Modern imaging methods versus clinical assessment in the evaluation of hospital in-patients with suspected pancreatic disease

OBJECTIVE

Various modern imaging procedures such as endoscopic retrograde cholangiopancreatography (ERCP), computed tomography (CT), and endoscopic ultrasonography (EUS) have been shown to be highly accurate in the diagnosis of specific disorders of the pancreas. However, prior information often causes bias in the interpretation of these results. Little information is available concerning the value of these examinations in the primary and differential diagnosis of suspected pancreatic disease-particularly in comparison with clinical evaluation, including laboratory tests and transabdominal ultrasound (TUS).

METHODS

Clinical and imaging information (EUS, ERCP, and CT) was collected for 184 inpatients who were referred over a 5-yr period for evaluation of suspected pancreatic disease. On the basis of patient history, laboratory tests, and the results of routine TUS, one gastroenterologist, who was unaware of any of the other procedures or the final diagnosis, made a presumptive clinical diagnosis. CT and ERCP images and EUS videotapes were then analyzed by three different and independent examiners, who had the same clinical information except for the TUS results, but were completely blinded to the results of the other examinations and the patients' diagnoses. The final diagnoses were obtained by surgery, histology, and cytology, plus a follow-up of at least 1 yr (mean 35 months) in all noncancer cases.

RESULTS

The final diagnoses were: normal pancreas (n = 36), chronic pancreatitis without a focal inflammatory mass (n = 53) or with a focal inflammatory mass (n = 18), and pancreatic malignancy (n = 77). Clinical evaluation, including ultrasonography, achieved a sensitivity for pancreatic disease of 94% but a specificity of only 35%. The figures for the sensitivity and specificity of the three imaging procedures were 93% and 94%, respectively, for EUS; 89% and 92% for ERCP; and 91% and 78% for CT (p < 0.05 for the specificity of clinical assessment vs all three imaging tests, p > 0.05 for comparison of the three imaging procedures). In the differential diagnosis between cancer and chronic pancreatitis as well as between malignant and inflammatory tumors, there was no difference among clinical assessment and the three imaging tests.

CONCLUSIONS

In a group of patients with a high suspicion of pancreatic disease, little additional sensitivity in the diagnosis of pancreatic disease is provided by sophisticated imaging procedures such as EUS, ERCP, and CT, in comparison with clinical assessment including laboratory values and TUS. However, the specificity can be substantially improved. To confirm the diagnosis, one of the three examinations is needed, depending on the suspected disease and local expertise. The imaging procedures should be performed in a stepwise fashion for specific purposes, such as exclusion of pancreatic disease and the planning of treatment in chronic pancreatitis and pancreatic cancer.

Fecal bacterial activity in symptomatic carbohydrate malabsorption: effect on the fecal short-chain fatty acid ratio

BACKGROUND

It is still not clear why only some patients with carbohydrate malabsorption experience symptoms. In a previous study on healthy fructose malabsorbers an increased degradation of fructose in anaerobic fecal cultures from symptomatic malabsorbers was found, indicating increased bacterial activity. In the present study, the same investigation was repeated in patients with nonspecific abdominal complaints and fructose malabsorption. Moreover fecal short-chain fatty acids (SCFA), products of colonic bacterial fermentation of carbohydrates were measured.

PATIENTS AND METHODS

A standard quantity of fructose (500 mg) was added to anaerobic fecal cultures from 25 patients (nine men, 16 women; median of age 53 years, range 36-69 years). The fructose degradation rate was assessed using photometry, and interpreted as representing bacterial activity in the colon. In 14 of the patients, SCFA levels were also measured using chromatography on a capillary column.

RESULTS

10 of the 25 patients had a history of symptoms after ingesting fructose-containing foods, and also showed symptoms during the test; 6 patients had symptoms either in their history or during the test; and the remaining 9 were free of symptoms. There were no differences in the H2 increase. The fructose degradation rate was higher in symptomatic malabsorbers (255 mg vs. 217 mg), but the difference was not significant. However, there was a strong inverse correlation between this bacterial activity and the acetate level, with r = -0.822 (P = 0.000) and r = -0.868 (P = 0.000) in the rank correlation. The correlation for propionate was r = 0.479 (P = 0.083), and that for butyrate was r = 0.599 (P = 0.024).

CONCLUSIONS

This study failed to confirm a significant correlation between fecal bacterial activity and the occurrence of symptoms in patients with fructose malabsorption. However, the interesting correlation with the SCFA raises questions regarding possible connections between colonic bacteria, carbohydrate malabsorption, and the beneficial effect of this pattern of SCFA in several colonic diseases.

