepatobiliary-pancreatic lesions. Here we investigated whether unifying the MDCT and MRCP images onto the same screen using fusion imaging could overcome the limitations of each technique, while still maintaining their benefits. Moreover, because reports of fusion imaging using MDCT and MRCP are rare, we assessed the benefits and limitations of this method for its potential application in a clinical setting.

METHODS

The patient group included 9 men and 11 women. Among the 20 patients, the final diagnoses were as follows: 10 intraductal papillary mucinous neoplasms, 5 biliary system carcinomas, 1 pancreatic adenocarcinoma and 5 non-neoplastic lesions. After transmitting the Digital Imaging and Communication in Medicine data of the MDCT and MRCP images to a workstation, we performed a 3-D organisation of both sets of images using volume rendering for the image fusion.

RESULTS

Fusion imaging enabled clear identification of the spatial relationship between a hepatobiliary-pancreatic lesion and the solid viscera and/or vessels. Further, this method facilitated the determination of the relationship between the anatomical position of the lesion and its surroundings more easily than either MDCT or MRCP alone.

CONCLUSION

Fusion imaging is an easy technique to perform and may be a useful tool for planning treatment strategies and for examining pathological changes in hepatobiliary-pancreatic lesions. Additionally, the ease of obtaining the 3-D images suggests the possibility of using these images to plan intervention strategies.

Radiological staging in patients with hilar cholangiocarcinoma: a systematic review and meta-analysis

OBJECTIVE

To obtain diagnostic performance values of CT, MRI, ultrasound and 18-fludeoxyglucose positron emission tomography (PET)/CT for staging of hilar cholangiocarcinoma.

METHODS

A comprehensive systematic search was performed for articles published up to March 2011 that fulfilled the inclusion criteria. Study quality was assessed with the quality assessment of diagnostic accuracy studies tool.

RESULTS

16 articles (448 patients) were included that evaluated CT (n=11), MRI (n=3), ultrasound (n=3), or PET/CT (n=1). Overall, their quality was moderate. The accuracy estimates for evaluation of CT for ductal extent of the tumour was 86%. The sensitivity and specificity estimates of CT were 89% and 92% for evaluation of portal vein involvement, 83% and 93% for hepatic artery involvement, and 61% and 88% for lymph node involvement, respectively. Data were too limited for adequate comparisons of the different techniques.

CONCLUSION

Diagnostic accuracy studies of CT, MRI, ultrasound or PET/CT for staging of hilar cholangiocarcinoma are sparse and have moderate methodological quality. Data primarily concern CT, which has an acceptable accuracy for assessment of ductal extent, portal vein and hepatic artery involvement, but low sensitivity for nodal status.

Diagnostic ability of MDCT to assess right hepatic artery invasion by perihilar cholangiocarcinoma with left-sided predominance

BACKGROUND/PURPOSE

There have been few reports on the diagnostic ability of multidetector-row computed tomography (MDCT) to assess invasion of the hepatic artery. The aim of this study was to assess the diagnostic ability of MDCT for right hepatic artery (RHA) invasion.

METHODS

From August 2006 to October 2010, 103 consecutive patients with left-sided predominance perihilar cholangiocarcinoma underwent left-sided hepatectomy; all patients received MDCT as a preoperative workup. Three-dimensional volume-rendered and multiplanar reformation (MPR) images were retrospectively examined for evidence of RHA invasion, and the agreement between intraoperative macroscopic and histologic findings was assessed.

RESULTS

No macroscopic evidence of RHA invasion was found in any of the 50 patients presenting visible low-density planes on MPR images between the RHA and adjacent tumor. Of the remaining 53 patients without visible low-density planes, 38 patients presented macroscopic evidence of RHA invasion and underwent combined RHA resection; the other 15 patients did not exhibit RHA invasion. The RHA contact length, as measured on MDCT images by curved planar reformations, was significantly longer in the former 38 patients than in the latter 15 patients (24.3 ± 16.9 vs. 8.6 ± 3.0 mm, respectively, P = 0.001). Histologic cancer infiltration of the resected RHA was found in 18 (47.4%) of the 38 patients who underwent RHA resection. Diagnosis of macroscopic RHA invasion based on the presence or absence of a low-density plane had an accuracy of 85.4%.

