Proliferation Rate Ki-67 Research Articles

Expression of metallothionein I/II and Ki-67 antigen in various histological types of basal cell carcinoma

Basal cell carcinoma (BCC) is the most frequent skin cancer, with many different histological subtypes. Recent studies have investigated the expression of proliferative markers, but little is known about the expression of metallothioneins (MT) in different histological subtypes of this cancer and their impact on proliferation intensity in BCC. In this study, we examined MT-I/II expression by immunohistochemistry in 58 different histological subtypes of BCC (38 nodular, six adenoid, eight infiltrative, and six metatypic cases) and correlated its expression with tumor size and Ki-67 proliferation rate. Statistical analysis revealed no significant differences in the expression of studied markers in regard to the histological subtype. A positive correlation between MT and Ki-67 expression was observed for all the studied cases (r = 0.26; p = 0.049), but was even stronger in the metatypic subtype of BCC (r = 0.85; p = 0.033). MT and Ki-67 expression did not correlate with tumor size. In conclusion, it seems that metallothioneins may have an impact on the proliferation rate of BCC, but further studies are required to determine whether MT may be a risk factor of recurrences.

Phase II study of a novel neoadjuvant chemotherapy (NAC) for breast cancer (BC).

1060 Background: The goal of this NAC study was to improve the pathologic response of pts with localized BC. Methods: 51 pts with localized BC >1 cm were treated with this novel regimen consisting first of docetaxel 75 mg/m2, epirubicin 80 mg/m2, and cyclophosphamide 500 mg/m2 (TEC) and PEG Filgrastim for 4 cycles. Pretreament PET scan was done and repeated after course 1. Following the 4th course, ER+/HER2- patients received 4 additional TEC cycles if they achieved CR by MRI, or were switched to a non cross-resistant regimen (vinorelbine, bevacizumab, capecitabine) if they had < CR. HER2+ pts were given docetaxel + trastuzumab for 4 additional cycles, or were switched to a different regimen if < PR. MD Anderson residual cancer burden (MDARCB) score was used to measure pathologic response and correlation with several prognostic factors was studied. Results: Median age = 53; 27 were postmenopausal; 42 had invasive ductal carcinoma, 5 invasive lobular; 12 triple negative, 11 HER2+, and 28 ER+ or PR+/HER2-. MDARCB was significantly better in HER-2+ and triple negative tumors (table). ER+ or PR+/Her2- pts had the least favorable MDARCB with none achieving 0 and only 21% attaining MDARCB=1. 59% of pts with > 5% SUV drop attained MDARCB score 0-1 vs 13% with ≤ 5% drop. %Ki-67 correlated well with MDARCB (table). Ki-67 correlated well with receptor status: 85% of Triple Neg or Her2+ pts had Ki-67 >17 vs only 29% of ER+ or PR+/Her2-. Conclusions: a) This novel NAC regimen leads to markedly favorable MDARCB scores in triple negative and Her-2+ cases. b) Several factors may be useful in predicting response to chemotherapy, including receptor status, Ki-67, and PET scan response after 1st chemotherapy course. c) Ki-67 proliferative rate is closely correlated with receptor status. d) Early PET could be used to predict MDARCB. The challenge now is to improve response in ER+ or PR+/Her2- pts. [Table: see text]

Peptide receptor radionuclide therapy for neuroendocrine tumors in Germany: Initial results of a multiinstitutional cancer registry.

e14513 Background: Peptide receptor radionuclide therapy is an effective treatment option for patients with well differentiated somatostatin receptor expressing neuroendocrine tumors. However, published data results mainly from retrospective monocentric studies. Methods: We initiated a multi-institutional, prospective and board reviewed registry for patients treated with Peptide receptor radionuclide therapy in Germany in 2009. Results: In five centers, 297 patients were registered. Primary tumors were mainly derived from pancreas (117/297), small intestine (80/297) whereas 56 were of unknown primary. Most tumors were well differentiated with a median Ki67 proliferation rate of 5% (range 0.9 to 70). Peptide receptor radionuclide therapy was performed using mainly Yttrium-90 and/or Lutetium-177 as radionuclides in 1-8 cycles. Mean overall survival was estimated at 213 months with a follow up between 1 and 230 months after initial diagnosis and 87 months with a follow up between 1 and 92 months after start of Peptide receptor radionuclide therapy. Median overall survival was not yet reached. Subgroup analysis demonstrated that best results were obtained in neuroendocrine tumors with a proliferation rate below 20%. Conclusions: Our results indicate that Peptide receptor radionuclide therapy is an effective treatment well and moderately differentiated neuroendocrine tumors irrespective of previous therapies and should be regarded a one of the primary treatment options for patients with neuroendocrine tumors.