Influence of stent design on 1-year outcome after coronary stent placement: a randomized comparison of five stent types in 1,147 unselected patients

The objective of this randomized trial was to assess whether differences in stent design are translated in different clinical outcomes in patients undergoing coronary stent placement. This multicenter randomized trial included 1,147 patients who were randomly assigned to receive one of five types of stainless steel stents: Inflow, MULTI-LINK, NIR, Palmaz-Schatz, and PURA-A stent. Primary endpoint of the study was event-free survival at 1 year. Event-free survival at 1 year was significantly different between the groups (P = 0.014), ranging from 69.4% to 82.4%. Similarly, freedom from myocardial infarction was also significantly different (P = 0.022), with values between 88.2% and 95.2%. Diameter stenosis at 6 months varied from 38.1% +/- 25.0% to 45.6% +/- 27.7% (P = 0. 046), late lumen loss ranged from 1.01 +/- 0.70 mm to 1.20 +/- 0.82 mm (P = 0.085), and the incidence of restenosis varied between 25.3% and 35.9% (P = 0.145). Thus, stent design has a significant impact on the long-term results after coronary stent placement.

Postpartum curettage in patients with HELLP-syndrome does not result in accelerated recovery

OBJECTIVE

Our purpose was to examine the impact of immediate postpartum curettage on the recovery of patients with HELLP-syndrome (hemolysis, elevated liver enzymes, and low platelets).

SUBJECTS

Between January 1994 and July 1997 all patients who presented with HELLP-syndrome in our institution underwent immediate postpartum curettage (n=24). Their outcome was compared with the recovery of women with HELLP-syndrome who were delivered without postpartum curettage between 1987 and 1993 (n=20). Clinical and laboratory data were analyzed.

RESULTS

No significant difference could be found between both groups in terms of normalization of serum glutamic-oxaloacetic transaminase (GOT), serum glutamic-pyruvic transaminase (GPT), lactic dehydrogenase (LDH), and quantitative platelet count. Postpartum hospitalization time was identical in both groups.

CONCLUSION

In our retrospective study no benefit is achieved by immediate postpartum curettage in patients with HELLP-syndrome. In order to eliminate the possible bias of retrospective analysis, we now plan a randomized study to further investigate the impact of immediate postpartum curettage.

Endovascular irradiation from beta-particle-emitting gold stents results in increased neointima formation in a porcine restenosis model

BACKGROUND

Recent studies have shown that ionizing radiation reduces neointima formation after balloon angioplasty and stent implantation in experimental models of restenosis and first clinical trials. The objective of this study was to determine the dose distribution of a new beta-particle-emitting radioactive gold stent and to evaluate the dose-dependent vascular response in the coronary overstretch pig model.

METHODS AND RESULTS

Sixteen Göttinger minipigs underwent placement of 11 nonradioactive and 36 beta-particle-emitting stents with activity levels of 10.4+/-0.6, 14.9+/-2.4, 22.8+/-1.3, 35.8+/-2. 8, and 55.4+/-5.3 microCi of (198)Au. Three months after implantation, the percent area stenosis, neointimal thickness, neointimal area, and vessel injury were analyzed by quantitative histomorphometry. The lifetime radiation doses at a depth of 1 mm were 3.3+/-0.2, 4.7+/-0.5, 7.2+/-0.4, 11.4+/-0.9, and 17.6+/-1.7 Gy for the different activity groups. No dose-response relationship was observed in the radioactive stents with respect to percent area stenosis (P=0.297), mean neointimal thickness (P=0.82), or mean neointimal area (P=0.65). Significantly lower neointima formation and less luminal narrowing was seen in the control group than in the beta-particle-emitting stents (P<0.001). Multilinear regression analysis revealed that only radioactivity made a significant independent contribution to the degree of percent area stenosis (P<0. 001).

CONCLUSIONS

Neointima formation in pigs is markedly increased by beta-particle-emitting stents with (198)Au as the radioisotope. This study provides evidence that dosages of 3 to 18 Gy of low-dose-rate beta-particle irradiation via endovascular stents cause pronounced luminal narrowing in the animal model at 3 months.

Combined transvaginal B-mode and color Doppler sonography for differential diagnosis of ovarian tumors: results of a multivariate logistic regression analysis

OBJECTIVE

Transvaginal sonography is limited in its ability to assess early stage cancers of the ovary as well as in distinguishing benign processes. As a method for characterization of tumor vascularization, color-coded Doppler sonography may be able to improve the diagnostic accuracy of B-mode sonography.

METHODS

Preoperative transvaginal B-mode and Doppler sonography was performed in 63 patients with unclear adnexal lesions prior to operation. Using multiple logistic regression, the independent variables of each procedure were selected and combined to yield a diagnostic flow chart. The diagnostic accuracy of this decision matrix was tested on 257 patients with unclear adnexal tumors.

