Friedrich Wrba

Forceps Biopsy and Brush Cytology during Endoscopic Retrograde Cholangiopancreatography for the Diagnosis of Biliary Stenoses

BACKGROUND For evaluating pancreaticobiliary stenoses during endoscopic retrograde cholangiopancreatography (ERCP) tissue sampling techniques may be important. Brush cytology and forceps biopsy during ERCP are two potential, but so far only incompletely evaluated, tools for the diagnosis of malignant biliary or pancreatic stenoses. METHODS Between 1992 and 1995 we acquired 133 cytologic and/or histologic samples from 119 patients who underwent ERCP because of biliary duct stenoses. Sixteen patients had to be excluded from the study due to insufficient follow-up information. After papillotomy, brush cytology was performed in 65 cases (63 patients), and forceps biopsy in 119 cases (106 patients under fluoroscopic guidance. Both methods were applied in combination 51 times (48 patients). The nature of the stenoses was confirmed by surgery, autopsy, or by the subsequent clinical course. RESULTS The sensitivity was 46.7% for brush cytology and 64.9% for forceps biopsy. The combined application of both methods resulted in superior sensitivity (70.4%). Specificity was 100% for all methods. CONCLUSIONS These numbers lead us to recommend a combined and more frequent application of brush cytology and forceps biopsy of bile duct stenoses to enhance the diagnostic yield whenever substantial influence on therapy can be expected.

Subclinical impairment of brain function in chronic hepatitis C infection.

BACKGROUND/AIMS Central nervous system abnormalities such as fatigue and depression occur more frequently in chronic hepatitis C virus (HCV) infection than in many other causes of chronic liver disease. The finding that fatigue is unrelated to activity of hepatitis or mode of infection could indicate an independent effect of HCV on brain function. This study tested the hypothesis of a subclinical cognitive dysfunction in HCV-infected patients. METHODS One-hundred untreated HCV-RNA positive biopsy-proven patients were investigated by P300 event-related potentials, a sensitive electrophysiologic test of cognitive processing. Health-related quality of life and fatigue were assessed using the SF-36 questionnaire and the Fatigue Impact Scale, respectively. RESULTS Cognitive brain function was subclinically impaired in the cohort of HCV-infected patients as indicated by significantly prolonged P300 latencies (P=0.01 for comparison to matched healthy subjects) and reduced P300 amplitudes (P<0.001, respectively). Seventeen of the 100 HCV-infected patients had P300 latencies outside the age-adjusted normal range. Abnormal P300 characteristics were not related to the degree of histologic or biochemical activity of hepatitis, severity of fatigue or mental health impairment. CONCLUSIONS This study demonstrates that patients with HCV infection showed a slight but significant neurocognitive impairment, possibly indicating a further extrahepatic manifestation of chronic hepatitis C.

Association between Helicobacter pylori Infection and Pancreatic Cancer

Purpose: In order to determine whether infection with Helicobacter pylori might be associated with pancreatic adenocarcinoma, we performed a study to compare the H. pylori seroprevalence rate between patients with pancreatic carcinoma and matched control subjects. Patients and Methods: Blood samples from 92 patients with histologically confirmed diagnosis of pancreatic adenocarcinoma admitted to our hospital between January 1994 and July 1995 were analyzed for the presence of IgG antibodies against H. pylori by a commercially available enzyme-linked immunosorbent assay. Thirty patients with gastric cancer, 35 patients with colorectal cancer, and 27 healthy volunteers served as controls. In addition to these serological analyses, tumor specimens from 20 patients with pancreatic adenocarcinoma were microscopically investigated for the presence of H. pylori. Results: 65% of pancreatic cancer patients and 69% of those with gastric cancer were found to be seropositive, while only 45% of the other controls tested positive. Statistical analysis revealed no difference in seropositivity between the cohort of patients suffering from pancreatic and gastric cancer. The rate of seropositivity was more prominent, however, in pancreatic cancer patients when compared with those suffering from colorectal cancer combined with normal controls (p = 0.035), with an odds ratio of 2.1 (1.1–4.1). Microscopic evaluation of human pancreatic cancer specimens showed no evidence for the presence of H. pylori. Conclusion: Our data suggest an association between H. pylori infection and pancreatic cancer. Despite demonstration of a positive relationship and its physiological plausibility, larger prospective studies are needed to confirm our preliminary findings and to assess H. pylori as a potential carcinogenic risk factor.

