Close association between HER-2 amplification and overexpression in human tumors of non-breast origin.

The relationship between HER-2 overexpression and gene amplification is well evaluated in breast cancers but remains unclear or controversial in many other tumor entities. Therefore, we tested the HER-2 status in more than 120 different tumor entities. 5751 tumor samples were analyzed on TMAs by immunohistochemistry (Hercept-Test, DAKO) and fluorescence in situ hybridization (PathVysion, Abbott-Vysis) under highly standardized conditions. HER-2 overexpression (score 2/3+) and amplification occurred most often in breast cancers but was also seen in 18 other tumor entities including cancers of the urinary bladder (amplification in 14.3%, overexpression in 6.7%), stomach (8.3/4.9%), endometrium (6.6/6.8%), lung (2.8/3.1%) and ovary (2.3/1.2%). Remarkably, a strong association between overexpression and amplification was seen in all examined cancer entities. Trastuzumab therapy is highly efficient in HER-2 amplified breast cancer both in metastatic disease and as an adjuvant therapy. A variety of other tumor entities including frequent neoplasms and cancers with often limited therapeutic options have similar patterns of HER-2 alterations as observed in breast cancer (ie high overexpression due to high level gene amplification). Such tumor entities should be carefully evaluated for a possible utility of trastuzumab treatment.

Prognostic value of cell cycle and apoptosis regulatory proteins in mismatch repair-proficient colorectal cancer: a tissue microarray-based approach.

Cell cycle and apoptosis regulatory proteins are markers of tumor progression in colorectal cancer. In a series of 1,274 mismatch repair-proficient colorectal cancers, immunohistochemical analysis of p21, p27, p53, and bcl-2 expression was performed using the tissue microarray technique. In univariate analysis, p21 expression was associated with tumor location and pN0; p27 expression with tumor location, lower tumor grade, early pT, and pN; p53 expression with tumor location; and bcl-2 with early pT and pN. Expression of p27 identified subgroups with worse prognosis in pT3 N0 and pT3 N+ patients. None of the 4 tumor markers were independent prognostic indicators of survival. The multimarker phenotypes p21/p27/p53 and p21/p27/bcl-2 were associated with survival. In mismatch repair-proficient colorectal cancer, p27 expression is associated with a better prognosis, and pT, pN, and vascular invasion are independent prognostic factors. In addition, multimarker phenotypes are useful to identify colorectal cancer subgroups with different prognoses.

Tissue microarrays for comparing molecular features with proliferation activity in breast cancer.

Tissue microarrays (TMAs) are potentially suited to find associations between molecular features and clinical outcome. Enhanced cell proliferation, as measured by Ki67 immunohistochemistry, is related to poor patient prognosis in many different tumor types. Ki67 expression shows considerable intratumoral heterogeneity. It is unclear if the TMA format is suitable for the analysis of potentially heterogeneous markers because of the small size of TMA spots. We have analyzed a breast cancer TMA containing 2,517 breast tissues, including 2,222 neoplastic and 295 normal or premalignant samples, for Ki67 labeling index (Ki67 LI) and additional markers with a known relationship to Ki67 LI by immunohistochemistry (ER, PR, Bcl-2, Egfr, p16, p53) and Fluorescence in situ hybridization (HER2, MDM2, CCND1, MYC). A high Ki67 LI was linked to tumor phenotype including grade (p < 0.0001), stage (p < 0.0001), nodal stage (p = 0.0018), and patient prognosis (p < 0.0001), elevated protein levels of p53, p16 and Egfr, reduced levels of Bcl2, ER, and PR (p < 0.0001 each), as well as amplifications of HER2, MYC, CCND1 and MDM2 (p < 0.0001 each). In summary, all expected associations between Ki67 and the analyzed molecular markers could be reproduced with high statistical significance using a TMA containing only one tissue sample per tumor, measuring 0.6 mm in diameter. We conclude that associations with cell proliferation can be reliably analyzed in a TMA format.

EphB2 expression across 138 human tumor types in a tissue microarray: high levels of expression in gastrointestinal cancers.