RESULTS

In the 63 adnexal tumors investigated, the diagnostic impact of isolated sonomorphological assessment with evidence of a "solid area" was 78%. Using Doppler sonography, the best discrimination was achieved by displaying the vascular distribution ("central vascularization"). Combining these independent significant variables of the two procedures raised the diagnostic accuracy to 90% (sensitivity 86%, specificity 93%). The validity achieved by this combination was confirmed by the independent application of this method to the 257 adnexal tumors with unclear malignancy status (diagnostic accuracy 93%, sensitivity 92%, specificity 94%).

CONCLUSIONS

The combination of sonography and Doppler sonography achieves high and reproducible diagnostic accuracy in preoperative malignancy status assessment of adnexal tumors. The additional use of Doppler sonography can thus provide significant aid both for differential diagnostics of adnexal lesions and for the choice of surgical route in the case of an existing indication for operative therapy.

Nonparametric analysis of dose-response relationships

A nonparametric method, isotonic regression, is proposed for analyzing a dose-response relationship and for assessing a threshold value. There are several advantages of this method compared to parametric models. No specific form of the relationship (type of model and use of the covariates) is required. The only assumption is monotonicity. Rejection of specific hypothesis can be based on the result of a permutation test. Several applications (para-aramid, crystalline silica, and PNOC) are presented. In these examples the dose-response relationships are analyzed. Where a relationship is present the existence of a threshold is investigated.

Identifying and modelling prognostic factors with censored data

A major issue in the analysis of diseases is the identification and assessment of prognostic factors relevant to the development of the illness. Statistical analyses within the proportional hazards framework suffer from a lack of flexibility due to stringent model assumptions such as additivity and time-constancy of effects. In this paper we use tree-based models and varying coefficient models to allow for detectability of prognostic factors with possibly non-additive, non-linear and time-varying impact on disease development. Questions concerning model and smoothing parameter selection are addressed. An analysis of a data set of breast cancer patients demonstrates the ability of these methods to reveal additional insight into the disease influencing mechanisms.

Reduced levels of coagulation factor XIII in patients with advanced tumor disease

BACKGROUND/AIMS

Coagulation factor XIII, which induces the stabilization of fibrin the final step in the coagulation cascade, has various physiological effects. Among these, its beneficial effect in gastrointestinal bleeding episodes is well known. With the exception of inflammatory bowel disease, however, few data are available about this effect, particularly with regard to its role in diffuse bleeding in tumor patients. The study was designed to carry out prospective follow-up investigations, gathering data concerning factor XIII levels in patients with advanced gastrointestinal tumors and evaluating the course of the disease as well as the incidence of bleeding.

METHODOLOGY

Sixty patients (22 women, 38 men; median age: 60; range: 29-79) with advanced gastrointestinal tumors were followed-up prospectively. Factor XIII levels were measured using chromogenic substrate. The correlation between the FXIII level and the patients' survival was analyzed using the Cox model.

RESULTS

Factor XIII deficiency (below 70%) was seen in only 7 patients (11.6%), 6 of whom died within a median of 1.5 months after the measurement. In all patients however, there was a significant correlation (P = 0.0133) between FXIII levels and the risk of death. Four bleeding episodes occurred in 3 patients, three times with FXIII levels being below the lower normal range. When substitution was attempted, it was only successful in 1 patient in whom the FXIII level was reduced.

CONCLUSIONS

FXIII may have predictive value as a marker for the prognosis in these patients with advanced tumor disease. Bleeding episodes were rarely seen, but when they do occur they may be associated with reduced levels of FXIII, and substitution may be beneficial as an adjunct or even as the sole therapeutic intervention.

Risk-group discrimination in node-negative breast cancer using invasion and proliferation markers: 6-year median follow-up

Factors reflecting two major aspects of tumour biology, invasion (urokinase-type plasminogen activator (uPA), plasminogen activator inhibiter (PAI-1), cathepsin D) and proliferation (S-phase fraction (SPF), Ki-67, p53, HER-2/neu), were assessed in 125 node-negative breast cancer patients without adjuvant systemic therapy. Median follow-up time was 76 months. Antigen levels of uPA, PAI-1 and cathepsin D were immunoenzymatically determined in tumour tissue extracts. SPF and ploidy were determined flow-cytometrically, Ki"'-67, p53, and HER-2/neu immunohistochemically in adjacent paraffin sections. Their prognostic impact on disease-free (DFS) and overall survival (OS) was compared to that of traditional factors (tumour size, grading, hormone receptor status). Univariate analysis determined PAI-1 (P < 0.001), uPA (P = 0.008), cathepsin D (P = 0.004) and SPF (P = 0.023) as significant for DFS. All other factors failed to be of significant prognostic value. In a Cox model, only PAI-1 was significant for DFS (P < 0.001, relative risk (RR) 6.2). In CART analysis for DFS, the combination of PAI-1 and uPA gave the best risk group discrimination. For OS, PAI-1, cathepsin D, tumour size and ploidy were statistically significant in univariate, but PAI-1 was the only independently significant factor in Cox analysis (P < 0.001, RR 8.9). In particular, this analysis shows that PAI-1 is still a strong and independent prognostic factor in node-negative breast cancer after extended 6-year median follow-up.