CONCLUSIONS

We conclude that MDCT is useful for assessing RHA invasion by perihilar cholangiocarcinoma.

CT and MR cholangiography: advantages and pitfalls in perioperative evaluation of biliary tree

Recent developments in imaging technology have enabled CT and MR cholangiopancreatography (MRCP) to provide minimally invasive alternatives to endoscopic retrograde cholangiopancreatography for the pre- and post-operative assessment of biliary disease. This article describes anatomical variants of the biliary tree with surgical significance, followed by comparison of CT and MR cholangiographies. Drip infusion cholangiography with CT (DIC-CT) enables high-resolution three-dimensional anatomical representation of very small bile ducts (e.g. aberrant branches, the caudate branch and the cystic duct), which are potential causes of surgical complications. The disadvantages of DIC-CT include the possibility of adverse reactions to biliary contrast media and insufficient depiction of bile ducts caused by liver dysfunction or obstructive jaundice. Conventional MRCP is a standard, non-invasive method for evaluating the biliary tree. MRCP provides useful information, especially regarding the extrahepatic bile ducts and dilated intrahepatic bile ducts. Gadolinium ethoxybenzyl diethylenetriamine pentaacetic acid-enhanced MRCP may facilitate the evaluation of biliary structure and excretory function. Understanding the characteristics of each type of cholangiography is important to ensure sufficient perioperative evaluation of the biliary system.

The impact of portal vein resection on outcomes for hilar cholangiocarcinoma: a multi-institutional analysis of 305 cases

BACKGROUND. Surgical strategy for hilar cholangiocarcinoma often includes hepatectomy, but the role of portal vein resection (PVR) remains controversial. In this study, the authors sought to identify factors associated with outcome after surgical management of hilar cholangiocarcinoma and examined the impact of PVR on survival.

METHODS

Three hundred five patients who underwent curative-intent surgery for hilar cholangiocarcinoma between 1984 and 2010 were identified from an international, multi-institutional database. Clinicopathologic data were evaluated using univariate and multivariate analyses.

RESULTS

Most patients had hilar cholangiocarcinoma with tumors classified as T3/T4 (51.1%) and Bismuth-Corlette type II/III (60.9%). Resection involved extrahepatic bile duct resection (EHBR) alone (26.6%); or hepatectomy and EHBR without PVR (56.7%); or combined hepatectomy, EHBR, and PVR (16.7%). Negative resection (R0) margin status was higher among the patients who underwent hepatectomy plus EHBR (without PVR, 64.2%; with PVR, 66.7%) versus EHBR alone (54.3%; P < .001). The median number of lymph nodes assessed was higher among the patients who underwent hepatectomy plus EHBR (without PVR, 6 lymph nodes; with PVR, 4 lymph nodes) versus EHBR alone (2 lymph nodes; P < .001). The 90-day mortality rate was lower for patients who underwent EHBR alone (1.2%) compared with the rate for patients who underwent hepatectomy plus EHBR (without PVR, 10.6%, with PVR, 17.6%; P < .001). The overall 5-year survival rate was 20.2%. Factors that were associated with an adverse prognosis included lymph node metastasis (hazard ratio [HR], 1.79; P = .002) and R1 margin status (HR, 1.81; P < .001). Microscopic vascular invasion did not influence survival (HR, 1.23; P = .19). Among the patients who underwent hepatectomy plus EHBR, PVR was not associated with a worse long-term outcome (P = .76).

CONCLUSIONS

EHBR alone was associated with a greater risk of positive surgical margins and worse lymph node clearance. The current results indicated that hepatectomy should be considered the standard treatment for hilar cholangiocarcinoma, and PVR should be undertaken when necessary to extirpate all disease. Combined hepatectomy, EHBR, and PVR can offer long-term survival in some patients with advanced hilar cholangiocarcinoma.

