Impact of expanding indications on surgical and oncological outcome in 1434 consecutive pancreatoduodenectomies.

BACKGROUND: Over the years, high-volume pancreatic centers expanded their indications for pancreatoduodenectomy (PD) but with unknown impact on surgical and oncological outcome. METHODS: All consecutive PDs performed between 1992-2017 in a single pancreatic center were identified from a prospectively maintained database and analyzed according to three time periods. RESULTS: In total, 1434 patients underwent PD. Over time, more elderly patients underwent PD (P < 0.001) with increased use of vascular resection (10.4 to 16.0%, P < 0.001). In patients with cancer (n = 1049, 74.8%), the proportion pT3/T4 tumors increased from 54.3% to 70.6% over time (P < 0.001). The postoperative pancreatic fistula (16.0%), postpancreatectomy hemorrhage (8.0%) and delayed gastric emptying (31.0%) rate did not reduce over time, whereas median length of stay decreased from 16 to 12 days (P < 0.001). The overall failure-to-rescue rate (6.9%) and in-hospital mortality (2.2%) remained stable (P = 0.89 and P = 0.45). In 523 patients with pancreatic cancer (36.5%), the use of both adjuvant and neoadjuvant chemotherapy increased over time (both p<0.001), and the five-year overall survival improved from 11.0% to 17.4% (P < 0.001). CONCLUSIONS: In a period where indications for PD expanded, with more elderly patients, more advanced cancers and increased use of vascular resections, surgical outcome remained favorable and five-year survival for pancreatic cancer improved.

Computed tomography findings after radiofrequency ablation in locally advanced pancreatic cancer.

PURPOSE: The purpose of the study was to provide a systematic evaluation of the computed tomography(CT) findings after radiofrequency ablation (RFA) in locally advanced pancreatic cancer(LAPC). METHODS: Eighteen patients with intra-operative RFA-treated LAPC were included in a prospective case series. All CT-scans performed prior to RFA and 1 week and 3 months of post-RFA, according to standard regimen, were assessed by two radiologists in consensus, using standardized radiological scoring lists. RESULTS: 51 CT-scans were assessed. One week after RFA, the ablation zone was visible in all patients as a (partially) sharply defined (83%), heterogeneous area (94%). At 3 months of follow-up, the ablation zone was completely invaded by tumor in 67% of patients and still present, but decreased in 33%. In two patients (11%), local thrombosis and/or occlusion of the superior mesenteric vein occurred. The occlusions persisted without clinical consequences and the thrombosis disappeared. A peripancreatic fluid collection was visible 1 week after RFA in 3 patients, wherein the ablation zone extended ventrally outside of the pancreas. CONCLUSIONS: Directly after RFA for LAPC, a well-defined ablation zone is visible on CT-imaging. This ablation zone is usually replaced by tumor ingrowth after 3 months. Moreover, the ablation zone regularly included vascular structures, with rare asymptomatic venous occlusion or thrombosis and without adverse effects on arteries.

The prognostic value of portal vein and hepatic artery involvement in patients with perihilar cholangiocarcinoma.

BACKGROUND: Although several classifications of perihilar cholangiocarcinoma (PHC) include vascular involvement, its prognostic value has not been investigated. Our aim was to assess the prognostic value of unilateral and main/bilateral involvement of the portal vein (PV) and hepatic artery (HA) on imaging in patients with PHC. METHODS: All patients with PHC between 2002 and 2014 were included regardless of stage or management. Vascular involvement was defined as apparent tumor contact of at least 180° to the PV or HA on imaging. Kaplan-Meier method with log-rank test was used to compare overall survival (OS) between groups. Cox regression was used for multivariable analysis. RESULTS: In total, 674 patients were included with a median OS of 12.2 (95% CI 10.6-13.7) months. Patients with unilateral PV involvement had a median OS of 13.3 (11.0-15.7) months, compared with 14.7 (11.7-17.6) in patients without PV involvement (p = 0.12). Patients with main/bilateral PV involvement had an inferior median OS of 8.0 (5.4-10.7, p < 0.001) months. Median OS for patients with unilateral HA involvement was 10.6 (9.3-12.0) months compared with 16.9 (13.2-20.5) in patients without HA involvement (p < 0.001). Patients with main/bilateral HA involvement had an inferior median OS of 6.9 (3.3-10.5, p < 0.001). Independent poor prognostic factors included unilateral and main/bilateral HA involvement, but not PV involvement. CONCLUSION: Both unilateral and main HA involvement are independent poor prognostic factors for OS in patients presenting with PHC, whereas PV involvement is not.