Heart-rate turbulence after ventricular premature beats as a predictor of mortality after acute myocardial infarction

BACKGROUND

Identification of high-risk patients after acute myocardial infarction is essential for successful prophylactic therapy. The predictive accuracy of currently used risk predictors is modest even when several factors are combined. Thus, establishment of a new powerful method for risk prediction independent of the available stratifiers is of considerable practical value.

METHODS

The study investigated fluctuations of sinus-rhythm cycle length after a single ventricular premature beat recorded in Holter electrocardiograms, and characterised the fluctuations (termed heart-rate turbulence) by two numerical parameters, termed turbulence onset and slope. The method was developed on a population of 100 patients with coronary heart disease and blindly applied to the population of the Multicentre Post-Infarction Program (MPIP; 577 survivors of acute infarction, 75 deaths during a median follow-up of 22 months) and to the placebo population of the European Myocardial Amiodarone Trial (EMIAT; 614 survivors of acute myocardial infarction, 87 deaths during median follow-up of 21 months). Multivariate risk stratification was done with the new parameters and conventional risk factors.

FINDINGS

One of the new parameters (turbulence slope) was the most powerful stratifier of follow-up mortality in EMIAT and the second most powerful stratifier in MPIP: MPIP risk ratio 3.5 (95% CI 2.2-5.5, p<0.0001), EMIAT risk ratio 2.7 (1.8-4.2, p<0.0001). In the multivariate analysis, low left-ventricular ejection fraction and turbulence slope were the only independent variables for mortality prediction in MPIP (p<0.001), whereas in EMIAT, five variables were independent mortality predictors: abnormal turbulence onset, abnormal turbulence slope, history of previous infarction, low left-ventricular ejection fraction, and high mean heart rate (p<0.001). In both MPIP and EMIAT, the combination of abnormal onset and slope was the most powerful multivariate risk stratifier: MPIP risk ratio 3.2 (1.7-6.0, p<0.0001), EMIAT risk ratio 3.2 (1.8-5.6, p<0.0001).

INTERPRETATION

The absence of the heart rate turbulence after ventricular premature beats is a very potent postinfarction risk stratifier that is independent of other known risk factors and which is stronger than other presently available risk predictors.

Prognostic significance of urokinase (uPA) and its inhibitor PAI-1 for survival in advanced ovarian carcinoma stage FIGO IIIc

Strong evidence has accumulated on the prognostic value of tumour-associated proteolytic factors in patients afflicted with solid malignant tumours, including advanced ovarian cancer. We evaluated the prognostic impact of the protease urokinase plasminogen activator (uPA) and its inhibitor PAI-1 on overall survival in patients with advanced ovarian cancer stage FIGO IIIc in order to select patients at risk. uPA and PAI-1 antigen were determined by ELISA in primary tumour tissue extracts of 86 ovarian cancer patients FIGO stage IIIc enrolled in a prospective study. Univariate and multivariate analyses were performed using the Cox proportional hazard model. The time-varying coefficient model of Gray was used to assess the time-dependent strength of prognostic factors tumour mass, uPA and PAI-1 on overall survival. In all patients, uPA and PAI-1 (optimized cut-offs of 2.0 and 27.5 ng mg(-1) protein respectively), in addition to the traditional prognostic parameters of residual tumour mass, nodal status, grading and ascites volume, were of prognostic significance in univariate analysis for overall survival. Even in patients with residual tumour mass (n = 43), the statistically independent prognostic impact of PAI-1 persisted, allowing further discrimination between low- and high-risk patients. In multivariate analysis, residual tumour mass (P < 0.001, relative risk (RR) 4.5), PAI-1 (P < 0.001; RR 3.1) and nodal status (P = 0.022, RR 2.6) turned out to be strong, statistically independent prognostic parameters. Evaluation of the time-dependent prognostic impact of residual tumour mass and PAI-1 on overall survival (n = 86, 50 months) revealed that the prognostic power of these factors increased with time. In patients with advanced ovarian cancer, both residual tumour mass and PAI-1 are statistically independent strong prognostic factors. Even within patient subgroups with or without residual tumour mass, PAI-1 allowed selection of patients at risk who might benefit from individualized therapy protocols.