Application of multi-slice spiral CT three-dimensional reconstruction technique in liver resection for hepatic carcinoma

Hepatic carcinoma is a very common disease across the world, and hepatic resection is still the best treatment. As the liver has complex anatomy and frequent vascular variations, it is of great importance to obtain some preoperative data, such as the position of liver cancer and its relationship with liver vessels and adjacent structures. Now, three-dimensional reconstruction technique allows to clearly show the relationship of the hepatic artery, portal vein, hepatic vein and tumor with surrounding strctures and accurately calculate the remnant liver volume, providing valuable preoperative imaging data for liver resection. This article will give an overview of three-dimensional reconstruction technique and discuss its ability to display liver vascularity, show the relationship between tumors and liver blood vessels, and predict liver resection volume.

Impact of three-dimensional analysis of multidetector row computed tomography cholangioportography in operative planning for hilar cholangiocarcinoma

BACKGROUND

A detailed evaluation of portal triad structures, especially the biliary anatomy at the hepatic hilus, is essential to ensure curative resection for hilar cholangiocarcinoma.

METHODS

Patients underwent 3-dimensional analysis using multidetector row computed tomography cholangioportography preoperatively. The number of bile duct orifices in the cut end of the hilar plate was estimated and compared with the actual number of bile ducts. Furthermore, the estimated length of the surgical margin and its relationship to the pathological margin status was evaluated.

RESULTS

The number of bile duct orifices was correctly estimated in 14 of 19 patients. Of 18 hepatic ducts in which the estimated length of the hepatic side surgical margin was calculated 17 hepatic ducts (94.4%) were diagnosed pathologically as margin negative.

CONCLUSIONS

This investigatory technique has the advantages of precise visualization of anatomic structures and multidirectional assessment of biliary branches and vessels, allowing improved operative planning for the treatment of hilar cholangiocarcinoma.

In vivo validation of a therapy planning system for laser-induced thermotherapy (LITT) of liver malignancies

PURPOSE

In situ ablation is increasingly being used for the treatment of liver malignancies. The application of these techniques is limited by the lack of a precise prediction of the destruction volume. This holds especially true in anatomically difficult situations, such as metastases in the vicinity of larger liver vessels. We developed a three-dimensional (3D) planning system for laser-induced thermotherapy (LITT) of liver tumors. The aim of the study was to validate the system for calculation of the destruction volume.

METHODS

LITT (28 W, 20 min) was performed in close contact to major hepatic vessels in six pigs. After explantation of the liver, the coagulation area was documented. The liver and its vascular structures were segmented from a pre-interventional CT scan. Therapy planning was carried out including the cooling effect of adjacent liver vessels. The lesions in vivo and the simulated lesions were compared with a morphometric analysis.

RESULTS

The volume of lesions in vivo was 6,568.3 ± 3,245.9 mm(3), which was not different to the simulation result of 6,935.2 ± 2,538.5 mm(3) (P = 0.937). The morphometric analysis showed a sensitivity of the system of 0.896 ± 0.093 (correct prediction of destructed tissue). The specificity was 0.858 ± 0.090 (correct prediction of vital tissue).

CONCLUSIONS

A 3D computer planning system for the prediction of thermal lesions in LITT was developed. The calculation of the directional cooling effect of intrahepatic vessels is possible for the first time. The morphometric analysis showed a good correlation under clinical conditions. The pre-therapeutic calculation of the ablation zone might be a valuable tool for procedure planning.

Endoscopic diagnosis of extrahepatic bile duct carcinoma: Advances and current limitations

The accurate diagnosis of extrahepatic bile duct carcinoma is difficult, even now. When ultrasonography (US) shows dilatation of the bile duct, magnetic resonance cholangiopancreatography followed by endoscopic US (EUS) is the next step. When US or EUS shows localized bile duct wall thickening, endoscopic retrograde cholangiopancreatography should be conducted with intraductal US (IDUS) and forceps biopsy. Fluorescence in situ hybridization increases the sensitivity of brush cytology with similar specificity. In patients with papillary type bile duct carcinoma, three biopsies are sufficient. In patients with nodular or infiltrating-type bile duct carcinoma, multiple biopsies are warranted, and IDUS can compensate for the limitations of biopsies. In preoperative staging, the combination of dynamic multi-detector low computed tomography (MDCT) and IDUS is useful for evaluating vascular invasion and cancer depth infiltration. However, assessment of lymph nodes metastases is difficult. In resectable cases, assessment of longitudinal cancer spread is important. The combination of IDUS and MDCT is useful for revealing submucosal cancer extension, which is common in hilar cholangiocarcinoma. To estimate the mucosal extension, which is common in extrahepatic bile duct carcinoma, the combination of IDUS and cholangioscopy is required. The utility of current peroral cholangioscopy is limited by the maneuverability of the “baby scope”. A new baby scope (10 Fr), called “SpyGlass” has potential, if the image quality can be improved. Since extrahepatic bile duct carcinoma is common in the Far East, many researchers in Japan and Korea contributed these studies, especially, in the evaluation of longitudinal cancer extension.

