Malignancy in chronic pancreatitis: analysis of diagnostic procedures and proposal of a clinical algorithm.

BACKGROUND: Pancreatic ductal adenocarcinoma (PDAC) is characterized by its poor prognosis, and some benign conditions and syndromes, including chronic pancreatitis (CP), are risk factors for pancreatic carcinoma. However, the differential diagnosis of CP from PDAC is difficult for clinicians because PDAC frequently causes inflammation within the pancreas. Therefore, patients with CP exhibit not only an elevated risk of cancer, but they are also in danger of underdiagnosis. METHODS: The present study retrospectively analyzed 29 patients with pancreatic cancer who fulfilled our definition of "chronic pancreatitis" to identify characteristics to aid in the differential diagnosis between chronic pancreatitis with and without pancreatic cancer. All parameters were subjected to univariate analysis. RESULTS: We identified several factors that differed significantly between the CP patients and patients with CP and synchronous PDAC, and these characteristics were used to develop a diagnostic algorithm. The performance of the algorithm was externally validated in a different panel of patients from the Department of Surgery, Medical Faculty Mannheim. CONCLUSION: The present study succeeded in identifying characteristics that significantly differed in patients with and without PDAC in CP. These characteristics were integrated in a diagnostic algorithm that might help to improve diagnostic of PDAC in CP.

Transabdominal contrast-enhanced ultrasonography of pancreatic cancer.

Since its introduction, contrast-enhanced ultrasonography (CEUS) has significantly extended the value of ultrasonography (US). CEUS can be used to more accurately determine pancreatic lesions compared to conventional US or to characterize lesions already detectable by US. Thus, CEUS can aid in the differential diagnosis of pancreatic tumors. Using US contrast media, it is possible to visually detect microvessels in the majority of pancreatic ductal adenocarcinomas. Thus, the use of quantitatively evaluated transabdominal CEUS can help in the differentiation of patients with mass-forming pancreatitis from patients with pancreatic adenocarcinomas. In neuroendocrine pancreatic tumors, different enhancement patterns can be observed in relation to the tumor mass: larger ones show a rapid early enhancement sometimes combined with necrotic central structures, and smaller ones disclose a capillary-blush enhancement. Pseudocysts, the most widespread cystic lesions of the pancreas, are not vascularized. They do not show any signal in CEUS and remain entirely anechoic in all phases, while true cystic pancreatic tumors usually have vascularized septa and parietal nodules. In summary, CEUS is effective for differentiating solid pancreatic tumors in most cases. CEUS is safe and cost effective and can better discriminate solid from cystic pancreatic lesions, thereby directing further imaging modalities.

Quantitative perfusion analysis of transabdominal contrast-enhanced ultrasonography of pancreatic masses and carcinomas.

BACKGROUND & AIMS: Preoperative differential diagnosis of pancreatic ductal adenocarcinoma (PDAC) and focal masses in patients with chronic pancreatitis (CP) can be challenging. There are fine differences in the vascularization of these lesions; ultrasound contrast agents can aid in their differentiation. We evaluated the value of software-aided quantitative analysis of transabdominal contrast-enhanced ultrasonography for differential diagnosis of PDAC vs focal masses. METHODS: Sixty patients for whom it was not possible to differentiate between an inflammatory focal lesion of the pancreas and a pancreatic carcinoma underwent contrast-enhanced ultrasonography with a second-generation contrast agent. Time-intensity curves were obtained for all exams in 2 regions of interest within the lesion and within the normal pancreatic tissue. Images were processed using Axius ACQ software; the following parameters were obtained: maximum intensity, arrival time, time-to-peak, and area under the curve. Absolute values and differences between the lesion and the normal tissue were evaluated. RESULTS: Histology analysis revealed 45 PDACs and 15 inflammatory masses in patients with CP. Time-dependent parameters (arrival time and time to peak) were significantly longer in PDACs compared to focal masses. Although markedly lower than in healthy pancreata, the maximum intensity and area under the curve parameters were not significantly different between PDACs and focal lesions in patients with CP. CONCLUSIONS: In cases of CP, PDAC and focal masses exhibit different perfusion patterns at a capillary level that can be visualized using the small microbubbles of ultrasound contrast agents. Contrast quantification software supplements a subjective visual assessment with objective criteria to facilitate the differential diagnosis of focal lesions in pancreatic cancer and chronic pancreatitis.

Colorectal liver metastasis surgery: analysis of risk factors predicting postoperative complications in relation to the extent of resection.