HER-2/neu gene amplification by fluorescence in situ hybridization allows risk-group assessment in node-negative breast cancer

In a collective of 112 node-negative breast cancer patients, we compared the prognostic impact of HER-2/neu gene amplification (AMP) determined by fluorescence in situ hybridization (FISH) and HER-2/neu protein overexpression (EXP) measured by immunohistochemistry (IHC) with traditional prognostic factors (tumor size, grade, steroid hormone receptor status, menopausal status) and tumor invasion markers uPA (urokinase-type plasminogen activator) and its inhibitor PAI-1 determined by enzyme immunoassay (ELISA). Median follow-up in patients still alive at time of analysis was 7 years. Automated FISH and IHC were performed on parallel-cut formalin-fixed paraffin-embedded tissue sections. HER-2/neu AMP was detected by FISH in 31% and HER-2/neu EXP was measured by IHC in 41% of the cases. In 13% of the tumors, both AMP and EXP were found. FISH and IHC results were concordant in 56% of all analyzed cases. In univariate analysis, HER-2/neu AMP significantly predicted both disease-free (DFS) and overall survival (OS). HER-2/neu EXP was significant for OS, only. In multivariate analysis of all analyzed prognostic factors, HER-2/neu AMP was the only independent predictive factor for both DFS and OS. CART analysis revealed that HER-2/neu AMP together with the combination uPA/PAI-1 allowed optimal risk-group assessment after a 7-year median follow-up: patients with low levels of both uPA and PAI-1 and no HER-2/neu AMP had a significantly lower relapse rate (4.6%) than the remaining patients (32%). In conclusion, HER-2/neu gene AMP determined by FISH allowed a more accurate risk-group assessment than HER-2/neu protein EXP measured by IHC. Combining the HER-2/neu gene status measured by FISH with levels of tumor invasion markers uPA and PAI-1 improves clinically relevant risk-group assessment. In addition to its prognostic strength, the significant impact of HER-2/neu AMP on OS may reflect its ability to predict resistance to systemic therapy.

Silica dust and lung cancer in the German stone, quarrying, and ceramics industries: results of a case-control study

BACKGROUND

A work force based case-control study of lung cancer was performed in non-silicotic subjects exposed to crystalline silica to investigate the association between silica dust and lung cancer excluding the influence of silicosis.

METHODS

Two hundred and forty seven patients with lung cancer and 795 control subjects were enrolled, all of whom had been employed in the German stone, quarrying, or ceramics industries. Smoking was used as a matching criterion. Exposure to silica was quantified by measurements, if available, or otherwise by industrial hygienists. Several indices (peak, average and cumulative exposure) were used to analyse the relationship between the level of exposure and risk of lung cancer as odds ratios (OR).

RESULTS

The risk of lung cancer is associated with the year of and age at first exposure to silica, duration of exposure, and latency. All odds ratios were adjusted for these factors. Considering the peak exposure, the OR for workers exposed to high levels (>/=0.15 mg/m3 respirable silica dust which is the current occupational threshold value for Germany) compared with those exposed to low levels (<0.15 mg/m3) was 0.85 (95% CI 0.58 to 1. 25). For the time weighted average exposure the OR was 0.91 (95% CI 0.57 to 1.46). The OR for the cumulative exposure was 1.02 (95% CI 0. 67 to 1.55). No increase in risk was evident with increasing exposure.

CONCLUSIONS

This study shows no association between exposure to crystalline silica and lung cancer. The exclusion of subjects with silicosis may have led to dilution with respect to the level of exposure and therefore reduced the power to detect a small risk. Alternatively, the risk of getting lung cancer may be restricted to subjects with silicosis and is not directly linked to silica dust.

Invasion marker PAI-1 remains a strong prognostic factor after long-term follow-up both for primary breast cancer and following first relapse

In 1991, our group was the first to report the prognostic strength of plasminogen activator inhibitor type 1 (PAI-1) in primary breast cancer. The prognostic impact of invasion markers PAI-1 and urokinase-type plasminogen activator (uPA) on disease-free survival (DFS) and overall survival (OS) in breast cancer has since been independently confirmed. We now report on the prognostic impact of PAI-1 and uPA after long-term median follow-up of 77 months for our cohort (n = 316). Levels of uPA, PAI-1, and cathepsin D were determined in tumor tissue extracts by immunoenzymatic methods. S-phase fraction (SPF) was measured flowcytometrically in paraffin sections. Using log-rank statistics, optimized cutoffs were found for PAI-1 (14 ng/mg), uPA (3 ng/mg), cathepsin D (41 pmol/mg), and SPF (6%). In all patients, various factors (PAI-1, uPA, nodal status, SPF, cathepsin D, grading, tumor size, hormone receptor status) showed significant univariate impact on DFS. In Cox analysis, only nodal status (p < 0.001, RR: 3.1) and PAI-1 (p < 0.001, RR: 2.7) remained significant. In node-negative patients (n = 147), PAI-1, uPA, and SPF had significant univariate impact on DFS, whereas in Cox analysis, only PAI-1 was significant. PAI-1 was also significant for DFS within subgroups defined by established factors. In CART analysis, uPA enhanced the prognostic value of PAT-1 and nodal status for determination of a very-low-risk subgroup. For OS, only lymph node status and PAI-1 were significant in multivariate analysis. PAI-1 levels in the primary tumor were also a significant prognostic marker for survival after first relapse in both univariate and multivariate analysis.

