Endoscopic ultrasound criteria for vascular invasion in the staging of cancer of the head of the pancreas: a blind reevaluation of videotapes

BACKGROUND: It has been claimed in several prospective studies that endoscopic ultrasonography (EUS) is highly accurate in the locoregional staging of pancreatic cancer. However, the value of the EUS criteria for the diagnosis of vascular involvement is less well established. To totally exclude potential bias introduced by the availability of prior information, a completely blinded analysis of videotapes of patients with cancer of the pancreatic head was therefore conducted. METHODS: Videotape sequences of 75 patients with cancer of the head of the pancreas with surgical confirmation or unequivocally positive angiography demonstrating vascular invasion were reevaluated without any clinical data or information from other imaging studies. Involvement of the vascular system (portal vein with confluence, superior mesenteric vein, celiac axis) was assessed on EUS with special emphasis on EUS parameters of the tumor-vessel relationship. RESULTS: The overall sensitivity and specificity of EUS in the diagnosis of venous invasion were 43% and 91%, respectively, when using predetermined parameters (visualization of tumor in the lumen, complete obstruction, or collateral vessels). If the parameter "irregular tumor-vessel relationship" had been added to these criteria, the sensitivity would have risen to 62%, but the specificity would have fallen to 79%. The only vascular system that could be properly visualized by EUS was the portal vein/confluence area. The positive and negative predictive values for the single parameters chosen to diagnose portal venous involvement were as follows: 42% and 33% for irregular tumor-vessel relationship, 36% and 34% for visualization of tumor in the vascular lumen, 80% and 28% for complete vascular obstruction, and 88% and 18% for collateral vessels. CONCLUSIONS: In a completely blinded evaluation of the EUS diagnosis of vascular invasion by cancer of the head of the pancreas it was not possible to find suitable morphologic parameters with clinically useful sensitivity and specificity values (over 80%).     

Power Doppler ultrasonography for the assessment of vascular invasion by pancreatic cancer

Aim: To investigate the diagnostic accuracy of power Doppler ultrasonography (US) in assessing the vascular invasion by pancreatic cancer. Methods: A prospective study of 40 consecutive patients with pancreatic cancer (head 35, body 5) was performed. All patients underwent surgery. The relationships between tumor and each vessel were classified into four types according to the closest circumferential contact of the tumor with the vessel. A type 0 indicated no contact; type 1 indicated less than one third contact; type 2 indicated one third to 99% contact, and type 3 indicated encasement. Vascular invasion was diagnosed in types 2 and 3. The diagnostic accuracy was evaluated in the portal vein and in the splanchnic arteries (celiac artery, common hepatic artery, and superior mesenteric artery). The power Doppler US findings were confirmed by the operative findings. The results of power Doppler US were compared with those of CT scan and angiography. Results: Portal vein invasion was confirmed in resected specimens in 23 cases and by operative findings in 5 cases. For the diagnosis of portal vein invasion, sensitivity, specificity, and overall accuracy of power Doppler US were, respectively, 79.3, 90.9, and 82.5%. The respective values were 79.3, 100, and 85% for CT and 72.4, 81.8, and 75% for angiography. For the diagnosis of arterial invasion, sensitivity, specificity, and overall accuracy of power Doppler US were 80, 92, and 90%, respectively. The corresponding values were 47, 88, and 73% for CT and 47, 100, and 80% for angiography. Conclusion: Power Doppler US proved to be useful for the diagnosis of vascular invasion by pancreatic cancer.     

