Biomedical subjects

J P Baak

Publications and source records attributed to J P Baak.

At least 19 recordsLinked to original sources

PubMed2001

Prognostic value of morphometry in patients with normal breast tissue or usual ductal hyperplasia of the breast.

Women with usual ductal hyperplasia have a relative risk of 1.6-1.9 of subsequent breast cancer development. This slightly increased risk is generally not considered sufficiently high to justify (chemo)preventive therapy. It is therefore important to identify high-risk ductal hyperplastic lesions that would benefit from such a treatment. Nuclear morphometric features have been shown in previous work to be useful for objectively describing morphologic features associated with high risk in (pre)invasive breast lesions. The aim of this study was to evaluate whether such morphometric features can also predict subsequent invasive cancer development in patients with the common pattern of usual ductal hyperplasia or a normal breast biopsy. The present case-control study included 423 women with normal breast biopsies (n = 89) or biopsies containing usual ductal hyperplasia (n = 334). Of these 423 women, 132 developed invasive breast cancer during follow-up (mean 16.7 +/- 7.0 years). On the original hematoxylin and eosin-stained sections, nuclear morphometry was performed with a digitizing video overlay system, and mitotic and apoptotic indices were assessed. Patients with mean nuclear feature values for area, perimeter, diameter or longest axis above the 75th percentile had 1.6-1.7 times the breast cancer risk of women with mean nuclear feature values below this value. Pairwise combinations of these features yielded slightly higher cancer risks for the fourth quartile patients, with the highest risk (1.9) for patients with SD of nuclear area and perimeter values above the 75th percentile. The number of apoptotic or mitotic cells had no prognostic value for patients with apparently normal tissue or usual ductal hyperplasia. Our results give a first indication that normal breast tissue or usual ductal hyperplasia harbor nuclear morphologic changes that, when assessed by morphometry, may be used to predict breast cancer development. It is worthwhile studying this further in independent groups of patients with long-term follow-up.

Adolescent↗

PubMed2001

Molecular identification of latent precancers in histologically normal endometrium.

Discovery of somatically mutated cells in human tissues has been less frequent than would be predicted by in vitro mutational rates. We analyzed the PTEN tumor suppressor gene as an early marker for endometrial carcinogenesis, and we show that 43% of histologically normal premenopausal endometria contain rare glands that fail to express PTEN protein because of mutation and/or deletion. These persist between menstrual cycles. Histopathology of PTEN-null glands is initially unremarkable, but with progression, they form distinctive high-density clusters. These data are consistent with a progression model in which initial mutation is not rate limiting.

Adult↗

PubMed2001

Ki-67 immunoquantitation in cervical intraepithelial neoplasia (CIN): a sensitive marker for grading.

The aim of this study was to assess the value of Ki-67 immunoquantitation with a computerized image analysis system for grading support in cervical intraepithelial neoplasia (CIN). Sixty-five 'blind' consensus biopsies (23 CIN 1, 22 CIN 2, and 20 CIN 3) were used as a learning set. Measurements were done in the carefully selected most severely dysplastic part of the epithelium of each CIN case. The resulting discriminating combination of quantitative features was then prospectively applied on 121 new biopsies (test set) and compared with the classical CIN grade assessed routinely by six different pathologists and with the blind review grades assessed by two experienced pathologists. In the learning set of 65 cases, a jack-knifed stepwise discriminant analysis showed that the 90th percentile of the stratification index and the number of positive nuclei per 100 microm basal membrane are the best discriminating set of features to distinguish the three CIN grades at the same time. With these features, two CIN 1 cases were 'misclassified' as CIN 2 and nine CIN 2 cases as CIN 3. Overall agreement, therefore, was only 83%. However, recut of the paraffin blocks in the two 'misclassified' CIN 1 cases revealed CIN 2 in the first and CIN 3 in the other, while the other CIN 1 cases that were correctly classified with Ki-67 quantitation remained CIN 1. Likewise, nine CIN 2 cases were misclassified as CIN 3, but in two of these nine cases histological follow-up clearly indicated CIN 3. Agreement may thus be higher than the 83% in the learning set suggests. In the subsequent prospective evaluation on 121 routine CIN cases (test set), agreement between routine CIN grades (by six independent different pathologists) and quantitative Ki-67 classification was 78%. However, when compared with the blind review CIN grades of two expert pathologists, agreement was 97% and sensitivity, specificity, and positive and negative predictive value were very high. It is concluded that Ki-67 immunoquantitation is a useful diagnostic adjunct to distinguish different CIN grades and may also be a sensitive biological indicator of progression of seemingly low-grade CIN.