Renal cell cancer correlated with occupational exposure to trichloroethene

A previous cohort-study in a cardboard factory demonstrated that high and prolonged occupational exposure to trichloroethene (C2HCl3) is associated with an increased incidence of renal cell cancer. The present hospital-based case/control study investigates occupational exposure in 58 patients with renal cell cancer with special emphasis on C2HCl3 and the structurally and toxicologically closely related compound tetrachloroethene (C2Cl4). A group of 84 patients from the accident wards of three general hospitals in the same area served as controls. Of the 58 cases, 19 had histories of occupational C2HCl3 exposure for at least 2 years and none had been exposed to C2Cl4; of the 84 controls, 5 had been occupationally exposed to C2HCl3 and 2 to C2Cl4. After adjustment for other risk factors, such as age, obesity, high blood pressure, smoking and chronic intake of diuretics, the study demonstrates an association of renal cell cancer with long-term exposure to C2HCl3 (odds ratio 10.80; 95% CI: 3.36-34.75).

Disease-adapted relapse therapy for ovarian cancer: results of a prospective study

Primary therapy of advanced ovarian cancer is standardized, the therapy in relapsed ovarian cancer however is still controversial. In a prospective study the benefit of secondary surgery and/or second-line chemotherapy were evaluated. 139 patients with relapsed ovarian cancer were stratified according to a treatment plan: patients with early relapse (recurrence-free interval 12 months) or primary progression during chemotherapy (n=43) were treated chemotherapeutically with etoposide (p.o. vs. i.v.). Patients with late relapse (recurrence-free interval >12 months, n=96) were referred, if possible, to a secondary debulking operation, followed by a platinum-based chemotherapy. Remission-rate, toxicity and survival time were analyzed. Median survival time in the <early relapse> group was 15 months compared to 30 months in patients with late relapse (p=0.0004). Within the <late relapse> group patients with secondary debulking and chemotherapy (n=59) had a statistically significant survival advantage compared to patients who had only chemotherapy (n=37) (38 vs. 12 months, p<0.0001). The unfavorable group of patients with early relapse should be treated chemotherapeutically, whereas in patients with late relapse a secondary debulking seems to improve prognosis.

Long-term results of endoscopic treatment of biliary duct obstruction due to pancreatic disease

BACKGROUND/AIMS

Endoscopic stenting has become an established method of providing palliative treatment in cases of malignant biliary obstruction, as well as in benign biliary stenosis. Several problems associated with the types of stent used have not yet been resolved, and an ideal stent has yet to be designed. Observation of the clinical course for patients with biliary obstruction of various etiologies, and evaluation of the results with various treatment methods are the aims of this study.

METHODOLOGY

In 1993 and 1994, biliary obstruction was treated endoscopically in 47 patients with a malignant pancreatic tumor and in 18 patients with chronic pancreatitis. The primary intervention was assessed retrospectively on the basis of the patients' records, and information concerning the clinical course was obtained by contacting the patients or their relatives or general practitioners.

RESULTS

Primary endoscopic drainage was successful in all cases. Only one of the patients with pancreatic tumors is still alive; survival after stent placement averaged 6.2 months. Metal stents remained patent significantly longer than plastic stents and percutaneous transhepatic biliary drains (PTBDs)(8.2 versus 3.5 or 1.9 months; p < 0.001). In cases of chronic pancreatitis, three of the nine patients who received only endoscopic treatment, without stenting, were able to continue without stents in the longer term, whereas seven of the nine who underwent surgery had no further problems.

CONCLUSIONS

Endoscopic drainage of biliary obstruction provides excellent short-term results. In long-term treatment for purely palliative purposes, metal stents remain patent for longer than plastic stents. In chronic pancreatitis, surgical treatment clearly seems to provide better long-term results than endoscopic therapy.