Diagnostic accuracy of EUS for vascular invasion in pancreatic and periampullary cancers: a meta-analysis and systematic review

BACKGROUND: Vascular invasion (VI) in a patient with pancreatic or periampullary cancers precludes surgery and indicates a poor prognosis. Published data on the accuracy of EUS in diagnosing VI is varied. OBJECTIVE: The aim of this meta-analysis was to evaluate the accuracy of EUS in diagnosing VI in patients with pancreatic and periampullary cancers. DESIGN: Data from EUS studies were pooled according to the Mantel-Haenszel and DerSimonian Laird methods. PATIENTS: EUS studies in which VI was confirmed by surgery or angiography were selected. INTERVENTIONS: EUS. MAIN OUTCOME MEASURES: Pooled estimates of sensitivity, specificity, likelihood ratios, and diagnostic odds ratio of EUS. RESULTS: Data were extracted from 29 studies (N = 1308) that met the inclusion criteria. The pooled sensitivity of EUS in diagnosing VI was 73% (95% CI, 68.8-76.9) and the pooled specificity was 90.2% (95% CI, 87.9-92.2). The positive likelihood ratio for diagnosing VI by EUS was 9.1 (95% CI, 4.6-17.9) and the negative likelihood ratio was 0.3 (95% CI, 0.2-0.5). Diagnostic odds ratio, the odds of having VI in positive as compared with negative EUS studies, was 40.1 (95% CI, 16.1-99.9). The P value for chi(2) heterogeneity for all the pooled estimates was >.05. CONCLUSIONS: Although EUS is the best noninvasive test to diagnose VI in pancreatic and periampullary cancers, this meta-analysis showed that the specificity (90%) is high but the sensitivity (73%) is not as high as suggested. Further refinements in EUS technologies and interpretation may improve the sensitivity for detecting VI.     

ENDOSCOPIC ULTRASOUND AND FINE‐NEEDLE ASPIRATION FOR PANCREATIC CANCER

Background: Accurate staging of pancreatic cancer is essential for surgical planning, and identification of locally advanced and metastatic disease that is incurable by surgery. Advances in EUS, CT, and PET have improved the accuracy of staging and reduced the number of incomplete surgical resections. Tissue acquisition is necessary in non‐surgical cases when chemo‐radiotherapy is considered. The complex regional anatomy of the pancreas makes cytologic diagnosis of malignancy at this region difficult without exploratory surgery. Although CT‐guided fine‐needle aspiration (FNA) is used for this purpose, reports of an increased risk of peritoneal dissemination of cancer cells and a false negative rate of nearly 20% makes this a less than ideal choice. The ability to position the EUS‐transducer in direct proximity to the pancreas by means of stomach and the duodenum, combined with the use of FNA, increases the specificity of EUS in detecting pancreatic malignancies. Methods: The current literature regarding the accuracy of EUS with FNA in the evaluation of pancreatic cancer is reviewed. Results: EUS accuracy for tumor (T) staging ranges from approximately 78–94% and nodal (N) stage accuracy between 64 and 82%. EUS also enables FNA of lesions that are too small to be identified by CT or MRI, or too close to vascular structures to safely allow percutaneous biopsy. The accuracy for detecting invasion into the superior mesenteric artery and vein is lower than that for detecting portal or splenic vein invasion, especially for large tumors. EUS permits delivery of localized therapy such as celiac plexus neurolysis for pain control and direct intralesional injection of antitumor therapy. Conclusions: EUS in combination with FNA is a highly accurate method of preoperative staging of pancreatic cancer especially those too small to characterize by CT or MRI, and has the ability to obtain cytological confirmation.     

