HER2 Expression In Gastric Cancer Research Articles

Predicting human epidermal growth factor receptor 2 status of patients with gastric cancer by computed tomography and clinical features.

There have been no studies on predicting human epidermal growth factor receptor 2 (HER2) status in patients with resectable gastric cancer (GC) in the neoadjuvant and perioperative settings. We aimed to investigate the use of preoperative contrast-enhanced computed tomography (CECT) imaging features combined with clinical characteristics for predicting HER2 expression in GC. We retrospectively enrolled 301 patients with GC who underwent curative resection and preoperative CECT. HER2 status was confirmed by postoperative immunohistochemical analysis with or without fluorescence in situ hybridization. A prediction model was developed using CECT imaging features and clinical characteristics that were independently associated with HER2 status using multivariate logistic regression analysis. Receiver operating characteristic curves were constructed and the performance of the prediction model was evaluated. The bootstrap method was used for internal validation. Three CECT imaging features and one serum tumor marker were independently associated with HER2 status in GC: enhancement ratio in the arterial phase (odds ratio [OR] = 4.535; 95% confidence interval [CI], 2.220-9.264), intratumoral necrosis (OR = 2.64; 95% CI, 1.180-5.258), tumor margin (OR = 3.773; 95% CI, 1.968-7.235), and cancer antigen 125 (CA125) level (OR = 5.551; 95% CI, 1.361-22.651). A prediction model derived from these variables showed an area under the receiver operating characteristic curve of 0.802 (95% CI, 0.740-0.864) for predicting HER2 status in GC. The established model was stable, and the parameters were accurately estimated. Enhancement ratio in the arterial phase, intratumoral necrosis, tumor margin, and CA125 levels were independently associated with HER2 status in GC. The prediction model derived from these factors may be used preoperatively to estimate HER2 status in GC and guide clinical treatment.

The effect of specimen processing time on HER2 expression in gastric cancer and esophagogastric junction cancer: a single-center retrospective observational study

BackgroundRecent developments in the field of companion diagnosis and molecular-targeting therapeutic agents have helped in developing treatments targeting human epidermal growth factor receptor 2 (HER2) in gastric cancer (GC) and esophagogastric junction cancer (EGJC), and the importance of accurate diagnosis of HER2 expression is increasing. However, the HER2-positivity rate significantly differs among reports in GC and EGJC, and factors that affect HER2-positivity require elucidation.MethodsThe present study retrospectively examined factors related to HER2-positivity in a single institution, including age, sex, body mass index, the American Society of Anesthesiologists physical status, tumor information, and surgery information, including time to specimen processing.ResultsOur study included 165 patients tested for HER2 using GC and EGJC surgery specimens among the 1,320 patients who underwent gastrectomy from January 2007 to June 2022. In total, 35 (21.2%) and 130 (78.8%) patients were HER2-positive and -negative, respectively. Multivariate analysis revealed that intestinal type (odds ratio [OR]: 3.41, 95% confidence interval [CI]: 1.44–8.09, p = 0.005), pM1 (OR: 3.99, 95% CI: 1.51–10.55, p = 0.005), and time to specimen processing of < 120 min (OR: 2.65, 95% CI: 1.01–6.98, p = 0.049) were independent factors that affected HER2-positivity.ConclusionsThe outcomes of the present study indicated that intestinal type, pM, and time to specimen processing are important factors affecting HER2-positive rates in GC and EGJC. Therefore, the risk of false-negative HER2 results may be reduced by decreasing the time required to process the resected specimen. Additionally, accurate diagnosis of HER2 expression may increase the opportunity to administer molecular-targeted drugs that can expect therapeutic effects to patients appropriately.Trail registrationRetrospectively registered.