Surgical strategy for bile duct cancer: Advances and current limitations

The aim of this review is to describe recent advances and topics in the surgical management of bile duct cancer. Radical resection with a microscopically negative margin (R0) is the only way to cure cholangiocarcinoma and is associated with marked survival advantages compared to margin-positive resections. Complete resection of the tumor is the surgeon’s ultimate aim, and several advances in the surgical treatment for bile duct cancer have been made within the last two decades. Multidetector row computed tomography has emerged as an indispensable diagnostic modality for the precise preoperative evaluation of bile duct cancer, in terms of both longitudinal and vertical tumor invasion. Many meticulous operative procedures have been established, especially extended hepatectomy for hilar cholangiocarcinoma, to achieve a negative resection margin, which is the only prognostic factor under the control of the surgeon. A complete caudate lobectomy and resection of the inferior part of Couinaud’s segment IV coupled with right or left hemihepatectomy has become the standard surgical procedure for hilar cholangiocarcinoma, and pylorus-preserving pancreaticoduodenectomy is the first choice for distal bile duct cancer. Limited resection for middle bile duct cancer is indicated for only strictly selected cases. Preoperative treatments including biliary drainage and portal vein embolization are also indicated for only selected patients, especially jaundiced patients anticipating major hepatectomy. Liver transplantation seems ideal for complete resection of bile duct cancer, but the high recurrence rate and decreased patient survival after liver transplant preclude it from being considered standard treatment. Adjuvant chemotherapy and radiotherapy have a potentially crucial role in prolonging survival and controlling local recurrence, but no definite regimen has been established to date. Further evidence is needed to fully define the role of liver transplantation and adjuvant chemo-radiotherapy.

Liver tissue sparing resection using a novel planning tool

PURPOSE

Accurate preoperative prediction of liver function, volume, and vessel anatomy is essential in preventing postoperative liver failure, optimizing safety, and ensuring optimal outcome in patients undergoing hepatic surgery. We propose that preoperative resection planning provides useful anatomical and volumetric data, allowing for sparing of liver tissue in surgical resections. The purpose of the present study was to evaluate the use of a novel resection planning tool.

METHODS

Thirteen patients undergoing hemihepatectomy were included. Preoperative resection planning was performed using the commercially available software Mint Liver. During resection planning, virtual resections were calculated based on Couinaud classification, Cantlie's line (standard), and individually by the operating surgeon (individual). Intraoperatively, volume and weight of the resected specimen were measured. A 14-day follow-up was conducted, and laboratory parameters were collected. Statistical analysis was performed, comparing virtual resection volumes (i.e., standard vs. individual) and secondarily virtual vs. actual resection volume.

RESULTS

We found a significant difference (p = 0.001) in the comparison of standard vs. individual in all 13 cases, with an average 92.8 mL smaller resected volume, sparing 11.3% of liver parenchyma with virtual resection. No patients suffered from acute liver failure. Perioperative mortality was 0%.

CONCLUSION

Mint Liver is capable of acquiring exact anatomical and volumetric knowledge prior to hepatic resections. Liver parenchyma can be spared by preoperative assessment of the resection plan. We propose that this tool could be an important addition to preoperative patient evaluation, especially in complex liver surgery and living donor liver transplantation where precise volumetry is the decisive factor.

Gadobutrol-enhanced, three-dimensional, dynamic MR imaging with MR cholangiography for the preoperative evaluation of bile duct cancer

PURPOSE

To evaluate the diagnostic performance of 1.0-M gadobutrol-enhanced, 3-dimensional (3D), dynamic MR images with 3D-MR cholangiography (MRC) in the preoperative evaluation of bile duct cancer staging and resectability.