EUS, PET, and CT scanning for evaluation of pancreatic adenocarcinoma

BACKGROUND: Preoperative diagnosis of pancreatic adenocarcinoma can be difficult. Computed tomography (CT) is the standard, noninvasive imaging method for evaluation of suspected pancreatic adenocarcinoma, but it has limited sensitivity for diagnosis, local staging, and metastases. Endoscopic ultrasound (EUS) and fluoro-deoxyglucose/positron emission tomography (FDG-PET) are imaging methods that may improve diagnostic accuracy. METHODS: Thirty-five patients with presumed resectable pancreatic adenocarcinoma were prospectively evaluated with helical CT, EUS, and FDG-PET. RESULTS: Sensitivity for the detection of pancreatic cancer was higher for EUS (93%) and FDG-PET (87%) than for CT (53%). EUS was more sensitive than CT for local vascular invasion of the portal and superior mesenteric veins. EUS diagnosis of vascular invasion was associated with poor outcome after surgery. EUS-guided, fine-needle aspiration allowed tissue diagnosis in 14 of 21 attempts (67%). FDG-PET diagnosed 7 of 9 cases of proven metastatic disease, 4 of which were missed by CT. Two of three metastatic liver lesions suspected by CT were indeterminate for metastases. FDG-PET confirmed metastases. CONCLUSIONS: EUS and PET improve diagnostic capability in pancreatic adenocarcinoma. EUS is useful in determining local vascular invasion and obtaining tissue diagnosis. FDG-PET is useful in identifying metastatic disease. Both techniques are more sensitive than helical CT for identification of the primary tumor. (Gastrointest Endosc 2000;52:367-71).     

Endosonography is superior to angiography in the preoperative assessment of vascular involvement among patients with pancreatic carcinoma

Surgical exploration in patients with pancreatic carcinoma without adequate preoperative attempts to determine resectability results in resection in only a minority of patients. Besides distant metastases, involvement of the major vessels is the most important parameter for determining resectability in patients with pancreatic adenocarcinoma. Angiography has been an integral part of pancreatic cancer staging. Lately, endoscopic ultrasound (EUS) has emerged as a more accurate tool in the diagnosis and staging of pancreatic cancer. We hypothesize that EUS is more accurate than selective venous angiography (SVA) for assessing resectability of pancreatic adenocarcinoma based on preoperative evaluation of vascular involvement. Twenty-one patients who met the inclusion criteria were prospectively evaluated with both EUS and SVA before undergoing surgical exploration for attempted curative resection. Vascular involvement was determined by EUS and SVA using previously described criteria. The sensitivity, specificity, and overall accuracy of EUS and SVA in assessing vascular involvement were compared, using surgical exploration as the gold standard. Endoscopic ultrasound had a higher sensitivity than SVA for detecting vascular involvement (86% vs. 21%, respectively; p = 0.0018). The specificity and accuracy of EUS for detecting vascular involvement was 71% and 81%, respectively. In contrast, the specificity and accuracy of SVA for detecting vascular involvement was 71% and 38%, respectively. Endoscopic ultrasound is significantly more sensitive than angiography for detecting vascu lar involvement in patients with pancreatic adenocarcinoma and, thus, may improve patient selection for attempted curative resection.     

Endoscopic ultrasound and upper gastrointestinal disorders

Endoscopic ultrasound (EUS) plays a vital role in management of upper gastrointestinal disorders, particularly cancer of the esophagus, pancreas, stomach, lung (via transesophageal mediastinal staging), and bile duct. Endoscopic ultrasound has also been valuable in detection of early chronic pancreatitis (CP). In cancer of the esophagus, the primary role of EUS is to determine whether disease is localized (T1-2, N0) and appropriate for surgery, locally advanced (T3-4, N1, M1a) (which may benefit from chemoradiation with or without surgery), or metastatic. Pancreatic and bile duct cancers are more complex given the controversy over portal vein resection. In centers that resect tumors invading the portal venous system, the role of EUS is limited to tissue confirmation or identification of metastases to the liver or distant lymph nodes. In centers that do not resect the portal vein invasion, EUS plays an important role in local staging. In lung cancer, EUS is emerging as an accurate, nonsurgical alternative to staging the mediastinum through EUS fine-needle aspiration. Endoscopic ultrasound has an important role in diagnosing CP because of its high degree of sensitivity. This has also led to controversy over whether EUS can overdiagnose CP. For these reasons, we recommend the use of a high threshold for EUS and that CP be diagnosed in conjunction with other standard tests (endoscopic retrograde cholangiopancreatography, pancreatic function tests).     

Non-invasive diagnosis of portal vein occlusion by radionuclide angiography.