Antigens, Neoplasm↗

PubMed2001

Nuclear cytometric changes in breast carcinogenesis.

Breast cancer is thought to originate through progressively aberrant precursor lesions, paralleled by increasing morphological changes. The aim of this study was to quantify nuclear features by image cytometry in invasive breast cancer and its early (hyperplasia) and late (ductal carcinoma in situ) precursor lesions, in order to objectively describe nuclear changes in the spectrum of proliferative intraductal and invasive breast lesions. Image cytometry was performed on tissue sections of 20 samples of normal breast tissue, 71 of usual ductal hyperplasia (UDH), nine of atypical ductal hyperplasia (ADH), and 11 of well-differentiated and 13 of poorly differentiated ductal carcinoma in situ (DCIS) lesions. The invasive breast carcinomas consisted of 19 well-differentiated and 24 poorly differentiated lesions. Through the spectrum from normal breast tissue to invasive carcinoma, progressive changes in many nuclear features were measured. Significant differences were found between nuclei of florid ductal hyperplasia compared with mild and moderate ductal hyperplastic lesions, suggesting that florid ductal hyperplasia may be a more advanced lesion than assumed and may contain cancer precursor cells. No differences were found between ADH and well-differentiated DCIS, suggesting that these lesions are closely related. Feature values of well-differentiated DCIS were comparable to values found in well-differentiated invasive carcinoma and the same applied to poorly differentiated DCIS and invasive lesions. These results support the hypothesis that breast cancer develops through different routes of progression, one leading to well-differentiated invasive cancer through well-differentiated DCIS, and one leading to poorly differentiated invasive cancer through poorly differentiated DCIS. In conclusion, image cytometry reveals progressive changes in nuclear morphological and subvisual chromatin distribution features in the spectrum from intraductal proliferations to invasive breast cancer. This provides evidence for a progression from usual to atypical ductal hyperplasia and then to invasive cancer, through different routes for well-differentiated and poorly differentiated lesions.

Breast↗

PubMed2001

Similarity in expression of cell cycle proteins between in situ and invasive ductal breast lesions of same differentiation grade.

There is increasing evidence that there are different progression routes leading to invasive breast cancer, depending on histology and differentiation grade. The aim of this study was to determine alterations in the expression of proteins involved in proliferation and apoptosis in non-invasive and invasive ductal breast lesions. Immunohistochemistry was performed on 106 usual ductal hyperplasias (UDH), 61 DCIS lesions and 53 invasive ductal breast carcinomas. Increased proliferation (Ki67), overexpression of cyclin D1, HER-2/neu, p21 and p53, and decreased expression of bcl-2 and p27 could already be found in UDH. Significant differences between UDH and DCIS lesions were found for only one protein when UDH was compared with well-differentiated DCIS (p27), for three proteins when compared with intermediately differentiated DCIS (p21, cyclin D1, Ki-67), and for all proteins when compared with poorly-differentiated DCIS. Comparing DCIS with invasive lesions of same differentiation grade, proliferation was elevated in the invasive lesions. Altered expression of the other proteins was in general only slightly increased in the invasive lesion compared with DCIS. The number of proteins with altered expression per lesion was highest in poorly-differentiated lesions and was comparable between DCIS and invasive cancer of the same differentiation grade. In conclusion, the biggest changes in expression of these proliferation and apoptosis related proteins appear to occur during the transition from hyperplasia to DCIS; they probably play a minor role in the transition from DCIS to invasive breast lesion of same differentiation grade. Well-differentiated in situ and invasive breast lesions share many of the aberrations in expression of these proteins, as do poorly-differentiated in situ and invasive lesions. However, there are many differences between the well and poorly-differentiated lesions. This further supports the existence of different progression routes leading to breast cancer.