Validation of the Mayo Clinic Staging System in Determining Prognoses of Patients With Perihilar Cholangiocarcinoma.

BACKGROUND & AIMS: Most systems for staging perihilar cholangiocarcinoma (PHC) have been developed for the minority of patients with resectable disease. The recently developed Mayo Clinic system for staging PHC requires only clinical and radiologic variables, but has not yet been validated. We performed a retrospective study to validate the Mayo Clinic staging system. METHODS: We identified consecutive patients with suspected PHC who were evaluated and treated at 2 tertiary centers in The Netherlands, from January 2002 through December 2014. Baseline characteristics (performance status, carbohydrate antigen 19-9 level) used in the staging system were collected from medical records and imaging parameters (tumor size, suspected vascular involvement, and metastatic disease) were reassessed by 2 experienced abdominal radiologists. Overall survival was analyzed using the Kaplan-Meier method and comparison of staging groups was performed using the log-rank test and Cox proportional hazard regression analysis. Discriminative performance was quantified by the concordance index and compared with the radiologic TNM staging of the American Joint Committee on Cancer (7th ed). RESULTS: PHCs from 600 patients were staged according to the Mayo Clinic model (23 stage I, 80 stage II, 357 stage III, and 140 stage IV). The median overall survival time was 11.6 months. The median overall survival times for patients with stages I, II, III, and IV were 33.2 months, 19.7 months, 12.1 months, and 6.0 months, respectively; with hazard ratios of 1.0 (reference), 2.02 (95% confidence interval [CI], 1.14-3.58), 2.71 (95% CI, 1.59-4.64), and 4.00 (95% CI, 2.30-6.95), respectively (P < .001). The concordance index score was 0.59 for the entire cohort (95% CI, 0.56-0.61). The Mayo Clinic model performed slightly better than the radiologic American Joint Committee on Cancer TNM system. CONCLUSIONS: In a retrospective study of 600 patients with PHC, we validated the Mayo Clinic system for staging PHC. This 4-tier staging system may aid clinicians in making treatment decisions, such as referral for surgery, and predicting survival times.

Development of a Risk Score to Predict Detection of Metastasized or Locally Advanced Perihilar Cholangiocarcinoma at Staging Laparoscopy.

BACKGROUND: Nearly half of patients with perihilar cholangiocarcinoma (PHC) have incurable tumors at laparotomy. Staging laparoscopy (SL) potentially detects metastases or locally advanced disease, thereby avoiding unnecessary laparotomy. However, the diagnostic yield of SL has decreased with improved imaging in recent years. OBJECTIVE: The aim of this study was to identify predictors for detecting metastasized or locally advanced PHC at SL and to develop a risk score to select patients who may benefit most from this procedure. METHODS: Data of patients with potentially resectable PHC who underwent SL between 2000 and 2015 in our center were retrospectively analyzed. Multivariable logistic regression analysis was used to identify independent predictors and to develop a preoperative risk score. RESULTS: Unresectable PHC was detected in 41 of 273 patients undergoing SL (yield 15 %). Overall sensitivity of SL was 30 %, with highest sensitivity for detecting peritoneal metastases (73 %). Preoperative imaging factors that were independently associated with unresectability at SL were tumor size ≥4.5 cm, bilateral portal vein involvement, suspected lymph node metastases, and suspected (extra)hepatic metastases on imaging without the possibility of diagnosis by percutaneous- or endoscopic ultrasound-guided biopsy. The derived preoperative risk score showed good discrimination to predict unresectability (area under the curve 0.77, 95 % confidence interval 0.68-0.86) and identified three subgroups with a predicted low-risk of 7 % (N = 203 patients), intermediate-risk of 21 % (N = 39), and high-risk of 58 % (N = 31). CONCLUSIONS: A selective approach for SL in PHC is recommended since the overall yield is low. The proposed preoperative risk score is useful in selecting patients for SL.

Clinical outcomes and prevalence of cancer in patients with possible groove pancreatitis.