The accuracy of non-invasive radionuclide angiography in detecting portal vein occlusion was assessed in 61 patients--10 with portal vein occlusion confirmed by conventional portography, 25 with chronic liver disease and a patent portal vein (mild = 12, severe = 13), and 26 with normal liver function, who served as controls. The median percentage portal venous flow for the portal vein occlusion group was 8% (range 1-30) (consistent with negligible flow) compared with 78% (52-87) for control subjects (p < 0.005) and 68% (61-80) and 49% (23-59) respectively for patients with mild and severe liver disease (p < 0.001 and p < 0.005). At a portal venous inflow of < 20%, the procedure had a specificity of 100% and sensitivity of 90% in diagnosing portal vein occlusion. Non-invasive radionuclide angiography provides a safe and accurate screening method for evaluating portal vein patency or occlusion in the investigation of portal hypertension or before liver transplantation.     

Intraoperative diagnosis of pancreatic cancer extension using IVUS

BACKGROUND/AIMS: Pancreatic cancer easily invades retroperitoneal tissue, especially the portal vein and extrapancreatic nerve plexus. We evaluated the diagnostic accuracy of intraportal endovascular ultrasonography in portal vein and extrapancreatic nerve plexus invasion. METHODOLOGY: Intraportal endovascular ultrasonography was performed in 78 cases of pancreatic cancer (head 67, body 8, total 3). Intraportal endovascular ultrasonography was performed intraoperatively from the superior mesenteric vein with an 8-French, 20-MHz intravascular ultrasound catheter. Three-dimensional intraportal endovascular ultrasonography was constructed by volume rendering. RESULTS: Intraportal endovascular ultrasonography visualized the portal vein as an echogenic band with a thickness of 0.5 mm to 1.0 mm. The diagnostic criterion of portal vein invasion was obliteration of this echogenic band. Intraportal endovascular ultrasonography visualized segment II of the extrapancreatic nerve plexus as the high-echoic area around the inferior pancreaticoduodenal artery. The diagnostic criterion of extrapancreatic nerve plexus invasion was low-echoic infiltration around the inferior pancreaticoduodenal artery. The sensitivity, specificity, and overall accuracy of intraportal endovascular ultrasonography for diagnosis of portal vein invasion was, respectively, 97.4%, 92.5%, and 94.9%. The values for diagnosis of extrapancreatic nerve plexus invasion, respectively, were 94.4%, 97.1%, and 96.2%. Three-dimensional intraportal endovascular ultrasonography depicted the invasion area as a defect of the portal vein wall. CONCLUSIONS: Intraportal endovascular ultrasonography detected subtle portal invasion and provided accurate portal invasion area which was useful for portal vein an reconstruction. Intraportal endovascular ultrasonography could also diagnose the extrapancreatic nerve plexus invasion of segment II.     

Does mesenteric venous imaging assessment accurately predict pathologic invasion in localized pancreatic ductal adenocarcinoma?

Background

Accurate prediction of mesenteric venous involvement in pancreatic ductal adenocarcinoma (PDAC) is necessary for adequate staging and treatment.

EUS diagnosis of vascular invasion in pancreatic cancer: surgical and histologic correlates

BACKGROUND: Endoscopic ultrasound (EUS) has been compared to intraoperative surgical palpation for diagnosis of vascular invasion by pancreatic cancer. This study compares EUS with vascular resection and histologic evidence of vascular invasion in resected pancreatic masses. METHODS: All patients with solid pancreatic masses who underwent both preoperative EUS and surgery at 1 hospital over a 7 year period were identified. The relationship of pancreatic masses to adjacent vessels was prospectively assessed by EUS. EUS findings were compared to surgical and pathology gold standards. "Vascular adherence" was defined as tumor adherence requiring vascular resection during surgery, and "vascular invasion" as histologic invasion of vessel wall by tumor. RESULTS: 30 of 68 patients were resectable. Among these 30, vascular adherence was present in 8, including 18% of patients with an intact echoplane between tumor and adjacent vessels at EUS, 29% of those with loss of echoplane alone, and 50% of those with additional EUS features of vascular involvement. Vascular invasion was present in 4, including 12% of patients with an intact echoplane, 0% of those with loss of echoplane alone, and 33% of those with additional EUS features. Sensitivity, specificity, PPV, and NPV of EUS were 63%, 64%, 43% and 80% for vascular adherence and 50% 58%, 28% and 82% for vascular invasion. NPV rose to 90% for vascular adherence if only the portal confluence vessels were considered. CONCLUSIONS: EUS has poor sensitivity, specificity, and positive predictive value for diagnosis of venous involvement by pancreatic cancer.     