Apoptosis↗

PubMed2001

Relationship between the presence of oncogenic HPV DNA assessed by polymerase chain reaction and Ki-67 immunoquantitative features in cervical intraepithelial neoplasia.

The aims of this study were firstly to determine which Ki-67 immunoquantitative parameters correlate with the presence of oncogenic human papillomavirus (HPV) in cervical intraepithelial neoplasia (CIN) lesions; and secondly to compare prospectively the routinely assessed CIN grades with the Ki-67 quantitative pathological CIN grade, the expert revised grade, and the presence of oncogenic HPV DNA. HPV polymerase chain reaction (PCR) and Ki-67 immunoquantitation were performed on 90 consecutive biopsies (16 CIN 1, 35 CIN 2, and 39 CIN 3). CIN grade was assessed routinely by six different pathologists. The presence of the lesion was confirmed in a histological section following the material used for PCR and Ki-67 analysis. In a second prospective routine test set analysis, 66 more CIN lesions (14 CIN 1, 15 CIN 2, and 37 CIN 3) were routinely graded (also by six different pathologists, routine CIN grade=CIN(ROUT)), studied for oncogenic HPV DNA, and graded by quantitative Ki-67 features (quantitative pathological CIN grade=CIN(QP)). These latter cases were blindly revised by one of the authors (reference CIN grade=CIN(REF)). Eight of the nine Ki-67 immunoquantitative features showed a significant difference between the oncogenic HPV-positive and -negative cases. The best single discriminator was the 90th percentile of the stratification index (SI90). All 61 cases with Ki-67 SI90>0.60 were HPV-positive (68% of the total group studied). Of the 29 cases with SI90< or =0.60, 16 were negative and 13 positive for oncogenic HPV and none of the Ki-67 features (either single or combined) could distinguish them. Using stepwise multivariate analysis, the best discriminating combination of features was SI90 and the percentage of Ki-67-positive nuclei in the deep third layer of the epithelium (PERC DL). The combination of SI90 and the percentage of Ki-67-positive nuclei per 100 microm basal membrane was nearly as strong as that of SI90 and PERC DL. With these two features, 86% of the cases were correctly classified. The subjective estimate of SI90 (>0.60 or < or =0.60) by two independent observers was not accurate and not reproducible. In the prospective routine test set analysis of 66 cases, the 37 CIN(ROUT)=3 all had CIN(QP) and CIN(REF)=3 and all these cases were oncogenic HPV-positive. Eight of the 14 original CIN(ROUT)=1 grades were oncogenic HPV (=HPV)-positive and five of these eight were upgraded by CIN(QP) to CIN 2 and CIN 3. These upgrades were in agreement with the blind reference revisions. The six HPV-negative CIN(ROUT)=1 cases were CIN 1 both by CIN(QP) and by CIN(REF). Thirteen of the 15 original CIN(ROUT)=2 grades were HPV-positive and seven of these were CIN(QP)=3. All six HPV-positive CIN(ROUT)=2 cases that were CIN(QP)=2 were also CIN(REF)=2 at blind revision. In conclusion, this study has shown firstly, that in CIN lesions, Ki-67 immunoquantitative features and the presence of oncogenic HPV are highly correlated, and also within one subjective CIN grade; secondly, that subjective impressions of SI90 are not as accurate or reproducible as quantitative image analysis results; and thirdly, that the routine application of QP CIN-grading gives results that are in very good agreement with CIN grades assessed by an expert. Thus, routine QP-grading may be used to correct the subjective grade assessed by non-expert pathologists.

Adult↗

PubMed2001

Global expression changes of constitutive and hormonally regulated genes during endometrial neoplastic transformation.