MATERIALS AND METHODS

Our institutional review board approved this retrospective study. Sixty patients (46 male, 14 female; mean age 65.9 years; range, 45-77 years) with surgically and pathologically proven bile duct cancers, were included in this study. Two gastrointestinal radiologists evaluated the biliary MR images, including 3D-MRC and gadobutrol-enhanced, dynamic images, using a 3D-gradient echo (GRE) technique, regarding the longitudinal tumor extent, vascular involvement of the bile duct cancer, lymph node metastasis, and tumor resectability. The results were compared with the surgical and pathology findings used as the reference standards.

RESULTS

The area under the receiver operating characteristic curve (Az) of the 2 reviewers was 0.95 and 0.93, respectively, for evaluation of the involvement of both secondary biliary confluences and 0.85 and 0.84, respectively, for assessment of the intrapancreatic duct. For determining the tumor resectability, the overall accuracy was 0.93 and 0.88, respectively, whereas for assessment of the vascular involvement, the Az values were 0.92 for reviewer 1 and 0.70 for reviewer 2 for the portal vein evaluation, and 0.99 for reviewer 1 and 0.76 for reviewer 2 for the hepatic artery evaluation. In the assessment of lymph node metastasis, the overall accuracy was approximately 0.77 for each reviewer.

CONCLUSION

One-molar, gadobutrol-enhanced, dynamic imaging, using a 3D-GRE technique with isotropic 3D-MRC showed excellent diagnostic capability for assessing the longitudinal extent and tumor resectability of bile duct cancer, although it generally underestimated the tumor involvement of vessels and lymph nodes.

Diagnostic accuracy of multidetector-row computed tomography for hilar cholangiocarcinoma

BACKGROUND AND AIM

The aim of this study was to investigate the diagnostic reliability of multidetector-row computed tomography (MDCT) for the evaluation of tumor spread in hilar cholangiocarcinoma.

METHODS

Images obtained from a 16-detector row scanner of 22 patients were interpreted. The diagnostic accuracy of longitudinal ductal spread, vertical invasion (including hepatic parenchyma), and lymph node metastasis was assessed with reference to histopathological findings.

RESULTS

The location of the tumor was correctly diagnosed in 95% of cases (21/22), but in five of these cases, the cut end of the intrahepatic bile duct was positive, resulting in 77% diagnostic accuracy for longitudinal spread. Among the patients with a negative bile duct surgical margin, there was a significant difference in the measurement of tumor spread between MDCT and microscopic investigation (P < 0.001). For vertical invasion, the sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) of MDCT were 69%, 100%, 100%, and 69% for the liver parenchyma, respectively. The sensitivity, specificity, PPV, and NPV of MDCT for lymph node metastasis were 50%, 75%, 43%, and 80%, respectively.

CONCLUSIONS

The diagnostic accuracy of MDCT for tumor location and vertical invasion was satisfactory, but ductal spread was underestimated in comparison with microscopic measurements.

Elevated CA 19-9 portends poor prognosis in patients undergoing resection of biliary malignancies

BACKGROUND

Biliary tree malignancies including cholangiocarcinoma and gallbladder cancer are aggressive cancers with a high disease-specific mortality despite resection. The aim of the present study was to identify predictors of survival after resection.

METHODS

A retrospective review of all patients that underwent radical resection of biliary malignancies was performed. Demographics, elevated CA19-9 (>35 U/ml), treatment and outcome data were collected and compared according to tumour location. Kaplan-Meier survival curves were created and compared using log-rank analysis. Multivariate analysis was undertaken using Cox proportional hazards regression.