Modification and establishment of CT criteria in preoperative assessment of portal venous invasion by hilar cholangiocarcinoma

Background

To compare the diagnostic performance of CT criteria and to establish a new model in evaluating portal venous invasion by hilar cholangiocarcinoma.

Signiifcance of pathological positive superior mesenteric/portal venous invasion in pancreatic cancer

BACKGROUND: Pancreaticoduodenectomy with superior mesenteric/portal venous resection for pancreatic ductal ad-enocarcinoma (PDAC) is frequently performed with no added morbidity or mortality in case of tumor abutment to the su-perior mesenteric or portal vein so as to obtain a margin nega-tive resection. True histopathological portal vein invasion is found only in a small subset of such patients. The aim of this review aimed to discuss the signiifcance of histopathological venous invasion in PDAC.
DATA SOURCES: For this review available data was searched from PubMed and analyzed. No randomized trials have been published on this topic.
RESULTS: Existing data on prognostic factors in histopatho-logical venous invasion by PDAC are limited and recent stud-ies indicate worse survival in this subgroup of patients. In addition, venous invasion in PDAC has been associated with large tumors, involved lymph nodes, perineural invasion and R1 resection. The survival of patients with portal venous re-section but without histologic venous invasion is reportedly better than those with histopathological venous invasion;though conlficting studies do exist on the subject. Some stud-ies also relate the depth of venous invasion to prognosis after surgical resection of PDAC.
CONCLUSIONS: Frank/‘histopathological’ invasion of supe-rior mesenteric/portal venous and R1 resection indicate a very poor survival. Such patients may be given the opportunity of beneift of neoadjuvant treatment.     

Preoperative diagnosis and staging of pancreatic cancer by endoscopic ultrasonography (EUS)--a comparative study with other diagnostic tools]

Endoscopic ultrasonography (EUS), ultrasonography (US), computed tomography (CT), and angiography (Angio) were performed in 26 patients with pancreatic cancer which were all resected. Preoperative findings of each diagnostic tools were compared with histological findings. In order to discuss the effectiveness of each body imagings, the preoperative staging of pancreatic cancer was evaluated in direct invasion to the anterior pancreatic capsule and stomach (S), direct invasion to the duodenum (D), direct invasion to the retroperitoneal adjacent vessels (Rp), and regional lymph node metastasis (N). The overall accuracy rate was 77% with EUS (50% with US, 38% with CT, 56% with Angio) in S, 81% with EUS (44% with US, 38% with CT, 63% with Angio) in D, 77% with EUS (58% with US, 42% with CT, 73% with Angio) in Rp, and 65% with EUS (58% with US, 38% with CT) in N. EUS revealed high accuracy rates because EUS images of the whole pancreas, surrounding organs and major vessels were clearly visualized through the gastroduodenal walls. Also, the accuracy rates of Angio in Rp and US in N were almost the same as those of EUS in Rp and N. However, it was difficult for every procedure to diagnose the retroperitoneal perineural invasion. From these results, EUS is one of the most beneficial procedures for detecting of the extent of cancer. EUS is expected to be popularized in the diagnosis and staging of the pancreatic cancer.     