BACKGROUND AND AIM: Data on non-surgical treatment of groove pancreatitis (GP) and the risk of cancer are lacking. We aimed to determine the prevalence and predictors of cancer in patients in whom the diagnosis GP was considered, and to evaluate symptom improvement after treatment. STUDY: Patients referred with possible GP (2001-2014) were retrospectively included. An experienced radiologist reassessed imaging. GP patients received questionnaires evaluating their symptoms. RESULTS: From the 38 possible GP patients, 10 had cancer (26%) and 28 GP (74%). Compared with cancer patients, GP patients more frequently had cysts (2/10 vs. 18/28, P = 0.03), less often jaundice (6/10 vs 3/27, P < 0.01), an abrupt caliber change of the CBD (5/10 vs. 2/28, P < 0.01) or suspicious cytology (5/9 vs 2/20, P = 0.02). Of the 28 GP patients, 14 patients were treated conservatively of whom 12 reported symptom improvement after a median follow-up of 45 months (range 7-127 months). All 6 patients treated endoscopically and 7/8 patients treated surgically reported symptom improvement. Surgery, performed because of treatment failure (3/8) or inability to exclude malignancy (5/8), caused mortality in 1/8 patients. CONCLUSIONS: Suspicion of pancreatic cancer should be high in patients presenting with possible GP. Conservative, endoscopic and surgical treatment can all lead to symptom improvement, suggesting a 'step-up approach' to GP once cancer is excluded.

Preoperative computed tomography assessment of skeletal muscle mass is valuable in predicting outcomes following hepatectomy for perihilar cholangiocarcinoma.

BACKGROUND: Liver surgery for perihilar cholangiocarcinoma (PHC) is associated with high rates of morbidity and mortality. OBJECTIVES: This study investigated the impact of low skeletal muscle mass on short- and longterm outcomes following hepatectomy for PHC. METHODS: Patients included underwent liver surgery for PHC between 1998 and 2013. Total skeletal muscle mass was measured at the level of the third lumbar vertebra using available preoperative computed tomography images. Sex-specific cut-offs for low skeletal muscle mass were determined by optimal stratification. RESULTS: In 100 patients, low skeletal muscle mass was present in 42 (42.0%) subjects. The rate of postoperative complications (Clavien-Dindo Grade III and higher) was greater in patients with low skeletal muscle mass (66.7% versus 48.3%; multivariable adjusted P = 0.070). Incidences of sepsis (28.6% versus 5.2%) and liver failure (35.7% versus 15.5%) were increased in patients with low skeletal muscle mass. In addition, 90-day mortality was associated with low skeletal muscle mass in univariate analysis (28.6% versus 8.6%; P = 0.009). Median overall survival was shorter in patients with low muscle mass (22.8 months versus 47.5 months; P = 0.014). On multivariable analysis, low skeletal muscle mass remained a significant prognostic factor (hazard ratio 2.02; P = 0.020). CONCLUSIONS: Low skeletal muscle mass has a negative impact on postoperative mortality and overall survival following resection of PHC and should therefore be considered in preoperative risk assessment.

Expiration-phase template-based motion correction of free-breathing abdominal dynamic contrast enhanced MRI.

This paper studies a novel method to compensate for respiratory and peristaltic motions in abdominal dynamic contrast enhanced magnetic resonance imaging. The method consists of two steps: 1) expiration-phase "template" construction and retrospective gating of the data to the template; and 2) nonrigid registration of the gated volumes. Landmarks annotated by three experts were used to directly assess the registration performance. A tri-exponential function fit to time intensity curves from regions of interest was used to indirectly assess the performance. One of the parameters of the tri-exponential fit was used to quantify the contrast enhancement. Our method achieved a mean target registration error (MTRE) of 2.12, 2.27, and 2.33 mm with respect to annotations by expert, which was close to the average interobserver variability (2.07 mm). A state-of-the-art registration method achieved an MTRE of 2.83-3.10 mm. The correlation coefficient of the contrast enhancement parameter to the Crohn's disease endoscopic index of Severity (r = 0.60, p = 0.004) was higher than the correlation coefficient for the relative contrast enhancement measurements values of two observers ( r(Observer 1) = 0.29, p = 0.2; r(Observer 2) = 0.45, p = 0.04). Direct and indirect assessments show that the expiration-based gating and a nonrigid registration approach effectively corrects for respiratory motion and peristalsis. The method facilitates improved enhancement measurement in the bowel wall in patients with Crohn's disease.