Analysis of HER2 protein expression and clinical prognosis based on CT texture analysis in the arterial phase of gastric cancer

ObjectiveTo assess the relationship of CT texture feature parameters in the arterial phase of gastric cancer with the expression of HER2 protein. MethodsA total of 39 patients with gastric cancer confirmed by pathology were included and further divided into the HER2 negative and positive groups. According to tumor invasion depth, they were assigned to the early and advanced groups. The maximum diameter of the tumor lesions on the CT axial plane was measured, and 3-year survival was followed up and recorded. ResultsThe maximum axial diameter of early gastric cancer was 4.84 ± 0.52 cm, and the 3-year follow-up survival time was 2.41 ± 0.56 years; the maximum diameter of advanced gastric cancer was 6.58 ± 0.42 cm, and the 3-year follow-up survival time was 1.21 ± 0.21 years with a significance between them (P < 0.05). The CT texture parameters in the arterial phase elucidated significant differences in the 10th percentile, 90th percentile, maximum, median, average, and minimum value between HER2 positive group and negative group (P < 0.05) without difference in texture features between the two groups (P > 0.05). ROC curve showed when the 10th percentile was 13.5, the 90th percentile was 70.2, the maximum value was 101.5, the median was 24.2, the average was 39.4, and the minimum of −7 was the best cut-off value. The specificity and sensitivity for distinguishing HER2-negative or positive were high, and the area under curve (AUC) was about 0.707–0.813, of which the 90th percentile was the most significant. ConclusionThe maximum diameter of the tumor in the CT axial plane is related to early and advanced gastric cancer and the prognosis. Based on CT arterial phase texture parameters, HER2 expression in gastric cancer can be judged to provide a basis for clinical diagnosis and treatment.

Correlations of 18F-FDG PET/CT Metabolic Parameters and Metabolic Heterogeneity with Human Epidermal Growth Factor Receptor 2 Expression in Patients with Gastric Cancer

Objective To investigate the value of 18F-FDG PET/CT metabolic parameters and metabolic heterogeneity for predicting the expression of human epidermal growth factor receptor 2 (HER2) in patients with gastric cancer. Methods A total of 45 patients with gastric cancer confirmed by surgical pathology between September 2016 and May 2021 were enrolled in this study.All the patients underwent 18F-FDG PET/CT examination before surgery.The maximum standardized uptake value (SUVmax),metabolic tumor volume (MTV),and total lesion glycolysis (TLG) of primary gastric cancer were measured,and the linear regression slope of MTV corresponding to different SUVmax thresholds (40% SUVmax and 80% SUVmax) was calculated.The absolute value of the slope was deemed to represent the metabolic heterogeneity of primary gastric cancer,termed the heterogeneity index (HI).Univariate and multivariate Logistic regression analyses were conducted to evaluate the correlations of 18F-FDG PET/CT metabolic parameters and HI with HER2 expression. Results The 45 patients included 10 with positive HER2 expression and 35 with negative result.The MTV (P=0.043) and HI (P=0.048) were lower in the patients with positive HER2 expression than in the patients with negative HER2 expression.The MTV and HI had the optimal thresholds of 12.10 cm3 and 3.71,respectively,which respectively showed the accuracy of 62.2% and 57.8% for predicting HER2 expression.The univariate Logistic regression showed that the tumor differentiation degree,MTV,and HI were correlated with HER2 expression,while the multivariate Logistic regression showed that only the tumor differentiation degree (OR=20.130,95%CI=1.843-219.860,P=0.014) was an independent predictor for HER2 expression.A further stratified analysis of the tumor differentiation degree showed that HER2 expression only varied among different MTV threshold groups in patients with moderately/well differentiated gastric cancer (P=0.031). Conclusions MTV and HI were associated with HER2 expression in gastric cancer,whereas neither played an independent predictive role.Therefore,these factors should be combined with clinicopathological characteristics of patients to jointly guide treatment decisions.