PURPOSE: To comprehensively evaluate ephrin receptor B2 (EphB2) expression in normal and neoplastic tissues. EphB2 is a tyrosine kinase recently implicated in the deregulation of cell-to-cell communication in many tumors. EXPERIMENTAL DESIGN: EphB2 protein expression was analyzed by immunohistochemistry on tissue microarrays that included 76 different normal tissues, >4,000 samples from 138 different cancer types, and 1,476 samples of colon cancer with clinical follow-up data. RESULTS: We found most prominent EphB2 expression in the intestinal epithelium (colonic crypts) with cancer of the colorectum displaying the highest EphB2 positivity of all tumors. Positivity was found in 100% of 118 colon adenomas but in 33.3% of 45 colon carcinomas. EphB2 expression was also observed in 75 tumor categories, including serous carcinoma of the endometrium (34.8%), adenocarcinoma of the esophagus (33.3%), intestinal adenocarcinoma of the stomach (30.2%), and adenocarcinoma of the small intestine (70%). The occasional finding of strong EphB2 positivity in tumors without EphB2 positivity in the corresponding normal cells [adenocarcinoma of the lung (4%) and pancreas (2.2%)] suggests that deregulation of EphB2 signaling may involve up-regulation of the protein expression. In colon carcinoma, loss of EphB2 expression was associated with advanced stage (P < 0.0001) and was an indicator of poor overall survival (P = 0.0098). CONCLUSIONS: Our results provide an overview on the EphB2 protein expression in normal and neoplastic tissues. Deregulated EphB2 expression may play a role in several cancer types with loss of EphB2 expression serving as an indicator of the possible pathogenetic role of EphB2 signaling in the maintenance of tissue architecture of colon epithelium.

Cytokine expression in healthy and inflamed mucosa: probing the role of eosinophils in the digestive tract.

BACKGROUND: In eosinophilic esophagitis (EE), the esophagus is infiltrated with activated eosinophils that often evoke tissue damage, but the intestines of these patients remain unaffected. We thus hypothesized that different tissue-dwelling eosinophil populations may coexist: activated eosinophils that infiltrate the esophagus and resting eosinophils that reside in unaffected intestines. We sought to characterize different eosinophil subpopulations by comparing the expression of certain proinflammatory proteins in tissue-dwelling eosinophils at different parts of the gastrointestinal tract. METHODS: The 8 patients participating included 6 men and 2 women with a previously confirmed diagnosis of EE, whose average age was 39.4 years (range, 20-55 yr) and average disease duration was 13.6 years (range, 2-26 yr). Controls were 3 men and 1 woman, with a mean age of 43.3 years (range, 29-56 yr) with untreated functional dyspepsia who underwent diagnostic esophagogastroduodenoscopy. Six additional individuals having normal blood eosinophils were recruited for cytokine measurements in blood eosinophils. Immunofluorescence and immunoassays charted expression of CD25 and the TH2 cytokines, interleukin (IL)-4, IL-5, IL-10, and IL-13, in esophageal, intestinal, and blood eosinophils from controls and patients. RESULTS: Controls showed a small but significant proportion of intestinal, but no blood, eosinophils expressing CD25 and IL-13, suggesting physiologic activation occurring in the digestive tract. On the other hand, eosinophils infiltrating the inflamed esophageal mucosa of patients with EE showed strong evidence of activation, with most expressing CD25, IL-4, and IL-13. Moreover, IL-13-positive intestinal eosinophils were increased in patients compared with controls. CONCLUSIONS: We thus conclude that tissue-dwelling eosinophils show different and distinct cytokine expression patterns under noninflammatory and inflammatory conditions.

Predominance of high-grade pathway in breast cancer development of Middle East women.

Recent data have suggested considerable molecular differences in cancers from various ethnical groups. As molecular features are increasingly used for predicting cancer prognosis and response to therapy, better knowledge of ethnic molecular features is important. To identify potential molecular differences between breast cancers in Europe and the Middle East, we analyzed consecutive breast cancer series from Switzerland (n=2197) and Saudi Arabia (n=204). Tissue microarrays were analyzed by fluorescence in situ hybridization for HER2, CCND1, MYC, and EGFR amplification. The data revealed marked differences between Saudi and Swiss patients. Saudi breast cancers had a markedly higher frequency of HER2 (31 vs 17%; P<0.0001) and MYC (16 vs 5%; P<0.0001) amplifications than Swiss breast cancers. Remarkably, this was partly due to a much higher incidence of grade 3 cancers in the Saudi than in the Swiss population (65 vs 32%; P<0.0001). However, differences in amplification frequency hold also true within grade 3 cancers (HER2: 40 vs 30%, P<0.05; MYC: 22 vs 11%, P=0.002). Interestingly, in combination with known age standardized incidence rates of breast cancer in Saudi Arabia (21.6/100 000) and Switzerland (70.1/100 000), these data suggest that the incidence of high-grade breast cancer is comparable for Saudi and Swiss women, while the incidence of low-grade breast cancers is about 14 times lower in Saudi than for Swiss women. These observations suggest that a difference in genetic susceptibility and/or lifestyle between Saudi and Swiss women has a substantial and much higher than expected impact on the risk of low-grade breast cancer.