BACKGROUND/AIMS: Despite advances in diagnosis and treatment, the rate of complications after resection for colorectal liver metastases remains high. An awareness of risk factors is essential for the rates of morbidity and mortality to fall to optimal levels. MATERIALS AND METHODS: Of the 240 patients who underwent resection for the first manifestation of colorectal liver metastases, 49 patients with lobectomy or extended hepatectomy (major resections) and 58 with wedge resections within only one liver segment (minor resections) form the basis of this report. A total of 16 variables were analyzed to find the risk factors linked to postoperative morbidity and mortality. RESULTS/FINDINGS: Thirty-four patients (31.8%) suffered postoperative complications, and one patient died during the hospital stay (0.9%). In the major resection group, multivariate analysis showed that neoadjuvant chemotherapy [odds ratio (OR): 2.4; p = 0.005], vascular clamping (OR: 1.4; p = 0.008), and intraoperative blood loss with transfusion of three to six packed red cell units (OR: 1.2; p = 0.029) were significantly associated with postoperative morbidity. Vascular clamping was an independent predictor for biliary fistula (OR: 1.2; p = 0.029). Postoperative temporary liver failure was influenced by neoadjuvant chemotherapy (OR: 3.4; p = 0.010), vascular clamping (OR: 1.5; p = 0.015), and requirement of blood transfusion (OR: 2.1; p = 0.016). After minor resections, only a decreased postoperative serum cholinesterase B level was an independent predictor for complications (OR: 2.2; p = 0.001), as well as for hemorrhage (OR: 1.6; p = 0.023). Postoperative mortality was not predicted by any of the factors that were analyzed. INTERPRETATION/CONCLUSION: Factors for complications differ depending on the extent of colorectal liver metastasis resection. Only knowledge and particular consideration of these factors may provide for an optimal postoperative outcome for the individual patient.

Color Doppler imaging predicts portal invasion by pancreatic adenocarcinoma.

BACKGROUND: Tumor infiltration of the intima of the portal vein (PV) and superior mesenteric vein (SMV) by pancreatic adenocarcinoma is classically considered a criterion for unsuitability for resection and poor prognosis. This study was performed to evaluate modern color duplex imaging (CDI) for the assessment of PV/SMV infiltration by pancreatic adenocarcinomas. METHOD: From 1994 to 2005, Whipple's procedure or pylorus-preserving pancreato-duodenectomy (PPPD) was performed in 303 patients with pancreatic adenocarcinoma; 35 of these underwent partial PV/SMV resection. Applying a previously reported CDI score, we evaluated the integrity of the echogenic border layer between the vein and tumor (mural demarcation) and maximum blood flow velocity (V (max)) in the PV segment in contact with the tumor. The results were compared to the final histological findings in the resected venous walls. RESULTS: CDI findings correlated well with the histological invasion grades. By measuring V (max )and evaluating mural demarcation, we observed a sensitivity of 66.7% and 100% and a specificity of 98.3% and 93.9%, respectively, in predicting full thickness vein invasion, including the intima. V (max) above 80 cm/s and lack of mural demarcation were predictors of PV/SMV invasion. The postoperative survival rates depended on the depth of tumor infiltration into the PV/SMV. CONCLUSIONS: Modern CDI is a reliable and valid technique for evaluation of morphological and hemodynamic parameters in the portal vein segment adjacent to pancreatic adenocarcinoma. Maximal blood-flow velocity in the portal segment in contact with the tumor and absence of the echogenic vessel-parenchymal sonographic interface are parameters predictive of tumor infiltration of the portal intima.

Assessment of metastatic liver disease in patients with primary extrahepatic tumors by contrast-enhanced sonography versus CT and MRI.

AIM: To evaluate contrast-enhanced ultrasonography (CEUS) using SonoVue in the detection of liver metastases in patients with known extrahepatic primary tumors versus the combined gold standard comprising CT, MRI and clinical/histological data. METHODS: It is an international multicenter study, and there were 12 centres and 125 patients (64 males, 61 females, aged 59+/-11 years) involved, with 102 patients per protocol. Primary tumors were colorectal in 35%, breast in 27%, pancreatic in 17% and others in 21%. CEUS using SonoVue was employed with a low-mechanical-index technique and contrast-specific software using Siemens Elegra, Philips HDI 5000 and Acuson Sequoia; continuous scanning for at least five minutes. RESULTS: CEUS with SonoVue increased significantly the number of focal liver lesions detected versus unenhanced sonography. In 31.4% of the patients, more lesions were found after contrast enhancement. The total numbers of lesions detected were comparable with CEUS (55), triple-phase spiral CT (61) and MRI with a liver-specific contrast agent (53). Accuracy of detection of metastatic disease (i.e. at least one metastatic lesion) was significantly higher for CEUS (91.2%) than for unenhanced sonography (81.4%) and was similar to that of triple-phase spiral CT (89.2%). In 53 patients whose CEUS examination was negative, a follow-up examination 3-6 mo later confirmed the absence of metastatic lesions in 50 patients (94.4%). CONCLUSION: CEUS is proved to be reliable in the detection of liver metastases in patients with known extrahepatic primary tumors and suspected liver lesions.

Contrast-enhanced ultrasonography in pancreas transplantation.