Notch-1 and Notch-4 Biomarker Expression in Triple-Negative Breast Cancer

Triple-negative breast cancer (TNBC) demonstrates lack of expression of hormone receptors and human epidermal growth factor receptor. However, there is no targeted therapy for TNBC. The authors analyzed 29 TNBC cases for Notch-1 and Notch-4 biomarker expression and subcellular location, Ki67 proliferation rate, and relevant clinical/survival data. Results demonstrated an unfavorable Ki67 rate in 90% of cases, Notch-1 expression in tumor and endothelial cells in 100% of cases, and Notch-4 expression in tumor cells in 73% of cases and endothelial cells in 100% of cases. Additionally, subcellular localization of Notch-1 and Notch-4 was predominantly nuclear and cytoplasmic. In conclusion, (a) the majority of TNBCs are high-grade infiltrating ductal carcinomas with high Ki67 proliferation rate and (b) both Notch-1 and Notch-4 receptors are overexpressed in tumor and vascular endothelial cells with subcellular localization different from that of hormone-positive breast cancer. Targeting Notch signaling with gamma secretase inhibitors should to be explored to further improve the survival rate of TNBC patients.

Tailoring Therapy for Locally Advanced Breast Cancer Using Molecular Profiles

The term 'locally advanced breast cancer' covers a range of clinical scenarios, and has the implications that surgical clearance and local control will be difficult or impossible, and long-term survival rates will be poor. Treatment selection is particularly important in this group of patients to try to obtain maximum control of disease, and potentially improve surgical options and cure rates. Currently, assessment of estrogen receptor, progesterone receptor and human epidermal receptor 2 status in tumour samples remains the gold standard for prediction of response to endocrine therapy, chemotherapy or targeted agents such as trastuzumab. Progress has been made in identifying markers that can help select treatments likely to be associated with response and avoid those associated with resistance. These potential markers include Ki67 proliferation rate, cytochrome P450 (CYP) 2D6 expression, BRCA1/2 gene status and others.

Abstract 3135: Notch 1 and notch 4 biomarker expression in triple-negative invasive breast cancer