Role of endoscopic ultrasound in the diagnosis of patients with solid pancreatic masses

Endoscopic ultrasound (EUS) is the most sensitive imaging procedure for the detection of small solid pancreatic masses and is accurate in determining vascular invasion of the portal venous system. Even compared to the new CT techniques, EUS provides excellent results in preoperative staging of solid pancreatic tumors. Compared to helical CT techniques, EUS is less accurate in detecting tumor involvement of the superior mesenteric artery. EUS staging and EUS-guided FNA can be performed in a single-step procedure, to establish the diagnosis of cancer. There is no known negative impact of tumor cell seeding due to EUS-guided fine needle aspiration (FNA). Without FNA, EUS and additional methods are not able to reliably distinguish between inflammatory and malignant masses.     

Endoscopic ultrasound is a sensitive and specific test to diagnose portal venous system thrombosis (PVST)

OBJECTIVES: Thrombosis of the portal venous system (PVS) may complicate cirrhosis, pancreatitis, malignancies, and hypercoagulable states. Computed tomography (CT) scanning can diagnose thrombi present in the lumen of the PVS, but is probably insensitive. Endoscopic ultrasound (EUS) may be a more sensitive test for diagnosing PVS thrombosis (PVST). We sought to determine the accuracy of EUS for the diagnosis of PVST. METHODS: Using a retrospective analysis of patients' studies retrieved from a database at Massachusetts General Hospital, we determined the sensitivity and specificity of EUS in 16 patients with PVST and 29 without PVST as proven by surgery and/or CT scanning. All patients underwent a linear EUS exam of the PVS and the results of the EUS report were used as the basis of the study. RESULTS: The sensitivity of EUS for the finding of PVST was 81% in 13 of 16 patients and the specificity was 93% in 27 of 29 patients with an overall accuracy of 89% (40/45). In an additional group of 11 patients, EUS demonstrated the presence of a PVST that was not detected by CT scanning. CONCLUSION: Linear EUS is a highly sensitive and specific test for PVST.     

Diagnosis of pT2 gallbladder cancer by serial examinations with endoscopic ultrasound and angiography

Background. The prognosis of pT2 gallbladder cancer correlates with whether appropriate surgery for the spread of cancer has been performed. Therefore, accurate preoperative T staging is especially important. We carried out this study to evaluate the usefulness of serial examinations by endoscopic ultrasound (EUS) and angiography for the T staging of pT2 gallbladder cancer. Methods. Forty-eight patients with gallbladder cancer who underwent both EUS and surgery between 1983 and 1998 were included in this study. The accuracy of serial examination by both EUS and angiography in T staging, based on previously established diagnostic criteria, was retrospectively evaluated. First, the presence or absence of subserosal tumor invasion was assessed by EUS alone. Second, in equivocal cases, the depth of tumor invasion was further evaluated by angiographic findings. Results. Twenty-four patients were correctly diagnosed as having other than pT2 cancer by EUS alone. Angiographic findings were reviewed in 19 of the remaining patients, who had pT1, pT2, or a small number of pT3 lesions. The sensitivity, specificity, and overall accuracy in the T staging of pT2 gallbladder cancer was 81.8%, 90.6%, and 88.4%, respectively. Conclusions. Serial angiographic examination following adequate patient selection by EUS is effective and efficient for the diagnosis of pT2 gallbladder cancer. Received: March 19, 2001 / Accepted: September 14, 2001     

Endoscopic ultrasonography in diagnosis and staging of pancreatic cancer

The accuracy of endoscopic ultrasonography (EUS) for diagnosis of pancreatic cancers was evaluated in consecutive 232 patients with possible pancreatic cancer, and that for assessment of their locoregional spread was evaluated in 28 patients with pancreatic cancer subjected to pancreatectomy, in comparison with the accuracies of transabdominal ultrasonography (US) and computed tomography (CT). EUS was found to be significantly more accurate than US or CT and was especially useful for detecting small pancreatic cancers of less than 2 cm in diameter. With EUS, pancreatic cancers could be detected as a hypoechoic mass with a relatively unclear margin and irregular internal echoes. EUS was also more sensitive than CT and US for detecting venous and gastric invasions: it was more useful for detecting direct invasion of pancreatic cancers when the tumors were less than 3 cm in diameter. These findings indicate that EUS is an accurate method for diagnosis of pancreatic cancer and assessment of their locoregional spread and is particularly useful for detecting small tumors.     