Clinicopathologic significance of Her-2 and P53 expressions in gastric cancer

BackgroundTo detect the expression of HER-2 and P53 patients with gastric cancer and to analyze their correlation. MethodsA total of 249 gastric cancer patients with complete clinical data who received surgical treatment from China–Japan Union Hospital of Jilin University were selected. The expression of Her-2 and P53 were detected by immunohistochemistry using the streptavidin-biotin-peroxidase method. The correlations between HER-2 and P53 in gastric cancer were analyzed. ResultsThe positive rate of Her-2 and P53 expression was 37.3% (93/249) and 100% in all the specimens, respectively. The intensity of Her-2 expression was significantly different in patients with different degrees of gastric cancer cell differentiation (P = 0.012). Meanwhile, the expression of her-2 was closely related to whether the pathological type of gastric cancer was a signet-ring cell carcinoma (P = 0.022). Different percentage of positive P53 expression was closely related to the grade of tumor differentiation (P = 0.035) and positive Ki67 expression (P = 0.001). There was a significant positive correlation between HER-2 and P53 expression in gastric cancer (P = 0.003). These findings suggest that HER-2 and P53 have synergistic effects in gastric cancer. ConclusionHer-2 and P53 are important markers for invasion and metastasis of gastric cancer. Combined detection of P53 and Her-2 expression in gastric cancer tissue can be used to assess prognosis and screen cancer patients at high risk of metastasis.

1394P Frequentist and Bayesian analysis of second line treatment effectiveness in AGAMENON-SEOM gastric cancer registry

Real world data for second (2nd) line treatment and effectiveness depending on HER2 expression in gastric cancer are lacking. The objectives of this analysis were to evaluate 2nd line treatments effectiveness, and to explore HER2 expression potential effect on paclitaxel + ramucirumab (RAMUPACLI).

Prognostic Significance of HER-2 Expression in Gastric Cancer

In gastric cancers we purposed to examine the relationship between age, gender, invasion depth, lymph node metastasis,lymphovascular invasion, Lauren's classification, presence of perineural invasion and the expression of Human Epidermal GrowthReceptor (HER-2) by immunohistochemical (IHC) and dual-color silver-enhanced in situ hybridization (D-SISH) method. In our study,242 gastric resection materials that were studied HER-2 by IHC and/or D-SISH method referred to our department between January2014 and December 2017 for malignancy were included. The relationship between HER-2 expression rate and prognostic parameterswas investigated. No statistical relation was found between age and gender and HER-2 positivity in either method. No statisticallysignificant results were obtained between lymphovascular invasion, lymph node metastasis, presence of perineural invasion, depth ofinvasion and Lauren classification, and HER-2 positivity by immunohistochemical and D-SISH method. In our study, no statisticallysignificant results were obtained between important prognostic parameters and HER-2 positivity with either IHC or D-SISH method. In24.1% of the cases that were HER-2 positive by IHC, positivity was not observed with the D-SISH method. Also, 20.8% of the casesreported as immunohistochemically uncertain (equivocal) were seen as positive by the D-SISH method. Based on all these results, wewould like to state that HER-2 positivity / negativity determined by IHC can be changed by the D-SISH method. In addition, although itwas shown in our study that HER-2 has no prognostic significance in gastric carcinomas, it is reported in studies in the literature thatthe addition of Trastuzumab to chemotherapy increases survival. For this reason, we think that it would be more beneficial to applythe IHC and D SISH method together to obtain the true HER-2 result.

Intratumoral and intertumoral heterogeneity of HER2 immunohistochemical expression in gastric cancer