Abstract BACKGROUND: Triple-negative breast cancer (TNBC) is a high-grade tumor showing lack of expression of estrogen and progesterone receptors and human epidermal growth factor receptor (HER-2/neu). Unlike hormone receptor and HER-2/neu positive breast carcinomas, there is no targeted therapy for TNBC. The objective of this study is to investigate Notch 1 and Notch 4 biomarker expression in TNBC and to correlate the expression with known prognostic factors. DESIGN: We performed a retrospective chart review of 29 TNBC during 1998-2007. Data collected included age at diagnosis, histological type and grade, Ki67 proliferation rate, and patient survival status. Formalin-fixed paraffin embedded tissue blocks from each TNBC was selected. Notch 1 and Notch 4 expression were analyzed by immunohistochemical method (Santa Cruz Biotechnology Inc, USA). The intensity of staining for Notch 1 and 4 expressions and the sub-cellular localization of these receptors (cytoplasmic or nuclear) in tumor epithelial cells and vascular endothelial cells were noted. Only strong cytoplasmic and/or nuclear staining was documented as positive for Notch expression. Student's t test and chi-square test were applied for data analysis. RESULTS: Age of the patients ranged from 37 to 83 years (mean 57.7). Twenty-seven tumors were infiltrating ductal carcinomas (93.1%) and 2 were infiltrating papillary carcinomas (6.9%). Twenty-one cases were grade 3 (72.4%), 7 were grade 2 (24.2%) and one was grade 1 (3.4%). Unfavorable Ki67 proliferation rate (>20%) was seen in 26 (90%), borderline rate (10-20%) in 2 (6.9%) and favorable rate (<10%) in one (3.1%). Notch 1 expression was evaluable in 25 and Notch 4 in 29 cases. Notch 1 expression was present in 25/25 (100%) cases in tumor cells and in vascular endothelial cells. Notch 4 was expressed in tumor cells in 21/29 (73%) and in vascular endothelial cells in 29/29 (100%). Notch 4 expression was negative in tumor cells in 8/29 (27%) cases. Notch 1 and Notch 4 expression in tumor cells and in vascular endothelial cells are correlated with tumor grade (p<0.05) and Ki67 proliferation rate (p<0.05) in TNBC. Follow-up period ranged from 4-9 years (mean 5.3). Twenty-one patients are alive and well (72.4%), 2 are alive with disease (6.9%), 4 patients died of disease (13.8%), and 2 patients died of causes unrelated to disease (6.9%). CONCLUSION: This study demonstrates that (1) majority of triple-negative invasive breast cancers are morphologically high grade infiltrating ductal carcinomas with high Ki 67 proliferation rate, (2) both Notch 1 and Notch 4 receptors are over-expressed in tumor cells and in vascular endothelial cells in majority of this molecular subset of breast carcinoma, and (3) this subtype is associated with high overall survival rate with the currently available treatment. Targeting Notch signaling with gamma secretase inhibitors needs to be explored to further improve the survival rate of TNBC patients. Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 102nd Annual Meeting of the American Association for Cancer Research; 2011 Apr 2-6; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2011;71(8 Suppl):Abstract nr 3135. doi:10.1158/1538-7445.AM2011-3135

Status of HER-2/neu receptors and Ki-67 in breast cancer of Indian women

Background:Breast cancer is a leading cause of death in women. Receptor status is the most important prognostic and predictive marker for breast cancer.Aims:The present study was conducted with an aim to analyze breast cancer of Indian women with discordant receptor status, probably hormone dependent estrogen receptor (ER) positive, progesterone receptor (PgR) negative or ER– negative and PgR+ positive subgroup profile, infiltrating ductal breast cancer (IDC) not otherwise specified.Materials and Methods:Specimens from 100 IDC were grouped into three categories according to hormonal status (group 1: ER+ positive and PgR+ positive, group 2: ER+ positive and PgR– negative or ER– negative and PgR+ positive, group 3: ER– negative and PgR– negative) evaluated prognostic parameters.Statistical Analysis:Statistically significant difference was found between tumor receptor status distribution and menopausal status (P = 0.0235), age of patients (P < 0.001), histopathologic grade (P < 0.001), vascular invasion (P = 0.006), HER-2/neu status (P = 0.004) and Ki-67 proliferation rate (P < 0.001).Results:Group 1 tumors were found exclusively in post-menopausal patients with average age 68.9 years, most of which had intermediate grade II, without vascular invasion, with HER-2/neu status score predominantly 0 or 1+ and lower Ki-67 proliferation rate. Group 2 tumors were found predominantly in younger post-menopausal patients with average age 57.5 years, with vascular invasion found in 23% of cases. Group 3 tumors mostly had higher histopathologic grade, showed the highest percentage of the Ki-67 positive tumor cells and vascular invasion in 30% of the cases.Conclusion:It is concluded that patients with group 2 breast cancer were younger post-menopausal women, with tumors moderately differentiated, HER-2/neu score 0 or 1+ and with lower Ki-67 proliferation rate.

Ki-67 Proliferation Rate as a Prognostic Marker in Major Salivary Gland Carcinomas