RESULTS

Ninety-one patients with biliary malignancies underwent surgical resection between 1992 and 2007. There were 46 (50.5%) extrahepatic cholangiocarcinomas (EHC), 23 (25.2%) intrahepatic cholangiocarcinomas (IHC) and 22 (24.2%) gallbladder carcinomas (GBC). The median (range) age was 64 (24-92) years. An elevated CA19-9 was recorded in 45 (55%) patients (52% of IHC, 63% of EHC, and 41% of GBC). The overall median (range) survival was 22.5 (0.3-153.3) months. All three groups were similar in terms of age, gender, pre-operative CA 19-9 level, completeness of resection and tumour histopathological characteristics. GBC were associated with the shortest median survival (14.3 months) followed by EHC (24.8 months) and IHC (30.4 months); however, this did not meet statistical significance (P= 0.971). Only elevated pre-operative CA 19-9 level (>35 U/ml) was predictive of poor median survival by univariate (P= 0.003) and multivariate analysis (15.1 months vs. 67.4, P= 0.047).

CONCLUSIONS

Elevated pre-operative CA 19-9 levels were found to be independent predictors of poor survival after attempted resection for biliary tree malignancies. It is recommended that CA19-9 be routinely measured prior resection.

Application of Portal Parenchyma–Enterostomy after High Hilar Resection for Bismuth Type IV Hilar Cholangiocarcinoma

For the surgical treatment of Bismuth Type IV hilar cholangiocarcinoma, it is difficult to achieve curative resection (R0 resection) with restrictive excision (local resection and parenchyma-preserving liver resection) as a result of the complexity and difficulty in biliary reconstruction. Extended hepatectomy with vessel resection can improve the rate of curative resection, but it can also give rise to postoperative complications and mortality. We proposed a high hilar resection and portal parenchyma–enterostomy method to improve the surgical procedure. Eleven patients with Bismuth IV hilar cholangiocarcinoma underwent high hilar resection (resection for tumors in bile ducts and 1 cm above the tumors including segments IVb, V, and part of the caudate liver lobe) and the biliary tract was reconstructed through a portal parenchyma–enterostomy. Biliary radicles were not ligated but were drained into the “bile lake.” No cases of perioperative death were observed. Four weeks after surgery, patients’ serum aspartate aminotransferase, alanine aminotransferase, and total bilirubin were decreased evidently. The average survival was 25.3 months. In conclusion, the portal parenchyma–enterostomy procedure can be performed with increased curative rate and reduced parenchyma resection, extending the survival time of patients and improving patients’ quality of life.

Value of multidetector row CT in the assessment of longitudinal extension of cholangiocarcinoma: correlation between MDCT and microscopic findings

BACKGROUND

A few authors have reported the value of multidetector row CT (MDCT) for evaluating the longitudinal extent of cholangiocarcinoma. They have not focused on CT attenuation of a tumor and actual tumor extent along the bile ducts. We designed the present study to analyze attenuation.

METHODS

Between January 2003 and July 2005, 113 consecutive patients with cholangiocarcinoma underwent a surgical resection following MDCT. Of these MDCT studies, 73 (perihilar cholangiocarcinoma, n = 62; middle and distal cholangiocarcinoma, n = 11) were suitable for analysis, and the patients were enrolled in the study. Patients were divided according to tumor hypoattenuation and hyperattenuation on MDCT. Histologic differentiation, desmoplastic reaction, and vascular density were microscopically compared with the tumor attenuation to differentiate the characteristics of the attenuation. The extent of cancer along the bile duct diagnosed by MDCT was compared with the actual extent determined by the microscopic findings.

RESULTS

Hyperattenuated tumor was observed in 40 patients. There was no difference in histologic differentiation, desmoplastic reaction, or vascular density between the hyperattenuated and hypoattenuated cholangiocarcinomas. Neither the proximal nor the distal borders between the normal and thickened bile duct wall could be determined in the 33 patients with hypoattenuated tumor; in contrast, an accurate assessment of extent of tumor was obtained in 76% of the proximal borders and 82% of the distal borders in the 40 patients with hyperattenuated tumor.

CONCLUSIONS

Although the cause of the difference between the hyperattenuated and hypoattenuated cholangiocarcinoma still is unclear, MDCT can be an alternative to direct cholangiography in selected patients with hyperattenuated cholangiocarcinoma.

