Jae Bok Chung

Perfusion CT: Noninvasive Surrogate Marker for Stratification of Pancreatic Cancer Response to Concurrent Chemo- and Radiation Therapy

PURPOSE To prospectively determine whether perfusion computed tomography (CT) parameters, such as volume transfer constant (K(trans)) between blood plasma and extracellular extravascular space (EES) and blood volume calculated from dynamic CT data, can be used to predict response of pancreatic cancer to concurrent chemotherapy and radiation therapy (CCRT). MATERIALS AND METHODS This prospective study was institutional review board approved, and written informed consent was obtained. Thirty patients with pancreatic cancer underwent perfusion CT with 64-detector row CT before gemcitabine-based CCRT. Two perfusion parameters (K(trans) and blood volume) measured before treatment were compared between patients who responded to treatment and those who did not, as determined with World Health Organization criteria from first and second posttherapeutic follow-up CT examinations, which were performed at 3- and 6-month follow-up. Statistical analysis was performed with the two-sample t test. A receiver operating characteristic curve was used to determine the best cutoff value of perfusion parameters for differentiation of responders from nonresponders. RESULTS Twenty of 30 patients examined at 3-month follow-up responded to therapy. Their pretreatment K(trans) value was significantly higher than that of nonresponders (50.8 mL/100 mL/min +/- 30.5 [standard deviation] vs 19.0 mL/100 mL/min +/- 10.8, P = .001). The best cutoff value for differentiating between responders and nonresponders was 31.8 mL/100 mL/min, which yielded 75.0% sensitivity and 90.0% specificity. Ten of 18 patients examined at 6-month follow-up responded to therapy. Their pretreatment K(trans) value was significantly higher than that of nonresponders (58.6 mL/100 mL/min +/- 43.2 vs 19.8 mL/100 mL/min +/- 10.9, P = .002). Responders also had higher blood volume values, but this difference was not significant. CONCLUSION Tumors with a high pretreatment K(trans) value tended to respond better to CCRT than did tumors with a low pretreatment K(trans) value. Perfusion CT may be used to predict tumor response to CCRT in patients with pancreatic cancer. This might aid in development of a tailored approach to therapy in these patients.

Recanalization of refractory benign biliary stricture using magnetic compression anastomosis

BACKGROUND AND STUDY AIMS Endoscopic or percutaneous treatments are preferentially attempted for benign biliary stricture (BBS). However, these methods are not feasible if a guide wire cannot be passed through the stricture. This study evaluated the usefulness and technical requirements of magnetic compression anastomosis (MCA) in refractory BBS. PATIENTS AND METHODS MCA was performed in patients with BBS that had not been resolved with conventional treatments. One magnet was delivered through the percutaneous transhepatic biliary drainage tract and the other magnet was advanced through three different routes. After magnet approximation and recanalization, an internal drainage catheter was placed for 6 months and then removed. RESULTS Seven patients underwent MCA, and recanalization was successfully achieved in five. MCA failure in two cases was attributed to long stenotic segments and parallel alignment of the axes of the magnets. The mean follow-up period after recanalization was 485.2 days. Five patients with successful recanalization showed no MCA-related complications or restenosis. CONCLUSIONS MCA represents an alternative nonsurgical method of BBS recanalization that cannot be treated with conventional methods.

Prognostic factors and characteristics of pancreatic neuroendocrine tumors: single center experience.

Purpose Pancreatic neuroendocrine tumors (PNET) are a rare subgroup of tumors. For PNETs, the predictive factors for survival and prognosis are not well known. The purpose of our study was to evaluate the predictive factors for survival and disease progression in PNETs. Materials and Methods We retrospectively analyzed 37 patients who were diagnosed with PNET at Severance Hospital between November 2005 and March 2010. Prognostic factors for survival and disease progression were evaluated using the Kaplan-Meier method. Results The mean age of the patients was 50.0±15.0 years. Eight cases (21.6%) were described as functioning tumors and 29 cases (78.4%) as non-functioning tumors. In univariate analysis of clinical factors, patients with liver metastasis (p=0.002), without resection of primary tumors (p=0.002), or American Joint Committee on Cancer/Union for International Cancer Control (AJCC/UICC) stage III/IV (p=0.002) were more likely to demonstrate shorter overall survival (OS). Patients with bile duct or pancreatic duct invasion (p=0.031), sized-lesions larger than 20 mm (p=0.036), liver metastasis (p=0.020), distant metastasis (p=0.005), lymph node metastasis (p=0.009) or without resection of primary tumors (p=0.020) were more likely to demonstrate shorter progression-free survival (PFS). In multivariate analysis of clinical factors, bile duct or pancreatic duct invasion [p=0.010, hazard ratio (HR)=95.046] and tumor location (non-head of pancreas) (p=0.036, HR=7.381) were confirmed as independent factors for predicting shorter PFS. Conclusion Patients with liver metastasis or without resection of primary tumors were more likely to demonstrate shorter OS. Patients with bile duct or pancreatic duct invasion or tumors located at body or tail of pancreas were more likely to demonstrate shorter PFS.