BackgroundGiven the high heterogeneity of tumor tissue in gastric cancer (GC), inaccurate detection of tumor biomarkers will inevitably hamper a precise diagnosis and selection of patients for targeted therapies. Human epidermal growth factor receptor 2 (HER2) has been widely accepted as an underlying treatment biomarker of GC. The objective of this study is to investigate the heterogeneity (both intratumoral and intertumoral) of HER2 expression in GC, and the relationship between heterogeneity and the clinicopathological features. MethodsA total of 618 patients with primary gastric adenocarcinoma were recruited, and two formalin-fixed paraffin-embedded (FFPE) tumor-containing blocks of each patient were selected for HER2 immunohistochemical (IHC) assay. Clinicopathological characteristics were recorded, and intratumoral and intertumoral heterogeneity of HER2 IHC expression was determined. ResultsThe results indicated that the dual-block assays significantly increased the HER2 overexpression (IHC 2+ and 3+) rate compared with the single paraffin block detection. Approximately 50 % of the cases showed intratumoral HER2 heterogeneity within a single tissue section, and 30.10 % of cases showed intertumoral heterogeneity between a patient’s two blocks. Furthermore, intertumoral heterogeneity was associated with tumors of small size (P = 0.029) and distal location (P = 0.032) characters, while the intratumoral heterogeneity was correlated with poorly differentiated carcinomas. Laurén’s diffuse type showed a notably higher intratumoral heterogeneity rate, and the mixed type exhibited higher intertumoral HER2 discordance between the dual-block cohorts (P < 0.001). Besides, HER2 heterogenous overexpression was not associated with age, gender, type of resection, lymphatic or venous invasion, perineural invasion or pTNM (P > 0.05) for both cohorts. ConclusionThe research findings in this paper indicate that the intratumoral and intertumoral heterogeneity of HER2 overexpression is common in GC patients, and these variations are associated with certain clinicopathological features. We highly recommend multi-block HER2 assessment for accurate diagnosis of GC.

CURRENT POINT OF VIEW ON PROGNOSTIC AND PREDICTIVE ROLES AND PRACTICAL APPLICATION OF HER2 RECEPTOR’S DETECTION. LITERATURE REVIEW

Human epidermal growth factor receptor HER2, a proto-oncogene involved in the proliferation and differentiation signaling pathway. The overexpression and amplification of the HER2 gene and their significance have been studied in breast cancer. Data on HER2 over expression in gastric cancer vary widely, and the value is presented by inconsistent disparate data. The interpretation of HER2 in gastric cancer differs from the evaluation in breast cancer. The purpose of this review is to summarize current data on the evaluation of HER2 in gastric cancer for the selection of targeted therapy. The search in modern databases of medical literature was carried out, more than 100 modern literary sources on the above-mentioned topic were studied and analyzed in detail and carefully. The most significant data on the evaluation of HER2 expression in gastric cancer and its prognostic and predictive value were selected and presented. Selected options evaluate the expression of HER2 receptor in operating and biopsy material of stomach cancer. Comparative data on the use of different antibody clones to solve the above problem are presented. The most frequent and important errors and possible interpretation disorders in the expression of HER2 in gastric cancer are analyzed. The use of transtuzumab for targeted therapy in gastric cancer makes it mandatory to test surgical and biopsy samples of gastric cancer to assess their expression of HER2. The development of various methods and the progress of molecular biology, however, the main role of the immunohistochemical method in solving this problem still left. Gastric cancer needs a single accessible standardized system for evaluating HER2 expression, and, most importantly, expert level interpretation of these results.