OBJECTIVE: Endometrioid endometrial carcinoma is caused by a combination of mutational events and hormonal factors. We used large-scale messenger RNA expression analysis to discover genes that distinguish neoplastic transformation and examine the patterns of tumor expression of those genes which are normally regulated during the menstrual cycle. METHODS: Expression of approximately 6000 unique genes was quantified in 4 normal (2 proliferative, 2 secretory) and 10 malignant endometria using Affymetrix Hu6800 GeneChip probe arrays. Expression differences between normal and malignant tissue groups were measured by a test of statistical significance comparing the individual t statistic for each gene to the distribution of maximum t statistics among all genes following 1001 permutations of the tissue group assignments (Permax test). Hormonally responsive genes, selected by comparison of proliferative and secretory subsets of normal endometria using a combination of filters applied to the group means and t test rankings, were then examined in the tumors. RESULTS: Fifty genes with a Permax <0.50 provided excellent discrimination between normal and malignant groups and were predominantly characterized by diminished expression levels in the cancers. We found that 100 genes which are hormonally regulated in normal tissues are expressed in a disordered and heterogeneous fashion in cancers, with tumors resembling proliferative more than secretory endometrium. CONCLUSION: Neoplastic transformation is accompanied by predominant loss of activity of many genes constitutively expressed in normal source tissues and absence of expression profiles which characterize the antitumorigenic progestin response.

Adult↗

PubMed2001

Comprehensive Cancer Centre Amsterdam Barrett Advisory Committee: first results.

BACKGROUND: Treatment and follow-up policy for Barrett's oesophagus are dependent on the grade of dysplasia. However, sampling error of random biopsy protocols and subjectivity of pathological grading may hamper endoscopic surveillance. METHODS: The Amsterdam Comprehensive Cancer Center Barrett Advisory Committee (BAC) is a regional multidisciplinary consultative working-group, offering revision of pathology, revision of pathology plus additional endoscopic diagnostics, or referral for treatment. RESULTS: Between July 1998 and July 1999 30 patients were referred to the B.A.C for advice; eighteen patients were referred because of suspicion of high grade dysplasia. Reassessment of biopsies, including additional quantitative pathology, with or without additional endoscopic diagnostics, led to adjustment of the grading of dysplasia in 15 patients (50%). A suspicion of low grade dysplasia was rejected in nine out of ten cases. Adjustment of the original diagnosis often influenced further therapy or follow-up. CONCLUSIONS: reassessment of conventional pathology, quantitative pathology, and additional diagnostic procedures might improve the accuracy of diagnosis and staging of malignant degeneration of Barrett's oesophagus, although experience is still limited. The complexity of the management of these patients demands a specialised multidisciplinary approach. A Barrett Advisory Committee can offer valuable contributions to the treatment of patients with Barrett's oesophagus.

Academic Medical Centers↗

PubMed2001

Expression of growth factors, growth factor receptors and apoptosis related proteins in invasive breast cancer: relation to apoptotic rate.

PURPOSE: To assess the relation between growth factors, growth-factor receptors, p53, bcl-2 and bax expression, and the rate of apoptosis in invasive breast cancer patients. MATERIALS AND METHODS: Tumors from 45 patients were assessed by immunohistochemistry for expression patterns of five growth factors and their receptors; platelet-derived growth factor A chain (PDGF-AA) and PDGF-receptor alpha (PDGFalphaR), PDGF-BB and PDGFbetaR, transforming growth-factor alpha (TGFalpha) and its receptor-epidermal growth factor receptor (EGFR) and vascular-endothelial growth factor (VEGF) and its receptors vascular-endothelial growth factor receptor I (FLT-1) and vascular-endothelial growth factor receptor II (FLK-1/KDR), two growth-inhibiting factors; transforming-growth factor beta I (TGFbeta1) and TGFbeta2 and their receptor couple TGFbeta receptor I (TGFbetaR-I) and TGFbetaR-II, and basic-fibroblast growth factor (bFGF). Besides, the expression patterns of the bcl-2, bax and p53 gene products were investigated. Expression patterns were correlated to the number of apoptotic cells assessed by light microscopy. RESULTS: PDGF-BB and bFGF showed a positive correlation with the AI (p = 0.006 and p = 0.030, respectively). EGFR expression was associated with a high number of apoptotic cells but did not reach significance (p = 0.10). None of the other individual growth factors, growth-inhibiting factors or receptors showed a significant relation with the AI. The presence of a possible auto- or paracrine loop of the TGFalpha/EGFR combination was associated with a high number of apoptotic cells but did not reach significance (p = 0.20). PDGF-AA, bFGF and EGFR expression showed a significant relation to p53 overexpression. TGFbeta2 expression showed an inverse correlation with p53 overexpression. CONCLUSION: We found an association between several growth factors and growth-factor receptors with number of apoptotic cells. This underlines the importance of growth factors and their receptors not just in proliferation, but also, directly and/or indirectly, in regulating the rate of apoptosis in invasive breast cancer. Growth factors and their receptors may therefore be useful as targets of anti-cancer therapy by inducing apoptosis or increasing the sensitivity of cells for chemo- or hormonal therapy induced apoptosis.