BACKGROUND: Pancreas transplantation remains a major surgery with potential complications that require reliable imaging despite impaired kidney function. Contrast-enhanced ultrasonography (CEUS) has been proven to be an indispensable tool in the evaluation of the native pancreas. Here, CEUS studies are extended to pancreas transplants for the first time. METHODS: A total of 42 B-mode, duplex, and CEUS exams performed using 1 mL SonoVue (Bracco) on a Siemens Acuson Sequoia ultrasound machine were evaluated in 14 pancreas transplant recipients. Time-intensity curves and curve characteristics were calculated. The data were compared between normal pancreas transplants, grafts undergoing rejection, and grafts after successful treatment of the rejection episode. RESULTS: All of the grafts could be well visualized in all ultrasound exams. Although the arterial resistive index did not differentiate between rejection and the absence of rejection, in CEUS, the time-intensity curves showed a significantly slower ascent and diminished maximum intensity in pancreas grafts during rejection, with significantly reduced maximum intensity and time to reach peak intensity. After the successful treatment of rejection, these parameters were almost restored to initial values. DISCUSSION: CEUS displays the capillary perfusion of the tissue. Edema of the pancreas graft during rejection impairs capillary perfusion, reflected in the amount of contrast detected by CEUS and the dynamics of the influx of the contrast agent. CONCLUSION: CEUS yields useful information after pancreas transplantation and has been proven a sensitive tool in the surveillance of pancreas grafts. Further studies will be needed to differentiate rejection from other posttransplantation complications using CEUS.

Ultrasonographic classification of achilles tendon ruptures as a rationale for individual treatment selection.

Purpose. This work introduces a distinct sonographic classification of Achilles tendon ruptures which has proven itself to be a reliable instrument for an individualized and differentiated therapy selection for patients who have suffered an Achilles tendon rupture. Materials and Methods. From January 1, 2000 to December 31, 2005, 273 patients who suffered from a complete subcutaneous rupture of the Achilles tendon (ASR) were clinically and sonographically evaluated. The sonographic classification was organized according to the location of the rupture, the contact of the tendon ends, and the structure of the interposition between the tendon ends. Results. In 266 of 273 (97.4%) patients the sonographic classification of the rupture of the Achilles tendon was recorded. Type 1 was detected in 54 patients (19.8%), type 2a in 68 (24.9%), type 2b in 33 (12.1%), type 3a in 20 (7.3%), type 3b in 61 (22.3%), type 4 in 20 (7.3%), and type 5 in 10 (3.7%). Of the patients with type 1 and fresh ASR, 96% (n = 47) were treated nonoperative-functionally, and 4% (n = 2) were treated by percutaneous suture with the Dresden instrument (pDI suture). Of the patients classified as type 2a with fresh ASR, 31 patients (48%) were treated nonoperatively-functionally and 33 patients (52%) with percutaneous suture with the Dresden instrument (pDI suture). Of the patients with type 3b and fresh ASR, 94% (n = 34) were treated by pDI suture and 6% (n = 2) by open suture according to Kirchmayr and Kessler. Conclusion. Unlike the clinical classification of the Achilles tendon rupture, the sonographic classification is a guide for deriving a graded and differentiated therapy from a broad spectrum of treatments.

Prospective evaluation of ultrasound and colour duplex imaging for the assessment of surgical resectability of pancreatic tumours.

BACKGROUND: This study was performed to evaluate colour duplex imaging (CDI) for the assessment of resectability of pancreatic tumours (PTs). METHOD: From October 1998 to December 2001, 182 patients consecutively having surgery for a PT were enrolled in this prospective study. Extension of the tumour to large blood vessels and retroperitoneum, the detection of liver metastases, enlarged lymph nodes and peritoneal carcinomatosis were defined as criteria for assessment. The patients were grouped into three classes of resectability: US-TU 1 = resectable/potentially curable, US-TU 2 = questionably resectable/curable, and US-TU 3 = non-resectable/not curable. CDI was performed by five different examiners. Results were compared with intra-operative findings. RESULTS: Using CDI, we classified 85 (46.7%) tumours as resectable, 64 (35.2%) as non-resectable, and 33 (18.1%) as questionably resectable. Overall, 46.2% ( n=84) were found to be resectable, and 53.8% ( n=98) to be non-resectable, intra-operatively. A correlation between CDI classification and intra-operative findings was found in 138 of 149 cases (92.6%) (sensitivity 88.4%, specificity 96.3%). With regard to the complete oncological status (local extension, metastases, lymph-node staging and peritoneal carcinomatosis), a sensitivity of 77.2% and specificity of 95.7% were found. Non-correlated findings were likely attributed to missing small liver metastases, peritoneal carcinomatosis without ascites, and on difficulties in the assessment of enlarged lymph nodes concerning tumour infiltration. CONCLUSION: The use of CDI in evaluation of PTs may provide valuable pre-operative assessment of surgical resectability and may be performed in the clinical setting.