HER2 Expression in Gastric Cancer and Gastroesophageal Junction Cancer

Background: Carcinoma of the stomach is a major cause of cancer mortality worldwide. Due to social impact of gastric carcinoma (GC), there is a need to stratify patients into appropriate screening, surveillance and treatment programs. Although histopathology remains the most reliable and less expensive method, numerous efforts have been made to identify and validate novel biomarkers to accomplish the goals. In recent years, several molecules have been identified and tested for their clinical relevace in GC management. Among the biomarkers with the exception of HER2, none of the biomarkers is currently used in clinical practice, and some of them were described in single studies.&#x0D; Materials and Methods: This prospective type of observational study was performed in the Department of Surgery, Dhaka Medical College Hospital, Dhaka, 6 months from approval of protocol. Total 45 consecutive patients aged 18 years and above without consideration of gender were selected purposefully. Every patient was evaluated by clinical examination, appropriate investigations and after a confirm diagnosis of the tissue from the cancer. All patients have undergone operative intervention and Gastrectomy specimens were subtotal (including cardiac and pylorus), subtotal (including the pylorus), total radical gastrectomy and oesophago-gastrectomy sample. All specimens obtained were immersed in 10% formalin. Samples of whom were sent to the department of pathology, DMCH for histopathology examination. Portion of representative tissue/block was sent to AFIP (Armed Forces Institute of Pathology, Dhaka) for immunohistochemistry to find out the HER2 expression in gastric cancer and gastro-oesophageal cancer. Data was collected in a pre-designed questionnaire by face to face interview.&#x0D; Result and observation: In this study when 45 cases were categorized according to WHO grading system it was observed that majority (30) patients were found in grade II, among them 3(10%) were HER2 positive. But with grade III tumour the HER2 positivity were found more i,e; 37.5% (3/8). Grade- I tumor show HER2 neu expression 28.57% (2/7) and according to location most of the cases with HER2 positive expression was located in the gastro-esophageal junction which is 27.27% (3/11) than gastric carcinoma which is 14.70% (5/34).&#x0D; Conclusion: Most of the patients of gastric and gastrooesophageal junction adenocarcinoma are diagnosed at a very late stage, so they require special attention in treatment protocol, including chemotherapy and immunotherapy for increasing their survivability. The study showed with poorly differentiated (high grade) tumour, the HER2 positivity were found more.&#x0D; Journal of Surgical Sciences (2018) Vol. 22 (2) : 79-82

Loss of HER2 positivity after anti-HER2 chemotherapy in HER2-positive gastric cancer patients: results of the GASTric cancer HER2 reassessment study 3 (GASTHER3).

Although discordance in HER2 positivity between primary and metastatic lesions is well established, changes in HER2 positivity after anti-HER2 therapy have not been well evaluated in gastric cancer. We aimed to evaluate whether HER2 expression in gastric cancer is affected by trastuzumab therapy. We enrolled 48 HER2-positive advanced gastric cancer patients treated with trastuzumab-containing first-line chemotherapy and had paired biopsies at baseline and after progression. At baseline, HER2 was positive, with immunohistochemistry (IHC) 2+ and in situ hybridization (ISH)+ in five patients, and with IHC 3+ in 43 patients. Fourteen patients (29.1%) exhibited loss of HER2 positivity on post-progression biopsy: 10 with IHC 0 or 1+, and four with IHC 2+/ISH-. HER2 remained positive on second biopsy in 34 patients: four with IHC 2+/ISH+, and 30 with IHC 3+. Median H-scores decreased from 225 to 175 (p = 0.047). HER2 genetic heterogeneity was defined in one of 34 ISH-assessable patients (2.9%) at baseline and seven of 32 (21.9%) at second biopsy. Among 13 patients who received second-line trastuzumab emtansine, three showed HER2-negative conversion; they had no objective response and short progression-free survival (1.2, 1.3, and 3.4months). Patients with stable HER2 status had a 44% response rate and median progression-free survival of 2.7 (0.4-36.8)months. A substantial portion of HER2-positive patients showed HER2-negative conversion with increased HER2 genetic heterogeneity after failure of trastuzumab-containing chemotherapy. Loss of HER2 positivity could be predictive of second-line anti-HER2 treatment, suggesting a need to reexamine HER2 status before initiating second-line anti-HER2 therapy.

Noninvasive Detection of HER2 Expression in Gastric Cancer by 64Cu-NOTA-Trastuzumab in PDX Mouse Model and in Patients.