Apoptosis↗

PubMed2001

Cytogenetic characteristics of oral squamous cell carcinomas in Fanconi anemia.

Fanconi anemia (FA) is an autosomal recessive syndrome with a marked predisposition to malignancies, in particular acute myeloid leukemia and squamous cell carcinoma of the oral cavity. We examined oral squamous cell carcinoma tissue from two FA patients (FA-A and FA-C) by comparative genomic hybridization. Both tumors, which were negative for human papilloma as well as Epstein-Barr viral sequences, showed multiple alterations with a high proportion of whole-arm chromosomal gains and losses. This combination of features as well as the sites involved in chromosomal breakage are very similar to what is typically observed in non-FA oral tumors. These results suggest that the process leading to early occurrence of oral cancer in FA patients follows a similar pathway as in non-FA cancer patients, which would support a caretaker function for FA genes in the protection against oral carcinogenesis. Since FA patients are uniquely hypersensitive to DNA cross-linking agents, while oral cancer in the general population is thought to be environmentally induced, these results also suggest that environmental DNA cross-linkers may be causally involved in oral carcinogenesis.

Adult↗

PubMed2001

Comparative genomic hybridization of microdissected familial ovarian carcinoma: two deleted regions on chromosome 15q not previously identified in sporadic ovarian carcinoma.

The vast majority of familial ovarian cancers harbor a germline mutation in either the breast cancer gene BRCA1 or BRCA2 tumor suppressor genes. However, mutations of these genes in sporadic ovarian cancer are rare. This suggests that in contrast to hereditary disease, BRCA1 and BRCA2 are not commonly involved in sporadic ovarian cancer and may indicate that there are two distinct pathways for the development of ovarian cancer. To characterize further differences between hereditary and sporadic cancers, the comparative genomic hybridization technique was employed to analyze changes in copy number of genetic material in a panel of 36 microdissected hereditary ovarian cancers. Gains at 8q23-qter (18 of 36, 5 cases with high-level amplifications), 3q26.3-qter (18 of 36, 2 cases with high-level amplifications), 11q22 (11 of 36) and 2q31-32 (8 of 36) were most frequent. Losses most frequently occurred (in decreasing order of frequency) on 8p21-pter (23 of 36), 16q22-pter (19 of 36), 22q13 (19 of 36), 9q31-33 (16 of 36), 12q24 (16 of 36), 15q11-15 (16 of 36), 17p12-13 (14 of 36), Xp21-22 (14 of 36), 20q13 (13 of 36), 15q24-25 (12 of 36), and 18q21 (12 of 36). Comparison with the literature revealed that the majority of these genetic alterations are also common in sporadic ovarian cancer. Deletions of 15q11-15, 15q24-25, 8p21-ter, 22q13, 12q24 and gains at 11q22, 13q22, and 17q23-25, however, appear to be specific to hereditary ovarian cancer. Aberrations at 15q11-15 and 15q24-25 have not yet been described in familial ovarian cancer. In these regions, important tumor suppressor genes, including the hRAD51 gene, are located. These and other yet unknown suppressor genes may be involved in a specific carcinogenic pathway for familial ovarian cancer and may explain the distinct clinical presentation and behavior of familial ovarian cancer.

BRCA2 Protein↗

PubMed2001

Distinct chromosomal aberrations in Epstein-Barr virus-carrying gastric carcinomas tested by comparative genomic hybridization.