Prognostic relevance of gene amplifications and coamplifications in breast cancer.

Multiple different oncogenes have been described previously to be amplified in breast cancer including HER2, EGFR, MYC, CCND1, and MDM2. Gene amplification results in oncogene overexpression but may also serve as an indicator of genomic instability. As such, presence of one or several gene amplifications may have prognostic significance. To assess the prognostic importance of amplifications and coamplifications of HER2, EGFR, MYC, CCND1, and MDM2 in breast cancer, we analyzed a breast cancer tissue microarray containing samples from 2197 cancers with follow-up information. Fluorescence in situ hybridizations revealed amplifications of CCND1 in 20.1%, HER2 in 17.3%, MDM2 in 5.7%, MYC in 5.3%, and EGFR in 0.8% of the tumors. All gene amplifications were significantly associated with high grade. HER2 (P < 0.001) and MYC amplification (P < 0.001) were also linked to shortened survival. In case of HER2, this was independent of grade, pT, and pN categories. MYC amplification was almost 3 times more frequent in medullary cancer (15.9%), than in the histologic subtype with the second highest frequency (ductal; 5.6%; P = 0.0046). HER2 and MYC amplification were associated with estrogen receptor/progesterone receptor negativity (P < 0.001) whereas CCND1 amplification was linked to estrogen receptor/progesterone receptor positivity (P < 0.001). Coamplifications were more prevalent than expected based on the individual frequencies. Coamplifications of one or several other oncogenes occurred in 29.6% of CCND1, 43% of HER2, 55.7% of MDM2, 65% of MYC, and 72.8% of EGFR-amplified cancers. HER2/MYC-coamplified cancers had a worse prognosis than tumors with only one of these amplifications. Furthermore, a gradual decrease of survival was observed with increasing number of amplifications. In conclusion, these data support a major prognostic impact of genomic instability as determined by a broad gene amplification survey in breast cancer.

HER2 analysis in breast cancer: reduced immunoreactivity in FISH non-informative cancer biopsies.

Due to the central role in predicting response to herceptin and possibly also other anticancer drugs, accurate and reproducible detection of the HER2 status is important. Fluorescence in situ hybridization (FISH) and immunohistochemistry (IHC) are the most commonly used methods for HER2 analysis. It is a disadvantage of FISH that a fraction of cases remain not interpretable probably due to suboptimal tissue handling before analysis. To investigate a possible influence of tissue damage on the results of HER2 IHC we compared the HER2 IHC results obtained in tumors with and without interpretable FISH in a breast cancer tissue microarray. The HER2 IHC results differed greatly between 1551 tumors with interpretable HER2 FISH signals and 405 breast cancers showing no FISH signals. FISH informative tumors had an IHC score of 3+ in 12.6%, 2+ in 3% and 1+ in 9.2% of cases. FISH non-informative tumors showed significantly lower IHC scores (p < 0.0001). They were IHC 3+ in 3.9%, 2+ in 3.7% and 1+ in 4.4% of cases. Overall, the data show that not only FISH but also IHC results are dependent on good tissue quality for successful analysis. Poor tissue quality can be easily identified in FISH analyses because of a lack of hybridization signals. Inappropriate tissue handling is more dangerous in IHC because an artificial lack of staining can be regarded as 'negative' result.

High Ep-CAM expression is associated with poor prognosis in node-positive breast cancer.

Previous studies in small series of patients with invasive breast cancer suggested a prognostic value of Ep-CAM overexpression in primary tumor tissue. To corroborate these findings, we performed a retrospective analysis of Ep-CAM expression using a tissue microarray containing tissue specimens from a large patient set. Ep-CAM expression was evaluated by immunohistochemistry in breast cancer tissue from 1715 patients with documented raw survival data. High level Ep-CAM expression (overexpression) was found in 41.7% of tumor samples, low level expression was found in 48.0% and no expression in 10.3% of tumor samples. Ep-CAM expression predicted poor overall survival in this patient cohort (p < 0.0001). Overall survival decreased significantly with increasing Ep-CAM expression. However, in this patient sample Ep-CAM expression was not an independent prognostic marker by multivariate analysis. Subgroup analysis revealed that Ep-CAM expression was a prognostic marker in node-positive (p < 0.0001) but not in node-negative (p = 0.58) breast cancer patients. Intriguingly, Ep-CAM expression was predictive for a dismal prognosis in patients receiving adjuvant cytotoxic (p = 0.03) or hormonal therapy (p < 0.0001) but not in untreated patients (p = 0.41). In summary, this study provides strong evidence that expression of Ep-CAM is a powerful marker of poor prognosis in node-positive invasive breast carcinoma and a potential predictive marker of sensitivity to adjuvant hormonal and/or cytotoxic treatment modalities.