Exact CT-based liver volume calculation including nonmetabolic liver tissue in three-dimensional liver reconstruction

Exact preoperative determination of the liver volume is of great importance prior to hepatobiliary surgery, especially in living donated liver transplantation (LDLT) and extended hepatic resections. Modern surgery-planning systems estimate these volumes from segmented image data. In an experimental porcine study, our aim was (1) to analyze and compare three volume measurement algorithms to predict total liver volume, and (2) to determine vessel tree volumes equivalent to nonmetabolic liver tissue. Twelve porcine livers were examined using a standardized three-phase computed tomography (CT) scan and liver volume was calculated computer-assisted with the three different algorithms. After hepatectomy, livers were weighed and their vascular system plasticized followed by CT scan, CT reconstruction and re-evaluation of total liver and vessel volumes with the three different algorithms. Blood volume determined by the plasticized model was at least 1.89 times higher than calculated by multislice CT scans (9.7% versus 21.36%, P=0.028). Analysis of 3D-CT-volumetry showed good correlation between the actual and the calculated liver volume in all tested algorithms with a high significant difference in estimating the liver volume between Heymsfield versus Heidelberg (P=0.0005) and literature versus Heidelberg (P=0.0060). The Heidelberg algorithm reduced the measuring error with deviations of only 1.2%. The present results suggest a safe and highly predictable use of 3D-volumetry in liver surgery for evaluating liver volumes. With a precise algorithm, the volume of remaining liver or single segments can be evaluated exactly and potential operative risks can therefore be better calculated. To our knowledge, this study implies for the first time a blood pool, which corresponds to nonmetabolic liver tissue, of more than 20% of the whole liver volume.

Interactive determination of robust safety margins for oncologic liver surgery

OBJECTIVE

Complex oncologic interventions in the liver require an extensive and careful preoperative analysis. Particularly the achievement of an optimal safety margin around tumors remains a difficult task for surgeons.

METHODS

We present new methods for evaluating different safety margins and their effect on the associated interruption of vascular supply or drainage. The characteristic of vascular risk distributions can be evaluated in real-time by exploiting precomputed safety maps that provide a volume curve for each vascular system. By applying fast visualization methods in 3D it is possible to assist the surgeon in the determination of a tumor-free safety margin while preserving sufficient vital hepatic parenchyma. The combination of risk analysis from different vascular systems and their sensitivity is considered.

RESULTS

We provide physicians with a novel computer-aided planning tool that allows for interactive determination of safety margins in real-time. The planning tool integrates smoothly into the preoperative workflow. Preliminary evaluations confirm that the width of safety margins can be determined more precisely, which may affect the proposed resection strategy.

CONCLUSION

Our new methods provide interactive feedback and support for decision making during the preoperative planning stage and thus might potentially improve the outcome of surgical interventions.

Addition of hepatectomy decreases liver recurrence and leads to long survival in hilar cholangiocarcinoma

AIM: To evaluate hepatic recurrence and prognostic factors for survival in patients with surgically resected hilar cholangiocarcinoma in a single institution over the last 13 years.

METHODS: From 1994 to 2007, all patients with hilar cholangiocarcinoma referred to a surgical clinic were evaluated. Demographic data, tumor characteristics, and outcome were analyzed retrospectively. Outcome was compared in patients who underwent additional liver resection with resection of the tumor.

RESULTS: Of the 69 patients submitted to laparotomy for tumor resection, curative resection (R₀ resection) was performed in 40 patients, and palliative resection in 29. Thirty-one patients had only duct resection, and 38 patients had combined duct resection with liver resection including 34 total or part caudate lobes. Curative rates with the combined hepatectomy were significantly improved compared with those without additional hepatectomy (27/38 vs 13/31; χ² = 5.94, P < 0.05). Concomitant liver resection was associated with a decreased incidence of initial recurrence in liver one year after surgery (11/38 vs 23/31; χ² = 13.98, P < 0.01). The 3-year survival rate after R₀ resection was 30.7% and was 10.5% for palliative resection. R₀ resection improved the 3-year survival rate (30.7% vs 10.5%; χ² = 12.47, P < 0.01).

CONCLUSION: Hepatectomy, especially including the caudate lobe combined with bile duct resection should be considered standard treatment to cure hilar cholangiocarcinoma.