BACKGROUND & AIMS: Approximately 10% of gastric adenocarcinomas carry the human pathogenic Epstein-Barr virus (EBV). The role of EBV in the pathogenesis of these carcinomas remains to be established. METHODS: To obtain a comprehensive overview of chromosomal aberrations in EBV-carrying and EBV-negative gastric carcinomas we performed comparative genomic hybridization (CGH) on 44 gastric carcinomas, 10 EBV-positive, and 34 EBV-negative. Additionally, DNA flow cytometry was done. RESULTS: Loss of chromosome 4p (P < 0.001) and of 11p (P < 0.02) was exclusively restricted to EBV-carrying gastric carcinomas. In addition, loss of 18q (P < 0.02) was significantly more frequent in EBV-carrying gastric carcinomas. The latter involves loci, which have already been linked to gastric carcinogenesis such as the DCC and SMAD4 gene. In contrast, the losses on chromosome 4 and 11 do not yet harbor a gene related to gastric carcinogenesis. No significant correlation was found between DNA-ploidy and the EBV-status. A number of chromosomal aberrations were found at comparable frequencies in both groups, i.e., losses of chromosome 17, 12q, and loss of 1p. Interestingly, gains of 13q (10/34) and 3q (5/34) and loss of 1q (5/34) were solely observed in EBV-negative gastric carcinomas. CONCLUSIONS: These data indicate that EBV-carrying and EBV-negative gastric carcinomas have different pathogenetic pathways in which EBV might play a crucial role.

Adenocarcinoma↗

PubMed2001

Prospective multicenter evaluation of the morphometric D-score for prediction of the outcome of endometrial hyperplasias.

Prospective multicenter evaluation of the WHO classification and the morphometric D-score to predict endometrial hyperplasia cancer progression. In 132 endometrial hyperplasias WHO classification was performed by two experienced gynecologic pathologists. The D-score was assessed blindly by technicians in a routine diagnostic setting. Development of endometrial carcinoma during a 1-10-year follow-up was used as the end point. Eleven of 132 patients (8%), 10 of 61 (16%) atypical hyperplasias, and 1 of 71 (1%) nonatypical hyperplasias developed cancer. Twenty-six curettings had a D-score < or = 0 ("unfavorable" or endometrial intraepithelial neoplasia) of which 10 (38%) developed cancer. None of the 86 cases with a D-score > 1 ("favorable") and one of the 20 (5%) cases with 0 < D-score < or = 1 ("uncertain") developed cancer. Sensitivity of the D-score was 100%, specificity 82%, the positive and negative predictive values were 38% and 100%, respectively. These values are similar to those in three prior retrospective D-score studies but higher than the WHO values (which are 91%, 58%, 16%, and 99%, respectively). The D-score in endometrial hyperplasias is a more sensitive and specific marker for cancer prediction than the WHO classification, can be assessed in a routine clinical setting on standard hematoxylin and eosin sections (15-30 minutes per case), and is highly reproducible and cost-effective (U.S. $50 per case).

Adult↗

PubMed2001

Hemostatic imbalance in active and quiescent ulcerative colitis.

OBJECTIVE: In healthy conditions, factors inducing or inhibiting coagulation and factors inducing or inhibiting fibrinolysis are in balance. In ulcerative colitis, hypercoagulation is presumed, which may explain part of the clinical features of this disease. Therapy strategies affecting hemostasis may improve the course of ulcerative colitis. This study was conducted to evaluate the balance of coagulation and fibrinolysis in the course of treatment of active ulcerative colitis. METHODS: Patients with active ulcerative colitis were studied by serial determination of markers of the coagulation cascade (thrombin-antithrombin complexes and fibrin degradation products [FbDP]) and the fibrinolytic cascade (fibrinogen degradation products [FgDP]). Parameters of inflammation were also measured (C-reactive protein [CRP], erythrocyte sedimentation rate [ESR], albumin, platelet count, and fibrinogen). Disease activity was assessed by endoscopic and histopathological scores. Follow-up measurement was performed in the course of treatment at the third or fourth month after baseline. Measurements were compared with healthy controls. RESULTS: Thirty-three patients and 22 healthy controls were included. During active ulcerative colitis, inflammatory parameters (CRP, ESR, platelet count) and hemostatic parameters (thrombin-antithrombin complexes, fibrinogen, FgDP, and FbDP) were elevated in comparison with healthy controls. Albumin was decreased and antithrombin-III remained unchanged. During treatment, disease activity decreased significantly endoscopically and histopathologically (p < 0.001). CRP, ESR, platelet count, and fibrinogen also decreased significantly. The hemostatic balance, expressed as the ratio between the plasmin-dependent generation of FgDP and coagulation-dependent generation of FbDP, increased from 0.69 to 1.12 during treatment, mainly because of a decrease of FbDP. In healthy controls, this ratio was CONCLUSIONS: The coagulation and fibrinolytic cascades were activated in active ulcerative colitis, with a hemostatic imbalance in favor of coagulation. This hypercoagulability persisted in 20% (7/33) of patients with ulcerative colitis in remission. The decrease of FbDP and the increase in the FgDP/FbDP ratio during reconvalescence of ulcerative colitis showed that the coagulation cascade was more activated than the fibrinolytic cascade in active disease.

