Expression of collagenase (MMP2), stromelysin (MMP3) and tissue inhibitor of the metalloproteinases (TIMP1) in pancreatic and ampullary disease.

It is now recognised that epithelial-stromal interactions are important in a wide range of disease processes including neoplasia and inflammation. Metalloproteinases are central to matrix degradation and remodelling, which are key events in tumour invasion and metastasis and may also be involved in tissue changes occurring in chronic inflammation. Immunohistochemistry was performed on sections from 50 patients with pancreatic cancer (n = 27), ampullary cancer (n = 12), low bile duct cancer (n = 3), neuroendocrine tumours (n = 3) and chronic pancreatitis (n = 5), using antibodies raised against collagenase (MMP2), stromelysin (MMP3) and tissue inhibitor of metalloproteinase (TIMP1) and developed using the avidin-biotin complex method. Abundance of MMP2, MMP3 and TIMP1 was greater in pancreatic and ampullary cancer than any other pathology and immunoreactivity in the malignant epithelial cells in pancreatic and ampullary cancer was greater than in the stromal tissues (in pancreatic cancer: MMP2 100% vs 37%, MMP3 93% vs 15%, TIMP1 93% vs 4%, P < 0.0001). There were strong correlations between the immunoreactivity of the two antibodies for MMP2 (P < 0.0001), between MMP2 and TIMP1 (P < 0.0001) and between MMP3 and TIMP1 (P < 0.0001). The immunoreactivity for TIMP1 in pancreatic and ampullary cancers with lymph node metastases was significantly less compared with those cases without lymph node metastases (P < 0.02) and there was an association between increased immunoreactivity for MMP2 and the degree of tumour differentiation (P < 0.01). The results implicate MMP2, MMP3 and TIMP1 in the invasive phenotype of pancreatic and ampullary cancer

A double-blind placebo-controlled, randomised study comparing gemcitabine and marimastat with gemcitabine and placebo as first line therapy in patients with advanced pancreatic cancer

Pancreatic cancer is the fifth most common cause of cancer death in the western world and the prognosis for unresectable disease remains poor. Recent advances in conventional chemotherapy and the development of novel ‘molecular’ treatment strategies with different toxicity profiles warrant investigation as combination treatment strategies. This randomised study in pancreatic cancer compares marimastat (orally administered matrix metalloproteinase inhibitor) in combination with gemcitabine to gemcitabine alone. Two hundred and thirty-nine patients with unresectable pancreatic cancer were randomised to receive gemcitabine (1000 mg m−2) in combination with either marimastat or placebo. The primary end-point was survival. Objective tumour response and duration of response, time to treatment failure and disease progression, quality of life and safety were also assessed. There was no significant difference in survival between gemcitabine and marimastat and gemcitabine and placebo (P=0.95 log-rank test). Median survival times were 165.5 and 164 days and 1-year survival was 18% and 17% respectively. There were no significant differences in overall response rates (11 and 16% respectively), progression-free survival (P=0.68 log-rank test) or time to treatment failure (P=0.70 log-rank test) between the treatment arms. The gemcitabine and marimastat combination was well tolerated with only 2.5% of patients withdrawn due to presumed marimastat toxicity. Grade 3 or 4 musculoskeletal toxicities were reported in only 4% of the marimastat treated patients, although 59% of marimastat treated patients reported some musculoskeletal events. The results of this study provide no evidence to support a combination of marimastat with gemcitabine in patients with advanced pancreatic cancer. The combination of marimastat with gemcitabine was well tolerated. Further studies of marimastat as a maintenance treatment following a response or stable disease on gemcitabine may be justified

A phase I and pharmacological study of the matrix metalloproteinase inhibitor BB-3644 in patients with solid tumours.

BB-3644 is an oral, broad-spectrum matrix metalloproteinase inhibitor (MMPI) structurally related to marimastat and BB-94. It is also >10-fold more active than marimastat in inhibiting the processing of cell-bound TNF-alpha. Preclinical studies suggested a favourable toxicity profile when compared to marimastat, and therefore it was selected for clinical evaluation. Patients with advanced solid tumours against which established treatments had failed, or for which no satisfactory treatment exists and of good performance status, were eligible. Treatment consisted of twice daily (bd) oral BB-3644 for 84 days. The initial dose was 5 mg bd, and subsequent cohorts were treated with 10, 20 and 30 mg bd. In all, 22 patients were enrolled. The dose-limiting toxicity (DLT) was musculoskeletal pain. For 28 days of treatment with BB-3644, 20 mg bd was the maximum tolerated dose (MTD), as at 30 mg bd, six of nine patients developed significant musculoskeletal toxicity by day 28. Following chronic oral dosing (>28 days) with BB-3644, three of five patients treated at 10 mg bd developed musculoskeletal DLT by day 84, defining the MTD as 5 mg bd. As dose-limiting musculoskeletal toxicity was encountered at doses of BB-3644 unlikely to provide an advantage over currently available MMPIs, further evaluation is not recommended

A preoperative predictive score of pancreatic fistula following pancreatoduodenectomy

AbstractBackgroundVarious factors are related to the occurrence of postoperative pancreatic fistula (POPF) following pancreatoduodenectomy (PD). Some of the strongest are identified intra- or postoperatively, which limits their utility in predicting this complication. The preoperative prediction of POPF permits an individualized approach to patient consent and selection, and may influence postoperative management. This study sought to develop and test a score to predict POPF.MethodsA post hoc analysis of a prospectively maintained database was conducted. Consecutive patients were randomly selected to modelling and validation sets at a ratio of 2:1, respectively. Patient data, preoperative blood tests and physical characteristics of the gland (assessed from preoperative computed tomography images) were subjected to univariate and multivariate analysis in the modelling set of patients. A score predictive of POPF was designed and tested in the validation set.ResultsPostoperative pancreatic fistula occurred in 77 of 325 (23.7%) patients. The occurrence of POPF was associated with 12 factors. On multivariate analysis, body mass index and pancreatic duct width were independently associated with POPF. A risk score to predict POPF was designed (area under the receiver operating characteristic curve: 0.832, 95% confidence interval 0.768–0.897; P < 0.001) and successfully tested upon the validation set.ConclusionsPreoperative assessment of a patient's risk for POPF is possible using simple measurements. The present risk score is a valid tool with which to predict POPF in patients undergoing PD