Disappointing interobserver agreement among radiologists for a classifying diagnosis of pancreatic cysts using magnetic resonance imaging.

OBJECTIVES: To assess the degree of interobserver agreement of MRI in the diagnostic assessment of pancreatic cysts (PCs). METHODS: Magnetic resonance imaging sets of images of 62 patients with PCs (32 with histological confirmation and 30 with clinical diagnosis) were reviewed by 4 experienced radiologists. Features scored included septations, nodules, solid components, pancreatic duct communication, and wall thickening (>2 mm). Radiologists were asked whether they considered the PC mucinous and if the PC was suspicious for malignancy. Furthermore, they had to choose a classifying diagnosis. Intraclass correlation coefficient (ICC) was used to measure agreement within the group. RESULTS: Interobserver agreement for septations and nodules was fair (ICC, 0.36 and 0.23, respectively). Agreement for the presence of solid components was fair (ICC, 0.23), agreement for communication with the pancreatic duct was moderate (ICC, 0.53), and agreement for wall thickening was moderate (ICC, 0.44). There was fair agreement for the discrimination between mucinous and nonmucinous PC (ICC, 0.36). Agreement was fair (ICC, 0.26) for a classifying diagnosis and fair for the presence of malignant features (ICC, 0.33). CONCLUSIONS: Interobserver agreement was poor to moderate for individual PC features, and there was fair agreement for a classifying diagnosis. Magnetic resonance imaging morphology alone did not allow for a reliable discrimination between different types of PC.

Preoperative biliary drainage for cancer of the head of the pancreas.

BACKGROUND: The benefits of preoperative biliary drainage, which was introduced to improve the postoperative outcome in patients with obstructive jaundice caused by a tumor of the pancreatic head, are unclear. METHODS: In this multicenter, randomized trial, we compared preoperative biliary drainage with surgery alone for patients with cancer of the pancreatic head. Patients with obstructive jaundice and a bilirubin level of 40 to 250 micromol per liter (2.3 to 14.6 mg per deciliter) were randomly assigned to undergo either preoperative biliary drainage for 4 to 6 weeks, followed by surgery, or surgery alone within 1 week after diagnosis. Preoperative biliary drainage was attempted primarily with the placement of an endoprosthesis by means of endoscopic retrograde cholangiopancreatography. The primary outcome was the rate of serious complications within 120 days after randomization. RESULTS: We enrolled 202 patients; 96 were assigned to undergo early surgery and 106 to undergo preoperative biliary drainage; 6 patients were excluded from the analysis. The rates of serious complications were 39% (37 patients) in the early-surgery group and 74% (75 patients) in the biliary-drainage group (relative risk in the early-surgery group, 0.54; 95% confidence interval [CI], 0.41 to 0.71; P<0.001). Preoperative biliary drainage was successful in 96 patients (94%) after one or more attempts, with complications in 47 patients (46%). Surgery-related complications occurred in 35 patients (37%) in the early-surgery group and in 48 patients (47%) in the biliary-drainage group (relative risk, 0.79; 95% CI, 0.57 to 1.11; P=0.14). Mortality and the length of hospital stay did not differ significantly between the two groups. CONCLUSIONS: Routine preoperative biliary drainage in patients undergoing surgery for cancer of the pancreatic head increases the rate of complications. (Current Controlled Trials number, ISRCTN31939699.)

Does a computer-aided detection algorithm in a second read paradigm enhance the performance of experienced computed tomography colonography readers in a population of increased risk?