Adult↗

PubMed2001

Quantitative assessment of gastric corpus atrophy in subjects using omeprazole: a randomized follow-up study.

OBJECTIVES: Atrophy of the gastric mucosa most frequently results from chronic Helicobacter pylori infection and is a risk factor for the development of gastric cancer. Profound acid suppression has been suggested to accelerate the onset of gastric mucosal atrophy. The aim of the present study was to evaluate the effects of H. pylori eradication and acid inhibition by omeprazole on gastric atrophy by means of quantitative analysis of tissue morphology. METHODS: Corpus biopsy specimens were obtained during endoscopy in 71 gastroesophageal reflux disease (GERD) patients at baseline and after 3 and 12 months. A total of 48 subjects were H. pylori positive and 23 were H. pylori negative. All subjects received omeprazole 40 mg once daily after the first endoscopy for 12 months. After randomization, 27 of the 48 H. pylori-positive patients also received eradication therapy. In hematoxylin and eosin-stained slides the volume percentages of glands (VPGL), volume percentages of stroma (VPS), and volume percentages of infiltrate (VPI) were measured in the glandular zone of the mucosa. The results were evaluated by computerized morphometric analysis. RESULTS: In the eradication group, the mean VPGL increased from 63.0% to 67.7% and 71.5% after 3 and 12 months (p < 0.001), respectively. The mean VPS and VPI decreased from 33.1% and 4.0% to 29.3% and 3.0% and to 26.4% and 2.1% (p < 0.001 and p = 0.04), respectively. Patients with the lowest VPGL at baseline showed the largest increases of VPGL after eradication treatment as compared to patients with high a VPGL at baseline. In the H. pylori-persistent group the VPI showed a significant increase (p = 0.01), and in the H. pylori-negative group VPGL increased significantly from 71.9% to 75.2% (p = 0.03) after 12 months. CONCLUSIONS: Eradication of H. pylori leads to restitution of the volume percentage of glandular epithelium to normal levels, even during treatment with proton pump inhibitors. Whether this effect can also be seen in patients with marked atrophy needs further investigation.

Adult↗

PubMed2001

Rapid quantitative assessment of gastric corpus atrophy in tissue sections.