The study was performed to evaluate the prognostic relevance of cell proliferation associated with Ki-67/ Mib-1 immunostaining in malignant tumors of the major salivary glands. Cell proliferation was evaluated by Mib-1 antibody against Ki-67 antigen in 41 patients with cancer of the parotid or submandibular glands, including 14 acinic cell carcinomas, 12 ductal carcinomas, 7 mucoepidermoid carcinomas, 5 carcinomas ex pleomorphic adenoma, 1 adenoid cystic carcinoma, 1 undifferentiated carcinoma, and 1 polymorphous low-grade adenocarcinoma. Patients with Ki-67 values of more than 15% and those with Ki-67 values of 15% or less differed both in disease-free survival (p < 0.001) and in overall survival (p < 0.001). We evaluated the association between Ki-67 and time to recurrence in correlation to age, sex, ductal histotype, and N stage; the Cox regression model was significant (p = 0.013). In the group of patients with T1 and T2 cancers, those with Ki-67 values of 15% or less had better survival rates than did those with Ki-67 values of more than 15% (p = 0.004). In the group of patients with N0 cancers, those with Ki-67 values of 15% or less had a better survival than did those with Ki-67 values of more than 15% (p < 0.001). To our knowledge, this is the first study to stratify different risk classes in early T1-T2 or N0 malignant tumors of the major salivary glands that identified aggressive lesions with elevated Ki-67 expression at an initial stage.

Gata3-deficient mice develop parathyroid abnormalities due to dysregulation of the parathyroid-specific transcription factor Gcm2

Heterozygous mutations of GATA3, which encodes a dual zinc-finger transcription factor, cause hypoparathyroidism with sensorineural deafness and renal dysplasia. Here, we have investigated the role of GATA3 in parathyroid function by challenging Gata3+/- mice with a diet low in calcium and vitamin D so as to expose any defects in parathyroid function. This led to a higher mortality among Gata3+/- mice compared with Gata3+/+ mice. Compared with their wild-type littermates, Gata3+/- mice had lower plasma concentrations of calcium and parathyroid hormone (PTH) and smaller parathyroid glands with a reduced Ki-67 proliferation rate. At E11.5, Gata3+/- embryos had smaller parathyroid-thymus primordia with fewer cells expressing the parathyroid-specific gene glial cells missing 2 (Gcm2), the homolog of human GCMB. In contrast, E11.5 Gata3-/- embryos had no Gcm2 expression and by E12.5 had gross defects in the third and fourth pharyngeal pouches, including absent parathyroid-thymus primordia. Electrophoretic mobility shift, luciferase reporter, and chromatin immunoprecipitation assays showed that GATA3 binds specifically to a functional double-GATA motif within the GCMB promoter. Thus, GATA3 is critical for the differentiation and survival of parathyroid progenitor cells and, with GCM2/B, forms part of a transcriptional cascade in parathyroid development and function.

Follicular lymphomas with and without translocation t(14;18) differ in gene expression profiles and genetic alterations

AbstractFollicular lymphoma (FL) is genetically characterized by the presence of the t(14;18)(q32;q21) chromosomal translocation in approximately 90% of cases. In contrast to FL carrying the t(14;18), their t(14;18)-negative counterparts are less well studied about their immunohistochemical, genetic, molecular, and clinical features. Within a previously published series of 184 FLs grades 1 to 3A with available gene expression data, we identified 17 FLs lacking the t(14;18). Comparative genomic hybridization and high-resolution single nucleotide polymorphism (SNP) array profiling showed that gains/amplifications of the BCL2 gene locus in 18q were restricted to the t(14;18)-positive FL subgroup. A comparison of gene expression profiles showed an enrichment of germinal center B cell–associated signatures in t(14;18)-positive FL, whereas activated B cell–like, NFκB, proliferation, and bystander cell signatures were enriched in t(14;18)-negative FL. These findings were confirmed by immunohistochemistry in an independent validation series of 84 FLs, in which 32% of t(14;18)-negative FLs showed weak or absent CD10 expression and 91% an increased Ki67 proliferation rate. Although overall survival did not differ between FL with and without t(14;18), our findings suggest distinct molecular features of t(14;18)-negative FL.

PI3 kinase activation and response to trastuzumab or lapatinib in HER-2 overexpressing locally advanced breast cancer (LABC).