Eosinophilic esophagitis: red on microscopy, white on endoscopy.

BACKGROUND/AIMS: The presenting symptom of eosinophilic esophagitis, a chronic T(H)2-type inflammatory disease, is uniform dysphagia attacks. Histology reveals a dense mucosal infiltration with eosinophils. Unfortunately, endoscopic findings are often unremarkable or misleading. This study characterizes the endoscopic manifestations of eosinophilic esophagitis and analyzes the nature and clinical features of the frequently observed white alterations. METHODS: Thirty adult patients (22 males, 8 females; mean age 40.6 years) with previously confirmed EE prospectively underwent a structured interview, physical examination, laboratory tests and upper endoscopy with histomorphometric examination of the esophageal mucosa. RESULTS: On endoscopy, all patients showed mucosal abnormalities in the esophagus. Findings included an unspectacular loss of vascular pattern (93.3%) and white exudates (53.3%). Biopsies demonstrated significantly increased eosinophilia in the white exudates (108.4 vs. 14.0 cells/hpf). A significant correlation was found between white exudates and dysphagia frequency (<1 attack/week = 20%; >1 attack/week = 70%). CONCLUSION: Eosinophilic esophagitis evokes at least 12 different signs resulting in an individually unique endoscopic pattern, but no disease-specific picture. White exudates correspond to foci of dense eosinophilic infiltration reflecting inflammatory activity and are associated with significantly more frequent dysphagia attacks. Both the lack of a typical endoscopic picture as well as the heterogeneity of the eosinophilic infiltration impede diagnosis.

The homeobox intestinal differentiation factor CDX2 is selectively expressed in gastrointestinal adenocarcinomas.

CDX2 is a homeobox domain-containing transcription factor that is important in the development and differentiation of the intestines. Based on recent studies, CDX2 expression is immunohistochemically detectable in normal colonic enterocytes and is retained in most, but not all, colorectal adenocarcinomas. CDX2 expression has also been documented in a subset of adenocarcinomas arising in the stomach, esophagus and ovary. In this study, we examined CDX2 expression in a series of large tissue microarrays representing 4652 samples of normal and neoplastic tissues. Strong nuclear staining for CDX2 was observed in 97.9% of 140 colonic adenomas, 85.7% of 1109 colonic adenocarcinomas overall and 81.8% of 55 mucinous variants. There was no significant difference in the staining of well-differentiated (96%) and moderately differentiated tumors (90.8%, P=0.18), but poorly differentiated tumors showed reduced overall expression (56.0%, P<0.000001). Correspondingly, there was an inverse correlation between CDX2 expression and tumor stage, with a significant decrease in staining between pT2 and pT3 tumors (95.8 vs 89.0%, P<0.012), and between pT3 and pT4 tumors (89.0 vs 79.8%, P<0.016). Analysis of 140 locally advanced, CDX2-positive colorectal adenocarcinomas coarrayed with their matching lymph node metastases revealed that expression of this marker was retained in 82.1% of the metastases. Consistent with previous reports, CDX2 staining was observed in gastric adenocarcinomas (n=71), more commonly in the intestinal-type than the diffuse-type (28.9 vs 11.5%, P<0.05). Occasional ovarian carcinomas were positive for CDX2, including mucinous (10.5%), endometrioid (9.3%) and serous variants (2%), but expression was either very rare or absent in primary carcinomas of the lung, breast, thyroid, pancreas, liver, gallbladder, kidney, endometrium and urinary bladder. A low frequency of CDX2 expression in pancreatic and biliary carcinomas observed on the microarrays was pursued further by comparing these tumors with ampullary adenocarcinomas on conventional sections. Ampullary adenocarcinomas were more commonly positive for CDX2 (19/24, 79%) than cholangiocarcinomas (1/11, 9%) and pancreatic carcinomas (3/20, 15%). In summary, CDX2 is a sensitive and specific marker for colorectal adenocarcinoma, although its expression is decreased among higher grade and stage tumors, and it is not invariably present in metastases from positive primaries. CDX2 may also be helpful in distinguishing adenocarcinomas of the ampulla from those arising in the pancreas and biliary tree.