Role of Sonazoid-enhanced three-dimensional ultrasonography in the evaluation of percutaneous radiofrequency ablation of hepatocellular carcinoma

OBJECTIVE

We investigated contrast-enhanced three-dimensional ultrasonography (CE 3D US) with contrast agent Sonazoid for evaluating the effect of percutaneous radiofrequency (RF) ablation of hepatocellular carcinomas (HCCs).

METHODS

63 HCCs were treated by US-guided percutaneous RF ablation. CE 3D US after bolus injection of 0.2 mL of Sonazoid was performed 5-7 days before and 1 day after RF ablation. CE 3D computed tomography (CT) was performed 5-7 days before and 1 month after the ablation, and during the follow-up period. Multiplanar images in three orthogonal planes and US/CT angiograms were reconstructed on both modalities. Two blinded observers reviewed the images on both modalities to evaluate the ablation effects.

RESULTS

After RF ablation, the evaluation on CE 3D US and that on CE 3D CT achieved concordance in 61 lesions. Among them, 59 lesions were detected with the absence of tumor vessels and tumor enhancement and evaluated as adequate ablation, and the remaining two lesions were detected with residual tumors. The kappa value for agreement between the findings on the two modalities was 0.65. When 1-month CE 3D CT scans were used as reference standard, the sensitivity, specificity, and accuracy of 1-day CE 3D US for detecting adequate ablation were 97%, 100%, and 97%, respectively.

CONCLUSION

By demonstrating the ablated areas and residual tumors in three dimensions, CE 3D US with Sonazoid was shown to be useful for evaluating the effect of RF ablation of HCCs, and there was good concordance with the results obtained by CE 3D CT.

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.

Proximal biliary malignancy

Hilar cholangiocarcinoma is a rare malignancy that occurs at the bifurcation of the bile ducts. Complete surgical excision with negative histologic margins remains the only hope for cure or long-term survival. Because of its location and proximity to the vascular inflow of the liver, surgical resection is technically difficult and may require advanced vascular reconstructions to achieve complete excision. Patients who are not candidates for resection should undergo palliative biliary drainage. The role of neoadjuvant therapy and liver transplantation in the management of hilar cholangiocarcinoma remains to be defined in light of the recent promising results.

Hilar cholangiocarcinoma: role of preoperative imaging with sonography, MDCT, MRI, and direct cholangiography

OBJECTIVE

The purpose of this article is to describe the roles of sonography, MDCT, MRI, and direct cholangiography in the evaluation of hilar cholangiocarcinoma.

CONCLUSION

Hilar cholangiocarcinoma is a primary malignant tumor typically located at the confluence of the right and left ducts within the porta hepatis. Staging of hilar cholangiocarcinoma with various imaging techniques is crucial for management, and a comprehensive approach is needed for accurate preoperative assessment.

Clinical significance of intraoperative bile duct margin assessment for hilar cholangiocarcinoma

BACKGROUND

Frozen section analysis of bile duct margins is often used to guide the extent of surgical resection for hilar cholangiocarcinoma (HCCA), but the usefulness of this practice is unknown.

METHODS

The association between disease-specific survival (DSS) and pathologic margin status determined during and after surgical resection for HCCA was assessed retrospectively for 101 patients between 1992 and 2005. Final histopathology identified three subgroups on the basis of resection margin status: wide margin (bile duct and specimen margins negative for adenocarcinoma), narrow margin (bile duct margin negative but specimen margins positive), and positive margin (bile duct and specimen margins positive).

RESULTS

On the basis of frozen section analysis alone, 90 patients were thought to have a disease-negative bile duct margin intraoperatively. Final histopathology showed that eight patients (9%) had invasive adenocarcinoma in the cuff of bile duct submitted for frozen section analysis. Of the 82 patients with negative final bile duct margins, 54 patients were categorized as having wide margins, and 28 patients had narrow margins. The median DSS for patients with wide margins was 56 months compared with 38 months for patients with narrow margins and 32 months for margin-positive patients (P = .01).

CONCLUSION

Frozen section analysis of the proximal bile duct margin is misleading in 9% of patients. Among patients with HCCA who are determined to have negative duct margins intraoperatively, only 60% will have margins adequately wide enough to be associated with an improvement in DSS.