Abstract Abstract #34 Background: Activating mutations of PI3 kinase (PIK3CA) and PTEN loss may be associated with trastuzumab resistance. Trastuzumab, a HER2 humanized monoclonal antibody, and lapatinib, an EGFR/HER2 tyrosine kinase inhibitor are both established treatments. Greater understanding of the cellular response to trastuzumab or lapatinib is needed to tailor targeted therapy for individual patients and identify those less likely to benefit. Material and Methods: We performed two sequential neoadjuvant clinical trials in HER-2 overexpressing LABC: 40 patients received weekly trastuzumab at standard doses given initially as a single agent for the first 3 weeks, then in combination with 3-weekly docetaxel for 12 weeks (T), while 49 patients received lapatinib as a single agent (1,500 mg daily, orally) for 6weeks then the combination of 3-weekly trastuzumab/docetaxel for 12 weeks, before primary surgery (L). Sequential core biopsies of the primary breast tumors were taken at initial, weeks 1 and 3 after the first dose of trastuzumab, and at initial, weeks 2, 4, and 6 after lapatinib. Apoptosis, Ki67 proliferation rate, and PTEN were assessed by immunohistochemistry. Low PTEN was defined as Allred score of &amp;lt;3. Genomic DNA (10-100ng) was sequenced using the BigDye Terminator Cycle Sequencing Kit (Applied Biosystems) and an ABI 3730 automated capillary sequencer. Two sample and paired sample comparisons were performed using nonparametric tests. Results: There was a significant decrease in clinical tumor size after three weeks of trastuzumab (n=35, median=-20%), and six weeks of lapatinib (n=49, median=-74%) compared to pre-therapy (p&amp;lt;0.001). At surgery, pathologic complete response was observed in 38% in patients on upfront T and 70% patient on L. There was a significant increase in apoptosis (median=3.5% to 4.7%, p=0.006) within one week after trastuzumab, with no significant change in Ki67 at any of the time point. Lapatinib was associated with a no significant increase in apoptosis but a significant decrease in Ki67 at week 2, 4, and 6 of therapy (p&amp;lt;0.001). Cases with low PTEN or PIK3CA mutations were significantly less likely to have a pathologic complete response to T (p&amp;lt;0.005). Howver, low PTEN or PIK3CA mutations was not significantly associated with pathologic resistance to L. Conclusions: Activation of PI3 kinase pathway is associated with trastuzumab but not lapatinib resistance. Lapatinib may affect signalling through the Ras/Raf/MAPK/ERK pathway, inhibiting cell division. Low PTEN expression was not associated with lapatinib resistance, and may explain the clinical efficacy of lapatinib in trastuzumab-resistant patients, supporting clinical trials for the combination of both agents. Citation Information: Cancer Res 2009;69(2 Suppl):Abstract nr 34.

Molecular characteristics and predictors of survival in patients with malignant neuroendocrine tumors

To better understand the molecular pathogenesis of neuroendocrine tumors (NET), we investigated the molecular and clinical characteristics of malignant poorly differentiated colorectal NET and compared these findings with sporadic CRC and well-differentiated benign and malignant fore-/midgut NET. Tumors were analyzed and correlated for microsatellite instability (MSI) and the CpG island methylator phenotype (CIMP). NET were scored for proliferation using Ki-67. A total of 34 malignant poorly differentiated colorectal NET, 38 well-differentiated benign and malignant fore-/midgut-NET and 150 sporadic colorectal cancers (CRC) with known MSI status were investigated. Among the sporadic CRC, CIMP was significantly correlated with MSI-high (MSI-H) (p < 0.001). Of the 34 colorectal NET, 0/1 of the MSI-H, 3/5 (60%) of the MSI-L and 13/19 (68%) of the MSS tumors were CIMP+ (p = 0.17). Of the fore-/midgut-NET, none was MSI-H. 20/34 (59%) colorectal NET vs. 11/38 (29%) fore-/midgut-NET were CIMP+ (p = 0.01). The Ki-67 index was significantly higher in poorly differentiated colorectal NET compared to the less malignant fore-/midgut-NET (p < 0.0001). Besides the location in the colon, Ki-67 predicted poor outcome in NET (p < 0.0001). CIMP status did not affect survival. In NET, p16 methylation predicted a poor outcome (p = 0.0004). We conclude that molecular pathogenesis in sporadic CRC and poorly differentiated colorectal NET is different despite some similarities. Main differences between malignant well-differentiated and poorly differentiated NET are the Ki-67 proliferation rate and differential methylation in tumor-associated genes. Predictors of a poor outcome in patients with NET are poor differentiation, a high Ki-67 index and p16 methylation.