We prospectively determined whether computer-aided detection (CAD) could improve the performance characteristics of computed tomography colonography (CTC) in a population of increased risk for colorectal cancer. Therefore, we included 170 consecutive patients that underwent both CTC and colonoscopy. All findings >or=6 mm were evaluated at colonoscopy by segmental unblinding. We determined per-patient sensitivity and specificity for polyps >or=6 mm and >or=10 mm without and with computer-aided detection (CAD). The McNemar test was used for comparison the results without and with CAD. Unblinded colonoscopy detected 50 patients with lesions >or=6 mm and 25 patients with lesions >or=10 mm. Sensitivity of CTC without CAD for these size categories was 80% (40/50, 95% CI: 69-81%) and 64% (16/25, 95% CI: 45-83%), respectively. CTC with CAD detected one additional patient with a lesion >or=6 mm and two with a lesion >or=10 mm, resulting in a sensitivity of 82% (41/50, 95% CI: 71-93%) (p = 0.50) and 72% (18/25, 95% CI: 54-90%) (p = 1.0), respectively. Specificity without CAD for polyps >or=6 mm and >or=10 mm was 84% (101/120, 95% CI: 78-91%) and 94% (136/145, 95% CI: 90-98%), respectively. With CAD, the specificity remained (nearly) unchanged: 83% (99/120, 95% CI: 76-89%) and 94% (136/145, 95% CI: 90-98%), respectively. Thus, although CTC with CAD detected a few more patients than CTC without CAD, it had no statistically significant positive influence on CTC performance.

Lesion conspicuity and efficiency of CT colonography with electronic cleansing based on a three-material transition model.

OBJECTIVE: The purpose of this article is to report the effect on lesion conspicuity and the practical efficiency of electronic cleansing for CT colonography (CTC). MATERIALS AND METHODS: Patients were included from the Walter Reed Army Medical Center public database. All patients had undergone extensive bowel preparation with fecal tagging. A primary 3D display method was used. For study I, the data consisted of all patients with polyps > or = 6 mm. Two experienced CTC observers (observer 1 and observer 2) scored the lesion conspicuity considering supine and prone positions separately. For study II, data consisted of 19 randomly chosen patients from the database. The same observers evaluated the data before and after electronic cleansing. Evaluation time, assessment effort, and observer confidence were recorded. RESULTS: In study I, there were 59 lesions partly or completely covered by tagged material (to be uncovered by electronic cleansing) and 70 lesions surrounded by air (no electronic cleansing required). The conspicuity did not differ significantly between lesions that were uncovered by electronic cleansing and lesions surrounded by air (observer 1, p < 0.5; observer 2, p < 0.6). In study II, the median evaluation time per patient after electronic cleansing was significantly shorter than for original data (observer 1, 20 reduced to 12 minutes; observer 2, 17 reduced to 12 minutes). Assessment effort was significantly smaller for both observers (p < 0.0000001), and observer confidence was significantly larger (observer 1, p < 0.007; observer 2, p < 0.0002) after electronic cleansing. CONCLUSION: Lesions uncovered by electronic cleansing have comparable conspicuity with lesions surrounded by air. CTC with electronic cleansing sustains a shorter evaluation time, lower assessment effort, and larger observer confidence than without electronic cleansing.

Influence of tagged fecal material on detectability of colorectal polyps at CT: phantom study.

OBJECTIVE: The purpose of this study was to determine the influence of tagged material on the minimal radiation dose needed to detect colorectal polyps at CT. MATERIALS AND METHODS: The study was conducted in two phases. In the first, three experienced observers determined the visibility of sessile polyps (6 mm) at five contrast levels (300, 480, 790, and 1,040 HU and air) and five tube charge levels (10, 14, 20, 28, and 40 mAs) in an anthropomorphic phantom. Each polyp was present in one of eight possible locations. The mean tube charge threshold for 90% correct responses was determined for each contrast level. Blinded observers performed independent 2D readings. In the second phase of the study, three 150-cm virtual colons were evaluated at two contrast levels (300 and 480 HU) and at five tube charge levels between 20 and 80 mAs. The three colons contained 18 randomly located polyps. The mean tube charge threshold for 90% sensitivity was determined for each contrast level. RESULTS: In the first phase of the study, the estimated tube charge thresholds for 300, 480, and 790 HU were 24.0, 16.3, and 6.2 mAs. At 1,040 HU and in air, all polyps were detected at the lowest tube charge setting (10 mAs). In the second phase, the tube charge thresholds for 90% sensitivity at 300 and 480 HU were 70 and 35 mAs, respectively. CONCLUSION: If polyps are covered by fecal material, a considerably higher tube charge setting is needed for adequate visualization than is needed for polyps in a completely cleansed colon, especially when the density of the tagged residue is low.