Efficacy of Adjuvant Chemotherapy and Prognostic Factors for Patients with Extrahepatic Bile Duct Cancer

Background: Surgical resection is the only curative treatment for extrahepatic bile duct cancer. Additionally, the recurrence rate after curative surgery is relatively high, requiring adjuvant therapy. However, the efficacy of adjuvant chemotherapy compared with surgery alone has not yet been clarified. This study aimed to evaluate the efficacy of adjuvant chemotherapy and identify prognostic factors influencing survival in extrahepatic bile duct cancer patients who underwent curative surgical resection. Methods: Ninety-seven patients with extrahepatic bile duct cancer who underwent curative resection between January 2005 and December 2010 were retrospectively analyzed. Results: Among the 97 patients, 31 underwent adjuvant chemotherapy and 66 did not. The 5-year overall survival rate was 34% for patients who underwent adjuvant chemotherapy. There was no significant difference for overall survival between patients who underwent adjuvant chemotherapy and those who did not (p = 0.228). On multivariate analysis, postoperative carbohydrate antigen 19-9 levels and histologic grade were independent prognostic factors related to long-term survival (p < 0.05). Conclusions: Postoperative adjuvant chemotherapy did not improve survival after surgical resection for extrahepatic bile duct cancer.

Conventional versus Analgesia-Oriented Combination Sedation on Recovery Profiles and Satisfaction after ERCP: A Randomized Trial

Background The importance of providing effective analgesia during sedation for complex endoscopic procedures has been widely recognized. However, repeated administration of opioids in order to achieve sufficient analgesia may carry the risk of delayed recovery after propofol based sedation. This study was done to compare recovery profiles and the satisfaction of the endoscopists and patients between conventional balanced propofol sedation and analgesia-oriented combination sedation for patients undergoing endoscopic retrograde cholangiopancreatography (ERCP). Methods Two hundred and two adult patients scheduled for ERCP were sedated by either the Conventional (initial bolus of meperidine with propofol infusion) or Combination (repeated bolus doses of fentanyl with propofol infusion) method. Recovery profiles, satisfaction levels of the endoscopists and patients, drug requirements and complications were compared between groups. Results Patients of the Combination Group required significantly less propofol compared to the Conventional Group (135.0 ± 68.8 mg vs. 165.3 ± 81.7 mg, P = 0.005). Modified Aldrete scores were not different between groups throughout the recovery period, and recovery times were also comparable between groups. Satisfaction scores were not different between the two groups in both the endoscopists and patients (P = 0.868 and 0.890, respectively). Conclusions Considering the significant reduction in propofol dose, the non-inferiority of recovery profiles and satisfaction scores of the endoscopists and patients, analgesia oriented combination sedation may be a more safe yet effective sedative method compared to conventional balanced propofol sedation during ERCP.

Validation of Group B Borderline Resectable Pancreatic Cancer: Retrospective Analysis

Background/Aims Among borderline resectable pancreatic cancer (BRPC), group B BRPC patients have findings that are suggestive but not diagnostic of metastasis. In this study, we attempted to validate whether group B could truly be categorized as a borderline resectable group. Methods We placed the BRPC patients into group A or group B. The survival outcomes were compared between the groups. Results A total of 53 patients with pancreatic adenocarcinoma was classified as either group A or B borderline resectable. In group A, 23 (60.5%) of 38 patients underwent pancreatectomy after concurrent chemoradiotherapy or chemotherapy, but in group B, only five (33.3%) of 15 patients underwent pancreatectomy, mainly because of the progression of suspected distant metastasis. There was a significant difference in overall survival (OS) between group A and B patients (median OS, 21.2 months vs 10.2 months, respectively; p=0.007). Of the patients who underwent pancreatectomy, group B had a higher recurrence rate compared to group A (recurrence rate: 11 of 23 patients [47.8%] vs five of five patients [100%], respectively; p=0.033). Conclusions This report is the first to validate the definition of BPRC. Group B had much worse outcomes, and whether group B BRPC can be categorized as BRPC together with group A is questionable.