Frequency of the basal‐like phenotype in African breast cancer

Basal-like breast carcinoma has been recognized as a subtype with specific prognostic implications. However, there is a lack of reports about this category of breast tumors in African women. The aim of this study was to explore the basal-like phenotype in breast cancer patients in an African population, and a registry-based series was included from the well-defined Kyadondo County in Uganda (1.7 millions). We studied a total of 65 archival paraffin blocks of invasive breast cancer using antibodies against cytokeratin 5/6 and P-cadherin, and these markers were expressed in 34% of all cases and in 52% of ER (estrogen receptor)-negative tumors. All basal-like tumors were ER negative (p<0.0005) and PR (progesterone receptor) negative (p=0.002). Basal-like breast carcinomas were of a higher histologic grade (p=0.001), had high mitotic counts (p=0.002), and marked nuclear pleomorphism (p=0.002). P-cadherin-positive tumors had a high Ki-67 proliferative rate (p=0.039). In conclusion, the basal-like phenotype is frequent in this African series of breast cancer and is strongly associated with poor prognostic factors. Our findings might be significant in relation to clinical management of these patients, including novel targeted therapy.

Histologic and Immunohistochemical Changes in the Stented Common Bile Duct

Many patients with pancreatic carcinoma have stent placement for biliary obstruction before resection. Stent-associated atypia, found in common bile duct (CBD) margins at the time of resection, may be confused with malignancy. We evaluated histologic and immunohistochemical changes in CBD margins from resection specimens for pancreatic carcinoma. Histologic findings in CBDs, including ulcer and inflammation; epithelial metaplasia, atypia, and gland complexity; and increased wall thickness, nerve entrapment, and smooth muscle content, were compared in 30 stented and 31 nonstented CBD margins from pancreaticoduodenectomies for carcinoma and 13 normal CBDs from autopsy material. The proliferation index was calculated for stented and nonstented CBDs after Ki-67 immunohistochemical staining. Immunostaining for Ki-67, p53, and c-erbB-2 was performed in stented CBDs and corresponding carcinomas. All the histologic changes occurred more frequently in stented and nonstented CBD margins from carcinoma patients than in normal CBDs. Stented CBDs had significantly increased epithelial changes and Ki-67 proliferation rate as compared with nonstented CBDs. The stented CBDs had significantly less p53 and c-erbB-2 expression as compared with corresponding pancreatic carcinomas. Caution should be applied when interpreting atypia in CBD margins from patients with a history of CBD stenting. Changes found in stented CBDs are characteristic, and in most cases can be distinguished from malignancy. In difficult cases, immunohistochemistry may be useful.

Microvascular density and endothelial area correlate with Ki-67 proliferative rate in the canine non-Hodgkin's lymphoma spontaneous model

Experimental and clinical data indicate that tumor progression and malignancy are associated with increased angiogenesis and higher Ki-67 proliferation rate. Furthermore, increased angiogenesis and higher Ki-67 proliferation rate are associated with a poor prognosis, in both solid and hematological malignancies. However, no data have been published concerning the relationship between angiogenesis and Ki-67 proliferation rate in canine non-Hodgkin's lymphoma (NHL), a neoplasm that shares several biological and clinical characteristics with human NHL. This study has evaluated the relationship between angiogenesis and Ki-67 proliferation rate in a series of 58 canine NHL. Results showed that microvascular density (MVD), endothelial area (EA) and Ki-67 (MIB-1) are significantly correlated and that all the above indexes paralleled with the malignancy degree of NHL. These data suggest a biological link between angiogenesis and Ki-67 proliferation rate in canine NHL, which represents an interesting model to study the role of angiogenesis and proliferative activity as inter-species pathways of tumoral malignancy and biological aggressiveness.