25-Hydroxyvitamin D3-1α-hydroxylase Expression in Normal and Malignant Human Colon

1,25-dihydroxyvitamin D3 has anti-mitotic, pro-differentiating, and pro-apoptotic activity in tumor cells. We demonstrated that the secosteroid can be synthesized and degraded not only in the kidney but also extrarenally in intestinal cells. Evaluation of 1,25-dihydroxyvitamin D3-synthesizing CYP27B1 hydroxylase mRNA (real-time PCR) and protein (immunoblotting, immunofluorescence) showed enhanced expression in high- to medium-differentiated human colon tumors compared with tumor-adjacent normal mucosa or with colon mucosa from non-cancer patients. In high-grade undifferentiated tumor areas expression was lost. Many cells co-expressed CYP27B1 and the vitamin D receptor. We suggest that autocrine/paracrine antimitotic activity of 1,25-dihydroxyvitamin D3 could prevent intestinal tumor formation and progression. (J Histochem Cytochem 52:985–989, 2004)

Immunocytochemical Localization of the Extracellular Calcium-Sensing Receptor in Normal and Malignant Human Large Intestinal Mucosa

SUMMARY We identified the parathyroid type Ca2+-sensing receptor (CaR) in normal human colon mucosa and in cancerous lesions at the mRNA and protein level. Polymerase chain reaction produced an amplification product from reverse-transcribed large intestinal RNA which corresponded in size and length to a 537-bp sequence from exon 7 of the CaR gene. With a specific antiserum against its extracellular domain, the CaR could be detected by immunostaining in normal human colon mucosa in cells preferentially located at the crypt base. The CaR protein was also expressed in tumors of the large bowel in all 20 patients examined. However, the great majority of CaR-positive cells in the adenocarcinomas inspected were confined to more differentiated areas exhibiting glandular-tubular structures. Poorly or undifferentiated regions were either devoid of specific immunoreactivity or contained only isolated CaR-positive cells. In the normal mucosa and in glandular-tubular structures of cancerous lesions, the CaR was exclusively expressed in chromogranin A-positive enteroendocrine cells and in only a small fraction of PCNA-positive cells.

Hepatocellular fat accumulation and low serum cholesterol in patients infected with HCV-3a

OBJECTIVE:The aim of this study was to prospectively investigate the prevalence of hepatic steatosis in chronic hepatitis C patients with respect to viral genotype, hepatic iron concentration, total body iron, body mass index, and serum lipid parameters. Furthermore, the effect of hepatitis C virus (HCV) eradication by antiviral therapy on serum cholesterol levels was studied.METHODS:Hepatocellular fat and hepatic iron were determined in liver biopsies obtained from 137 interferon-naïve patients with chronic hepatitis C (100 men, 37 women, mean age 40.8 ± 10.7 yr) enrolled in two prospective clinical trials of interferon/ribavirin therapy. Body mass index and fasting cholesterol levels were determined at baseline, during, and after therapy.RESULTS:Marked steatosis (>20% of fat-containing hepatocytes) was found in 74.5% of patients infected with HCV-3a compared with 17.9% in HCV-1 and 21.7% in HCV-4-infected patients (p < 0.01). Steatosis in HCV-3a-infected patients did not correlate with the body mass index, hepatic iron content, ferritin, or transferrin saturation. At baseline, serum cholesterol was lower in patients infected with HCV-3a (147 ± 42 mg/dl; p < 0.01) compared with HCV-1 (188 ± 36) or HCV-4 (172 ± 35). In contrast to HCV-1- or HCV-4-infected patients, serum cholesterol increased in HCV-3a virological responders at the end of treatment and 6 months after therapy (baseline 146 ± 38, end of treatment 166 ± 29, p < 0.05, sustained virological response 200 ± 34, p < 0.01). However, serum cholesterol remained unchanged in HCV-3a nonresponders.CONCLUSIONS:Our data suggest that, in addition to inducing steatosis, HCV-3a lowers serum cholesterol. This metabolic effect is fully reversible after successful HCV-3a eradication. This unique property is not shared by other HCV genotypes.

The Role of Non‐Deletional Tolerance Mechanisms in a Murine Model of Mixed Chimerism with Costimulation Blockade

Peripheral and central clonal deletion are important tolerance mechanisms in models using bone marrow transplantation (BMT) with costimulation blockade (CB). However, since tolerance can be found before peripheral deletion is complete and since elimination of recipient CD4+ cells at the time of BMT prevents tolerance induction, we investigated the potential roles of regulation and anergy in such a murine model. We found that transient elimination of CD25+ cells or neutralization of IL2 immediately after BMT and CB prevented the induction of skin graft tolerance. Cotransfer into SCID mice of CD4+ cells taken from chimeras early after BMT, together with naïve recipient‐type CD4+ cells significantly prolonged donor skin graft survival. In contrast, cotransfer of CD4+ cells harvested from chimeras late after BMT did not prolong donor skin graft survival. Besides, depletion of CD25+ cells in established chimeras several months post‐BMT did not break tolerance. In vivo administration of recombinant IL2 inhibited chimerism and tolerance neither early nor late post‐BMT, arguing against a decisive role for classical anergy. Thus, CD4 cell‐mediated regulation contributes significantly to tolerance induction early after BMT, but appears to have no critical role in the maintenance of tolerance.