BACKGROUND/AIMS: Grading of Helicobacter pylori induced atrophic gastritis using the updated Sydney system is severely limited by high interobserver variability. The aim of this study was to set up a quantitative test of gastric corpus mucosal atrophy in tissue sections and test its reproducibility and correlation with the Sydney scores of atrophy. METHOD: Mucosal atrophy was assessed in 124 haematoxylin and eosin stained corpus biopsy specimens by two experienced gastrointestinal pathologists (EB, JL) according to the updated Sydney system as none (n = 33), mild (n = 33), moderate (n = 33), or pronounced (n = 25). In each specimen, the proportions of glands, stroma, infiltrate, and intestinal metaplasia in the glandular zone were measured as volume percentages using a point counting method. The optimal point sample size, intra-observer and interobserver reproducibility, discriminative power for degrees of atrophy, and correlations with H pylori status were evaluated. RESULTS: Counting 400 points in 200 fields of vision provided the smallest sample size that still had excellent intra-observer and interobserver reproducibility (r > or = 0.96). Overall, the volume percentage of glands (VPGL), infiltrate (VPI), and stroma (VPS) correlated well with the Sydney scores for atrophy (p < or = 0.003). However, no differences were found between non-atrophic mucosa and mild atrophy. No correlation was found between age and either the Sydney grade of atrophy or the VPGL or VPS. In non-atrophic mucosa and mild atrophy, H pylori positive cases showed a significantly higher VPI than did H pylori negative cases. A lower VPGL was seen in H pylori positive cases than in H pylori negative cases in the mild atrophy group. VPS did not correlate with H pylori status within each grade of atrophy. CONCLUSION: Point counting is a powerful and reproducible tool for the quantitative analysis of mucosal corpus atrophy in tissue sections. These data favour the combination of "none" and "mild" atrophy into one category, resulting in a three class grading system for corpus atrophy, when using the updated Sydney system.

Adult↗

PubMed2001

Improved objectivity of grading of T(A,1) transitional cell carcinomas of the urinary bladder by quantitative nuclear and proliferation related features.

AIM: To analyse whether the mean nuclear area of the 10 largest nuclei (MNA-10), the mitotic activity index (MAI), and Ki-67 immunoquantitative features have additional value to discriminate different grades of T(A,1) transitional cell carcinoma (TCC) of the urinary bladder. MATERIALS/METHODS: One hundred and fifty of 200 consecutive cases (75%) showing interobserver agreement on duplicate blind grade assessment by independent pathologists were studied. Using random numbers, the 150 cases were divided into sets for learning (n = 75) and testing (n = 75). Single and multivariate analyses were applied to discriminate the different grades in the learning set. The multivariate classifier developed in this way was evaluated in the test set (n = 75). RESULTS: With the MNA-10 alone, using the classification MNA-10 < 80 microm(2) = grade 1, 80 microm(2) < MNA-10 < 130 microm(2) = grade 2, MNA-10 > 130 microm(2) = grade 3, 71% of all 150 cases were correctly classified (69% of grade 1 v grade 2 and 76% of grade 2 v grade 3). With multivariate analysis, the best discriminating features in the learning set (17 grade 1, 30 grade 2, and 28 grade 3) between grades 1 and 2 were MNA-10 and MAI, and between grades 2 and 3 MAI and Ki-67. With these features, 94% of grade 1 v grade 2 and 97% of grade 2 v grade 3 were correctly classified in the learning set (overall, 95% correct, none of the grade 3 cases misclassified). In the test set the classification results were similar. When the three grades were entered at the same time for discrimination, Ki-67 area % and MAI was the best discriminating combination, both in the sets for learning and testing. Overall correct classification results in the sets for learning and testing were slightly lower, but still 94% and 92%. Most importantly, none of the grade 3 cases was misclassified; the classification shifts all occurred between grades 1 and 2. CONCLUSIONS: The combination of MNA-10, MAI, and Ki-67 gives much better discrimination between grades 1, 2, and 3 in T(A,1) TCC of the urinary bladder than MNA-10 alone. The similarity of the classification results of the learning set and test set are encouraging and this quantitative pathological grading model should be applied in a prospective study.

Aged↗

PubMed2001

Fourth updated ESACP consensus report on diagnostic DNA image cytometry.

A task force of experts in the field of diagnostic DNA image cytometry, invited by the ESACP, and further scientists or physicians revealing experience in that diagnostic procedure (names are given in Addendum A), agreed upon the following 4th updated Consensus Report on Standardised Diagnostic DNA Image Cytometry during the 7th International Congress of that society in Caen, 2001. This report is based on the three preceding ones [6,14,17]. It deals with the following items:- Critical review and update of the definitions given in the 1997 Consensus Update;- Review and detailed description of basic terms, principles and algorithms for diagnostic interpretation;- Recommendations concerning diagnostic or prognostic applications in specific fields of tumour pathology. This update is not aimed to substitute the 1997 consensus, but to make necessary addenda and give more detailed descriptions of those items not unequivocally to interpret by potential users of the methodology.

Algorithms↗