How severe is diabetes after total pancreatectomy?:A case-matched analysis

OBJECTIVES: Total pancreatectomy (TP) is associated with significant morbidity and mortality. The severity of postoperative diabetes and existence of ‘brittle diabetes’ are unclear. This study sought to identify quality of life (QoL) and diabetes-specific outcomes after TP. METHODS: Patients who underwent TP were matched for age, sex and duration of diabetes with patients with type 1 diabetes. General QoL was assessed using the European Organization for Research and Treatment of Cancer (EORTC) core quality of life questionnaire QLQ-C30 and the PAN26 tool. Diabetes-specific outcomes were assessed using the Problem Areas in Diabetes (PAID) tool and an assessment of diabetes-specific complications and outcomes. RESULTS: A total of 123 patients underwent TP; 88 died (none of diabetic complications) and two were lost to follow-up. Of the remaining 33 patients, 28 returned questionnaires. Fourteen general and pancreas-specific QoL measurements were all significantly worse amongst the TP cohort (QLQ-C30 + PAN26). However, when diabetes-specific outcomes were compared using the PAID tool, only one of 20 was significantly worse. HbA1c values were comparable (P = 0.299), as were diabetes-related complications such as hypoglycaemic attacks and organ dysfunction. CONCLUSIONS: Total pancreatectomy is associated with impaired QoL on general measures compared with that in type 1 diabetes patients. Importantly, however, there was almost no significant difference in diabetes-specific outcomes as assessed by a diabetes-specific questionnaire, or in diabetes control. This study does not support the existence of ‘brittle diabetes’ after TP

Analytic results for Gaussian wave packets in four model systems: I. Visualization of the kinetic energy

Using Gaussian wave packet solutions, we examine how the kinetic energy is distributed in time-dependent solutions of the Schrodinger equation corresponding to the cases of a free particle, a particle undergoing uniform acceleration, a particle in a harmonic oscillator potential, and a system corresponding to an unstable equilibrium. We find, for specific choices of initial parameters, that as much as 90% of the kinetic energy can be localized (at least conceptually) in the `front half' of such Gaussian wave packets, and we visualize these effects.Comment: 22 pages, RevTeX, four .eps figures, to appear in Found. Phys. Lett. Vol. 17, Dec. 200

Modelling prognostic factors in advanced pancreatic cancer

Pancreatic cancer is the fifth most common cause of cancer death. Identification of defined patient groups based on a prognostic index may improve the prediction of survival and selection of therapy. Many prognostic factors have been identified often based on retrospective, underpowered studies with unclear analyses. Data from 653 patients were analysed. Continuous variables are often simplified assuming a linear relationship with log hazard or introducing a step function (dichotomising). Misspecification may lead to inappropriate conclusions but has not been previously investigated in pancreatic cancer studies. Models based on standard assumptions were compared with a novel approach using nonlinear fractional polynomial (FP) transformations. The model based on FP-transformed covariates was most appropriate and confirmed five previously reported prognostic factors: albumin, CA19-9, alkaline phosphatase, LDH and metastases, and identified three additional factors not previously reported: WBC, AST and BUN. The effects of CA19-9, alkaline phosphatase, AST and BUN may go unrecognised due to simplistic assumptions made in statistical modelling. We advocate a multivariable approach that uses information contained within continuous variables appropriately. The functional form of the relationship between continuous covariates and survival should always be assessed. Our model should aid individual patient risk stratification and the design and analysis of future trials in pancreatic cancer

A phase II irinotecan–cisplatin combination in advanced pancreatic cancer

We report a cisplatin and irinotecan combination in patients with biopsy-proven advanced pancreatic adenocarcinoma. Patients were selected from a specialist centre and required good performance status (KPS&gt;70%), measurable disease on CT scan, and biochemical and haematological parameters within normal limits. Based on a two-stage phase II design, we aimed to treat 22 patients initially. The study was stopped because of the death of the 19th patient during the first treatment cycle, with neutropenic sepsis and multiorgan failure. A total of 89 treatments were administered to 17 patients. Serious grade 3/4 toxicities were haematological (neutropenia) 6%, diarrhoea 6%, nausea 7% and vomiting 6%. Using the clinical benefit response (CBR) criteria, no patients had an overall CBR. For responses confirmed by CT examination, there was one partial response (5%), three stable diseases lasting greater than 6 weeks (16%), with an overall 22% with disease control (PR+SD). The median progression-free and overall survival was 3.1 months (95% CI: 1.3-3.7) and 5.0 (95% CI: 3.9-10.1) months, respectively. Although this synergistic combination has improved the response rates and survival of other solid tumours, we recommend caution when using this combination in the palliation of advanced pancreatic cancer, because of unexpected toxicity

Explicit solution for a Gaussian wave packet impinging on a square barrier

The collision of a quantum Gaussian wave packet with a square barrier is solved explicitly in terms of known functions. The obtained formula is suitable for performing fast calculations or asymptotic analysis. It also provides physical insight since the description of different regimes and collision phenomena typically requires only some of the terms.Comment: To be published in J. Phys.