KIT (CD117)-positive breast cancers are infrequent and lack KIT gene mutations.

PURPOSE: KIT (CD117) is a transmembrane tyrosine kinase representing a target for STI571 (Glivec) therapy. Some KIT-overexpressing solid tumors have responded favorably to STI571, potentially because of the presence of KIT-activating mutations. EXPERIMENTAL DESIGN: To investigate the epidemiology of KIT overexpression and mutations, we investigated a series of 1654 breast cancers. All tumors were analyzed by immunohistochemistry in a tissue microarray format. RESULTS: KIT expression was always present in normal breast epithelium. However, cancer analysis revealed the only 43 of 1654 (2.6%) tumors were KIT-positive. KIT expression was more frequent in medullary cancer (9 of 47 positive; 19.1%) than in any other histological tumor subtype (P < 0.001). KIT expression was significantly associated with high tumor grade (P < 0.0001) but unrelated to pT and pN categories or patient survival. Mutation analysis of exons 2, 8, 9, 11, 13, and 17 was negative in 10 KIT-positive tumors. CONCLUSIONS: Overall, our data show that a high level of KIT expression occurs infrequently in breast cancer. KIT-positive breast cancers may not reflect "KIT up-regulation" because KIT is also expressed in normal breast epithelium. The lack of KIT mutations also argues against the therapeutic efficacy of STI571 in breast cancer.

Fragility of the esophageal mucosa: a pathognomonic endoscopic sign of primary eosinophilic esophagitis?

BACKGROUND: Primary eosinophilic esophagitis, a chronic inflammatory disorder of the esophagus, evokes recurrent dysphagia. Endoscopy is often unremarkable, and no consensus exists regarding management of resultant dysphagia. The response of a series of patients with primary eosinophilic esophagitis to dilation is reported together with a description of a possibly pathognomonic sign: fragile esophageal mucosa, for which the term "crêpe-paper" mucosa is introduced. METHODS: Five men underwent endoscopy because of dysphagia confirmed (clinically, endoscopically, and histologically) to be caused by primary eosinophilic esophagitis and were treated by bouginage. OBSERVATIONS: All patients had extremely fragile, inelastic, and delicate mucosa, which tore easily even with minor trauma. After the procedure, patients remained asymptomatic for 3 to 24 months. CONCLUSIONS: Primary eosinophilic esophagitis is characterized by fragile esophageal mucosa that readily tears in response to minor trauma during otherwise uneventful diagnostic endoscopy. This "crêpe-paper" sign may alert endoscopists to the presence of the disease when other mucosal alterations are lacking. Dilation is effective for patients with symptoms with minimal morbidity, despite development of disquieting lesions in response to the procedure.

Natural history of primary eosinophilic esophagitis: a follow-up of 30 adult patients for up to 11.5 years.

BACKGROUND & AIMS: Primary eosinophilic esophagitis is a chronic, increasingly recognized, interleukin 5-driven inflammatory disorder of the esophagus. The leading symptom in adults is uniform attacks of dysphagia, and the established histologic sign is a dense eosinophilic infiltration of the esophageal epithelium. Before this study, the natural course of eosinophilic esophagitis had not been defined and information regarding potential long-term risks was lacking. METHODS: This prospective case series included 30 adult patients with eosinophilic esophagitis (22 men and 8 women; mean age, 40.6 years) whose diagnosis had been made >1 year before study debut based on typical history, consistent endoscopic abnormalities, and infiltration of the esophageal epithelium with >24 eosinophils/high-power field. After a mean of 7.2 years, patients underwent a comprehensive follow-up examination. RESULTS: All patients survived the study period in good health and stable nutritional state. Dysphagia persisted in 29 patients, exerting a major negative effect on socioprofessional activities on 1 patient and a minor impact on 15. Attacks of dysphagia were more frequent in patients with blood eosinophilia or pronounced endoscopic alterations. The esophageal eosinophilic infiltration persisted in all symptomatic patients, but cell numbers spontaneously decreased significantly (78.7 vs. 40.3 cells/high-power field). The inflammatory process evoked fibrosis of the esophageal lamina propria but did not spread to the stomach or duodenum. No case evolved to a hypereosinophilic syndrome. CONCLUSIONS: Eosinophilic esophagitis, a primary and chronic disease restricted to the esophagus, leads to persistent dysphagia and structural esophageal alterations but does not impact the nutritional state. To date, no malignant potential has been associated with this disease.