Prognostic impact of tumor biological factors on survival in node-negative breast cancer

Tumor biological factors uPA, PAI-1, cathepsin D, S-phase fraction (SPF), MIB1 (Ki-67), p53, and HER-2/neu were assessed in 100 node-negative breast cancer patients. Their prognostic impact on disease-free (DFS) as well as overall survival (OS) was compared to that of traditional factors tumor size, grading, and steroid hormone receptor status. Antigen levels of uPA, its inhibitor PAI-1, and cathepsin D were determined in tumor tissue extracts by immunoenzymatic methods. SPF was determined by flow cytofluorometry, MIB1, p53, and HER-2/neu by immunohistochemistry in adjacent routinely formalin-fixed paraffin sections. Median follow-up in all patients still alive at time of analysis was 76 months. Univariate analysis determined PAI-1 (p = 0.0001), uPA (p = 0.0437), MIB1 (p = 0.0214), and SPF (p = 0.0248) as statistically significant prognostic factors for DFS. In contrast, tumor size, steroid hormone receptor status, grading, p53, HER-2/neu, and cathepsin. D failed to be of prognostic value. In multivariate analysis, including the statistically significant prognostic factors PAI-1, uPA, MIB1, and SPF, only PAI-1 (p = 0.0003, relative risk: 4.7) proved to be of independent statistical significance for DFS. Regarding OS, PAI-1 was the only statistically significant prognostic factor in univariate (p = 0.0001) as well as multivariate analysis (p = 0.0000, relative risk: 7.1). Thus, factors describing the invasive and metastatic capacity of tumor cells (uPA, PAI-1) and factors related to their proliferative activity (SPF, MIB1) provide valuable prognostic information in node-negative breast cancer patients.

Identification of low-risk node-negative breast cancer patients by tumor biological factors PAI-1 and cathepsin L

In node-negative breast cancer, 70% of patients are cured by surgery alone and thus should be spared the necessity of systemic adjuvant treatment. Histomorphological and tumor biological prognostic factors may be employed to assess the patient's risk profile with regard to disease recurrence and death. To evaluate the relationship between tumor biological factors and the metastatic potential of primary breast cancer, proteolytic factors uPA, PAI-1, and cathepsin L, which are associated with tumor invasion and metastasis, were determined in breast cancer tissue extracts by ELISA and the values assessed by uni- and multivariate analysis as well as CART (classification and regression trees) in comparison with traditional prognostic factors. Cysteine protease cathepsin L, serine protease uPA, and the protease inhibitor PAI-1 were determined by ELISA in extracts of primary tumors of 103 node-negative breast cancer patients and values assessed by univariate and multivariate analysis in comparison with traditional prognostic factors (tumor size, steroid hormone receptor status, grading, vessel invasion, menopausal status). Median follow-up of patients still alive at time of follow-up was 56.5 months (range 34-88). PAI-1, cathepsin L, tumor size, grading, and steroid hormone receptor status but not uPA, vessel invasion, and menopausal status were of prognostic relevance for disease-free survival (univariate analysis). Multivariate analysis of disease-free survival (Cox proportional hazards model) disclosed PAI-1 (relative risk of 8.6, p = 0.0001) to be the only strong and statistically independent prognostic factor. By CART-analysis, however, the combination of PAI-1 (< or = 14 ng/mg protein) and cathepsin L (< or = 1,100 ng/mg protein) allowed the identification of a subgroup comprising 68% of the node-negative breast cancer patients having a very low risk of disease recurrence (2/70; incidence of 0.8% per year) versus the high-risk group with PAI-1 (> 14 ng/mg protein) and cathepsin L (> 1,100 ng/mg protein) showing an increased recurrence rate (14/33; incidence of 8.6% per year). We conclude that by the combined determination of PAI-1 and cathepsin L tumor levels low-risk node-negative breast cancer patients may be identified. These patients most probably will not benefit from systemic adjuvant therapy.

Bimodal distribution of angiographic measures of restenosis six months after coronary stent placement

BACKGROUND

Restenosis has been perceived as the tail end of a normal distribution of the response of the vessel to the intervention. However, recent studies have described a bimodal distribution for de novo lesions after percutaneous transluminal coronary angioplasty. This finding suggests that some lesions may be more susceptible for restenosis. Whether this holds true for a wider spectrum of lesions undergoing stent placement is not yet known. The present study analyzes the frequency distribution of angiographic indexes of restenosis 6 months after coronary stent implantation.