911 POSTER Expression of FLICE-like inhibitory protein (c-FLIPL) is associated with ovarian cancer patient's chemoresistance

Gastro-intestinal neuroendocrine tumours (GI-NETs) are chemotherapy-resistant tumours. Bevacizumab, an inhibitor of vascular endothelial growth factor (VEGF), has shown promising results in several phase II trials of gastro-entero-pancreatic-NETs. We assessed bevacizumab combined with capecitabine, specifically in GI-NET patients.BEvacizumab in The Treament of neuroEndocrine tumoRs (BETTER) was a multicentre, open-label, non-randomised, two-group phase II trial. Here we present the group of patients with progressive, metastatic, well-differentiated GI-NETs. Patients Eastern Cooperative Oncology Group-performance status (ECOG-PS) ⩽ 2, Ki-67 proliferation rate <15% and no prior systemic chemotherapy were treated with bevacizumab (7.5 mg/kg/q3w) and capecitabine (1000 mg/m2 twice daily, orally d1–14, resumed on d22) for 6–24 months. The primary end-point was progression-free survival (PFS); secondary end-points included overall survival (OS), response rate, safety and quality of life.Of the 49 patients included, 53% were men, median age was 60 years (41–82), primary tumour site was ileal in 82% patients and Ki-67 was <15% in 48 patients and not available for one patient. After a maximum of 24 month follow-up per patient, the median PFS by investigator assessment was 23.4 months [95% confidence interval (CI): 13.2; not reached] and the overall disease control rate was 88% (18% partial response, 70% stable disease). The 2-year survival rate was 85%. Median OS was not reached. The most frequent grade 3–4 adverse events were hypertension (31%), diarrhoea (14%) and hand-foot syndrome (10%).The combination of bevacizumab and capecitabine showed clinical activity and a manageable safety profile in the treatment of GI-NETs that warrant confirmation in a randomised phase III trial.

Biomarker profile and genetic abnormalities in lobular carcinoma in situ

The predisposition of patients with lobular carcinoma in situ (LCIS) to develop invasive breast cancer (IBC) is well known. However, relatively little is known about the biologic characteristics, which may be involved in the development and progression of LCIS. This study evaluated 59 cases of LCIS (29 pure, 30 with synchronous IBC) for five biomarkers known to be important in IBC (ER, PgR, c-erbB-2, p53 and Ki-67 proliferation rate) by immunohistochemistry. A comprehensive analysis of loss-of-heterozygosity (LOH) was performed in 12 cases (10 pure, 2 with synchronous IBC) at 15 genetic loci on 9 chromosomes. LCIS demonstrated a low grade/favorable biophenotype that was not significantly different in cases with and without synchronous IBC (ER 98%, PgR 84%, c-erbB-24%, p53 19% and proliferation rate 2%). LOH was present in 80% of pure LCIS and the highest rates of LOH were at loci on 9p (30%), 16q (63%), 17p (33%) and 17q (50%). The clustering of LOH at these four foci suggests that inactivated tumor suppressor genes in these regions may be particularly important. LOH was present in both cases of LCIS with synchronous IBC and the LOH phenotype was shared by LCIS and IBC. Our findings suggest that five known prognostic factors in IBC do not have prognostic utility in LCIS. Multiple genetic mechanisms may be involved in the development of LCIS.

Biologic Properties of Columnar Epithelium Underneath Reepithelialized Squamous Mucosa in Barrett??s Esophagus