Pancreaticoduodenectomy with portal vein/superior mesenteric vein resection for patients with pancreatic cancer with venous invasion

BACKGROUND: With the development of new surgical techniques, pancreaticoduodenectomy(PD) with portal vein or superior mesenteric vein(PV/SMV) resection has been used in the treatment of patients with borderline resectable pancreatic cancer. However, opinions of surgeons differ in the effectiveness of this surgical technique. This study aimed to investigate the effectiveness of this approach in patients with pancreatic cancer.METHODS: Follow-up visits and retrospective analysis were carried out of 208 patients with pancreatic cancer who had undergone PD(PD group) and PD combined with PV/SMV resection and reconstruction(PDVR group) from June 2009 to May 2013 at our center. Statistical analysis was performed to compare the clinical features, the difference of survival time and risk factors of venous invasion in pancreatic cancer.Factors relating to postoperative survival time of pancreatic cancer were also investigated. RESULTS: In the PDVR group, which consisted of 42 cases, the 1-,2- and 3-year survival rates were 70%, 41% and 16%, respectively and the median survival time was 20.0 months. Among the 166 patients in the PD group, the 1-, 2- and 3-year survival rates were 80%, 52%, and 12%, respectively with the median survival time of 26.0 months. No significant difference in survival time and R0 resection ratio was found between the two groups. Lumbodorsal pain, tumor with pancreatic capsular invasion and bile duct infiltration were found to be independent risk factors for PV invasion in pancreatic cancer. In addition, non R0 resection,large tumor size(2 cm) and poorly differentiated tumor were independent risk factors for survival time in post-PD.CONCLUSIONS: The tumor has a higher chance of venous invasion if preoperative imagings indicate that it juxtaposes with the vessel. Lumbodorsal pain is the chief complaint. Patients with pancreatic cancer associated with PV involvement should receive PDVR for R0 resection when preoperational assessment shows the chance for eradication.     

Computed tomography in the evaluation of the portal venous system.

Computed tomography has widespread clinical application in the evaluation of the portal venous system, even though quantitative methods are impractical due to the inability to measure portal flow discrete from hepatic arterial flow, morbidity associated with the use of large volumes of iodinated contrast, and technical limitations. This represents a major disadvantage compared to Doppler ultrasound and magnetic resonance angiography. Qualitative applications include evaluation of portal vein patency, diagnosis of portal vein thrombosis, underlying inflammatory or neoplastic conditions, and evaluation of surgically created portosystemic shunts and collateral flow. Diagnostic criteria for portal venous thrombosis include nonopacification of the central portion of the portal vein, peripheral enhancement of the vein, and irregular periportal hepatic parenchymal enhancement. However, misdiagnosis is common, occurring in 16% of cases analyzed in one limited series, and periportal vein enhancement is now recognized as a nonspecific finding associated with underlying endothelial injury. Cavernous transformation of the portal vein and neoplastic invasion of the portal system are more reliably recognized. Computed tomography arterial portography demonstrates collateral pathways and arteriovenous shunts. Computed tomography has a sensitivity of 85% in detection of esophageal varices compared to endoscopy, but has the advantage of demonstrating splenorenal, gastrorenal, peripancreatic, pericholecystic, retroperitoneal and omental collateral vessels, and spontaneous large portosystemic shunts, with greater sensitivity than angiography. Computed tomography combined with Doppler ultrasound angiography remains popular, despite a lack of large-scale prospective efficacy studies demonstrating diagnostic superiority over other imaging techniques, largely because of its accessibility, and its detailed axial anatomic images providing an overview of multiple organ systems, and patency of major vessels.