METHODS AND RESULTS

Quantitative angiographic evaluation was performed in 1084 lesions of 1084 patients before, immediately after, and 6 months after successful Palmaz-Schatz stent placement; this represented 80.4% of patients eligible for follow-up angiography. Principal end points of the analysis were angiographic indexes of restenosis at 6 months. Twenty-two lesions that became totally occluded at follow-up were excluded from most parts of the analysis. Diameter stenosis, minimal luminal diameter (MLD), and lumen loss at 6 months did not follow a normal pattern; the bimodal pattern was demonstrated through deconvolution that yielded two separate normal components delineating two lesion populations, which developed distinctively different degrees of lumen renarrowing. The first and larger subgroup of lesions, which was less prone to restenosis, was centered around a mean value of 27% for diameter stenosis and 2.19 mm for MLD, whereas the second subgroup, with a greater tendency for restenosis, was situated around a mean value of 68% for diameter stenosis and 0.76 mm for MLD. The intersection point between the two theoretical normal distribution components was 53.5% for diameter stenosis and 1.09 mm for MLD at follow-up.

CONCLUSIONS

Frequency-distribution curves of angiographic indexes of restenosis after coronary stent placement have a bimodal pattern, suggesting the existence of two distinct populations with different propensity to restenosis. These findings may encourage future efforts for the timely identification of the subset with a higher risk as the target of specific antirestenotic strategies.

Electrophysiological investigation of central, peripheral and autonomic nerve function in workers with long-term low-level exposure to carbon disulphide in the viscose industry

OBJECTIVE

Neurotoxicity of carbon disulphide (CS2) is well known. The air concentration at the workplace at which such adverse effects can first be observed is the subject of controversial discussion.

METHODS

In a cross-sectional study on CS2-exposed workers peripheral motor and sensory nerve conduction studies, somatosensory evoked potentials, thermotesting and investigation of forced respiration sinus arrythmia have been carried out. The data from 222 workers exposed to CS2 in the viscose industry were evaluated and compared with data from 191 employees from the same factory with similar physical and psychological stress factors but without detectable occupational contact to neurotoxic substances. Median exposure to CS2 was below the currently valid occupational-medical threshold limit value (MAK-value) of 10 ppm. Multiple linear or multiple logistic regression analysis was used to check for statistical differences.

RESULTS

Binary evaluation (comparison of exposed persons versus controls after multiple linear regression) revealed a slightly lower value in the exposed group for the motor nerve conduction velocity (MNCV, -0.76 m/s, median 48 m/s), but a long way from pathological thresholds. No dose-response relationship could be found within the exposed group for any evaluation criteria of CS2-exposure. Somatosensory evoked potentials, thermotesting and analysis of heart rate variability yielded no indication of a neurotoxic effect of CS2.

CONCLUSION

Isolated decrease of MNCV in binary evaluation is, with regard to the known mechanism of CS2-neurotoxicity and the lack of a dose-response relationship, obviously not due to toxic effects. We interpret our results as showing that an adverse effect of carbon disulphide at the exposure ranges found was not detectable in the exposed group.

Restenosis after coronary stent placement and randomization to a 4-week combined antiplatelet or anticoagulant therapy: six-month angiographic follow-up of the Intracoronary Stenting and Antithrombotic Regimen (ISAR) Trial

BACKGROUND

Platelets and mural thrombus at the lesion site may play a key role in initiating the restenosis process after coronary interventions. The ISAR Trial provides a comparison of the outcomes of patients randomized to two different antithrombotic regimens administered for 4 weeks after successful coronary stent placement: combined antiplatelet therapy (aspirin plus ticlopidine) or a conventional anticoagulant regimen (phenprocoumon with initial overlapping heparin plus aspirin). Within the first 4 weeks after stent placement, combined antiplatelet therapy has been associated with a significant reduction of ischemic complications. In the present study, we examined whether combined antiplatelet therapy administered for 4 weeks after stent placement is able to reduce the process of restenosis at 6 months.

METHODS AND RESULTS

Of 517 patients initially randomized, 496 were eligible for 6-month angiographic follow-up. Scheduled angiography was performed in 432 of the eligible patients (87.1%), 216 in each group. In a comparison of the two groups, there were no significant differences in clinical and procedural variables or in qualitative and quantitative lesion characteristics before and after stenting. At 6 months, minimal luminal diameter was 1.95+/-0.86 mm in the group with initial combined antiplatelet therapy and 1.90+/-0.87 mm in the group with initial anticoagulant therapy (P=.55). Late lumen loss was 1.10+/-0.81 and 1.15+/-0.75 mm (P=.54), and the restenosis rate was 26.8% and 28.9%, respectively (P=.70). Target lesion revascularization rate was 14.6% in the antiplatelet therapy group and 15.6% in the anticoagulant therapy group (P=.85).

CONCLUSIONS

This study shows that combined antiplatelet therapy (aspirin plus ticlopidine) administered for 4 weeks after coronary Palmaz-Schatz stent placement does not result in a detectable benefit for the prevention of restenosis compared with conventional anticoagulant therapy (phenprocoumon with initial overlapping heparin plus aspirin).