Chronic proton pump inhibitor (PPI) therapy may lead to partial regression of Barrett's esophagus (BE), resulting in the development of reepithelialized islands of squamous mucosa that may cover the underlying BE. The purpose of this study was to evaluate the clinical, histologic, and biologic characteristics of BE that is situated underneath squamous islands (BUSI). A total of 97 mucosal biopsies from 44 BE patients with BUSI were evaluated for a variety of histologic features (eg, type of epithelium, anatomic relationship of the underlying glands to the luminal surface, presence of adjacent mucosal glands or ducts, and the presence and degree of dysplasia), and immunostained for Ki-67, cyclin D1, and p53. BUSI was compared with adjacent areas of BE for all parameters. A clinical control group consisting of 50 BE patients without microscopic evidence of BUSI was selected for comparison of clinical and endoscopic features. The study group (34 males, 10 females; mean age, 67 years; mean length of BE, 5.5 cm) consisted of 27 (61%) and 12 (27%) patients on low- and high-dose PPI, respectively. On endoscopy, visible islands of squamous mucosa were noted in only 43% of study group patients (despite the presence of BUSI microscopically in all cases); one island was noted in 2%, multiple islands in 27%, and extensive islands in 14% of patients. The extent of squamous islands was unrelated to PPI dose. The study group was significantly more likely to have endoscopic evidence of extensive squamous islands compared with the control group (P = 0.009). Histologically, 89% of biopsies with BUSI showed intestinal-type, and 11% showed cardia-type, epithelium. Low- and high-grade dysplasia was noted in 4 (4%) and 5 (5%) biopsies, respectively. All patients with dysplasia in BUSI also showed dysplasia in other areas of the esophagus as well. Interestingly, BUSI reached the mucosal surface either by penetrating directly through, or by wrapping around, islands of squamous epithelium, in 68% of biopsies. Twenty-one percent of biopsies showed BUSI adjacent to submucosal glands or ducts. BUSI showed a significantly lower Ki-67 proliferation rate (29% vs. 49%, P < 0.001), and a lower, albeit nonsignificant, degree of cyclin D1 (16% vs. 29%) and p53 (4% vs. 17%) positivity in comparison to adjacent areas of BE. Furthermore, significantly lower proliferation rates were observed in BUSI that did not reveal an opening to the mucosal surface in comparison to foci that did. BUSI is phenotypically similar to typical surface BE but shows less severe proliferative abnormalities, particularly in buried glands that have no detectable connection to the esophageal lumen. Reduced proliferation may be due either to decreased exposure to luminal contents or to disruption of sloughing of surface epithelial cells into the crypt lumen. Prospective studies of large numbers of patients with BUSI will be required to determine the magnitude of its risk of progression to cancer.

Multiregional sampling reveals a homogenous distribution of Ki-67 proliferation rate in pituitary adenomas.

Ki-67 antigen is used as a marker of proliferative activity that is linked to growth rate, invasiveness and prognosis of pituitary adenomas. So far the distribution of Ki-67 index within an individual adenoma has not been investigated. If Ki-67 antigen expression differs significantly within an individual pituitary adenoma, a sampling error may result when assessing small fragments of adenoma tissue. Such a potential error would diminish the value of Ki-67 as a tool for postoperative patient management considerations. The aim of the present study was to assess Ki-67 proliferation rates in different regions of pituitary adenomas and to statistically analyse these data for potential regional differences within each tumor. Ki-67 proliferation index was assessed in smear preparations of 100 specimens of 26 consecutive patients operated on for pituitary adenoma in the Department of Neurosurgery, Medical University Vienna. Depending on the size and extent of the tumor, a mean of 4 tissue samples (range 2-8) was selected intraoperatively from each adenoma from endosellar, suprasellar, parasellar, and basal sellar dural locations. Overall mean cell proliferation rate measured by Ki-67 was 1.81 +/- 0.90% (range 0.33-3.43%). Histologically invasive adenomas had significantly higher mean Ki-67 proliferation index in all samples from the same tumor than non-invasive adenomas (2.01 +/- 0.91% vs. 1.11 +/- 0.59%; P = 0.024). Multiregional sampling revealed a homogenous distribution of Ki-67 index throughout an individual adenoma with no significant differences between any two different regions on t-test. Our data confirm that location of a biopsy does not influence Ki-67 index. Therefore, Ki-67 index of a single biopsy is representative for the whole individual adenoma. Thus Ki-67 index can be considered a reliable parameter for assessment of cell proliferation rate in adenoma biopsies and may be used for postoperative patient management considerations.

Expression of cell cycle-related gene products in different forms of primary versus recurrent PVNS

Expression patterns of cell cycle regulating gene products and Ki-67 in proliferating synovial cells of primary and recurrent pigmented villonodular synovitis (PVNS) in localized and diffuse lesions were examined by immunohistochemistry. Alterations of cell cycle-related proteins were seen in 98.7% of analyzed lesions. Both RB- and p53 pathways play a role in cell cycle dysregulation in PVNS. The RB pathway was more frequently altered in primary disease, while alterations of the p53 pathway seemed to be more important in recurrent lesions, regardless of the histomorphological type of disease. Ki-67 proliferation rate was elevated in recurrent tumors.