Primary interferon resistance and treatment response in chronic hepatitis C infection: a pilot study

Summary Only 30% of patients with chronic hepatitis C virus genotype 1 (HCV-1) infection achieve a sustained virological response to interferon and ribavirin combination therapy. We prospectively assessed decline in viral load 24 h after one dose of interferon alfa as a predictor of non-response to 6 months of treatment with interferon and ribavirin. Interferon sensitivity was measured before initiation of combination therapy. We measured viral load in 29 consecutive patients, who had not previously been treated with interferon and who were chronically infected with HCV-1 within 24 h after one dose of 5 MU or 10 MU interferon alfa-2b, and 14 days of daily 5 MU interferon alfa-2b. A 24 h viral load decline by less than 70% of baseline after 5 MU interferon was the best pretreatment measure to identify non-responders (specificity 100%, n=10, 95% CI 74–100], sensitivity 83% [15/18], 59–96]).

TP53 genotype but not p53 immunohistochemical result predicts response to preoperative short-term radiotherapy in rectal cancer.

ObjectiveTo evaluate and compare the predictive power of p53 gene analysis versus p53 immunohistochemical staining in terms of response to preoperative short-term radiotherapy using 25 Gy in operable rectal cancer. Summary Background DataRecent studies show that p53 may be a determinant of radiosensitivity being required for induction of apoptosis in case of radiation-induced DNA damage. MethodsPreirradiation biopsy samples of 64 patients with rectal carcinoma were analyzed. Genetic alterations of the p53 gene were detected by complete direct sequencing of exons 2 to 10. Expression of the nuclear phosphoprotein p53 was assessed by immunohistochemical staining. Results were correlated with histopathology of resected specimens and follow-up data, respectively. ResultsMutations of the p53 gene were present in 45% of tumors. Patients with a normal p53 gene had a significant survival advantage. Comparing pre- and postradiotherapy T category, a reduction was seen in patients with normal p53 genotype only. A mutant p53 genotype was highly specific in indicating stable disease concerning T category after irradiation. Protein overexpression was detected in 61%. Overexpression of the p53 protein was not related to survival or response. The concordance between immunohistochemistry and sequencing was only 0.51. ConclusionsThe authors show that downstaging after short-term radiation may occur but is seen in tumors with normal p53 gene only. Moreover, p53 genotype but not p53 immunohistochemistry is predictive for response to preoperative short-term radiotherapy and patient survival.

Detection of focal hepatic lesions: comparison of unenhanced and SHU 555 A-enhanced MR imaging versus biphasic helical CTAP.

The purpose of this study was to compare the diagnostic sensitivity of unenhanced magnetic resonance (MR) imaging, and MR imaging with a new superparamagnetic iron oxide (SPIO)‐enhanced contrast agent (SHU 555 A) with biphasic helical computed tomography during arterial portography (CTAP) in patients with focal liver lesions. Eighteen patients with a total of 91 (78 malignant, 13 benign) proven liver lesions underwent unenhanced short tau inversion recovery (STIR), T2‐weighted (T2‐w) TSE, and SHU 555 A‐enhanced T2‐w turbo spin‐echo (TSE) MR imaging and biphasic helical CTAP. The standard of reference was histopathologic analysis of resected specimens in 59 lesions, intraoperative ultrasound with biopsy in 20 lesions, and CT‐guided biopsy and follow‐up in 12 lesions. Diagnostic performance of the imaging modalities was compared quantitatively and qualitatively by assessing lesion involvement in liver segments. There were 68 lesions detected on unenhanced T2‐w TSE, which resulted in a sensitivity of 75%. With the STIR sequence, 76 lesions were detected, for a sensitivity of 84%, and with SHU 555 A‐enhanced MRI, 84 lesions were detected, for a sensitivity of 92%. CTAP detected 88 lesions, for a sensitivity of 97%. The accuracy for unenhanced T2‐w TSE was 98%, for STIR 99%, for enhanced‐MRI 100%, and for CTAP 95%. The specificity was 100% for SHU 555 A‐enhanced MRI and 95% for CTAP. SHU 555 A‐enhanced MRI was superior to nonenhanced MRI (P < 0.05) and equivalent to CTAP in terms of sensitivity. Due to the absence of false‐positive results on SHU 555 A‐enhanced MRI, the specificity and accuracy of enhanced MRI were higher than those of CTAP, but the difference was not statistically significant (P = 0.134). J. Magn. Reson. Imaging 2000;11:665–672.