The purpose of this study was to establish the quality control and quantify the novel 64Cu-NOTA-Trastuzumab in gastric cancer patient-derived xenografts (PDX) mice models and patients by applying the molecular imaging technique. Trastuzumab was labeled with 64Cu using NCS-Bz-NOTA as bifunctional chelator, and hIgG1 was labeled with the same procedures as a negative control agent. HER2-positive (case 176, n = 12) and HER2-negative (case 168, n = 3) PDX models were established and validated by Western blot, DNA amplification, and immunohistochemistry (IHC). Both models were conducted for micro-PET imaging by tail injection of 18.5 MBq of 64Cu-NOTA-Trastuzumab or 64Cu-NOTA-hIgG1. Radioprobe uptake in tumor and main organs was quantified by region of interested (ROI) analysis of the micro-PET images and autoradiography. Finally, gastric cancer patients were enrolled in preliminary 64Cu-NOTA-Trastuzumab PET/CT scans. NOTA-Trastuzumab was efficiently radiolabeled with 64Cu over a 99% radiochemical purity and 17.5 GBq/μmol specific activity. The immune activity was preserved as the nonmodified antibody, and the radiopharmaceutical proved to be stable for up to 5 half-decay lives of 64Cu both in vitro and in vivo. Two serials of PDX gastric cancer models were successfully established: case 176 for HER2 positive and case 168 for HER2 negative. In micro-PET imaging studies, 64Cu-NOTA-Trastuzumab exhibits a significant higher tumor uptake (11.45 ± 0.42 ID%/g) compared with 64Cu-NOTA-IgG1 (3.25 ± 0.28 ID%/g, n = 5, p = 0.0004) at 36 h after intravenous injection. Lower level uptake of 64Cu-NOTA-Trastuzumab (6.35 ± 0.48 ID%/g) in HER2-negative PDX tumor models further confirmed specific binding of the radioprobe. Interestingly, the coinjection of 2.0 mg of Trastuzumab (15.52 ± 1.97 ID%/g) or 2.0 mg of hIgG1 (15.64 ± 3.54 ID%/g) increased the 64Cu-NOTA-Trastuzumab tumor uptake in PDX tumor (HER2+) models compared with 64Cu-NOTA-Trastuzumab alone ( p < 0.05) at 36 h postinjection. There were good correlations between micro-PET images and IHC ( n = 4) and autoradiography in PDX (HER2+) tumor tissues. Therefore, 64Cu-NOTA-Trastuzumab successfully translated to clinical PET imaging, and 64Cu-NOTA-Trastuzumab PET/CT scan in gastric cancer patients showed good detection ability. In conclusion, we reported quality control and application of novel 64Cu-NOTA-Trastuzumab for HER2 expression in PDX gastric cancer mice models and gastric cancer patients. Moreover, 64Cu-NOTA-Trastuzumab holds great potential for noninvasive PET detection, staging, and follow-up of HER2 expression in gastric cancer.

Abstract 2615: Heterogeneity of HER2 expression in gastric cancer (GC) leads to high deviation rates between local and central testing and hampers efficacy of anti-HER2 therapy: Survival results from the VARIANZ study

Abstract Background: HER2 is a membrane-bound receptor tyrosine kinase that belongs to the epidermal growth factor receptor family. The anti-HER2 directed monoclonal antibody trastuzumab is approved for 1st-line treatment of stage IV HER2+ GC, while other drugs addressing HER2 (pertuzumab, TDM1, lapatinib) failed to improved survival outcomes. Until today, resistance against HER2-directed treatment of GC is poorly understood. The VARIANZ study aims to assess the biologic background of resistance to anti-HER2 therapy in GC. Methods: This academic network study funded by the German Federal Ministry of Education and Research (BMBF 01ZX1610E) recruited patients (pts) who received medical treatment for stage IV GC in 34 sites. HER2 expression was verified centrally by two dedicated GI pathologists using immunohistochemistry (DCS, HI608C0I) and chromogenic in situ hybridization (Zytomed Systems, C-3022-40). Treatment and survival outcomes were reported by investigators. Results: 502 pts were enrolled from May 2014 to Oct 2017. At present, 442 samples were fully characterized for HER2. According to criteria from the ToGA study, 73 of 442 samples were found HER2+ in central testing. In 57 samples with a HER2+ status diagnosed by local pathologists, HER2 positivity could not be confirmed centrally. Deviation rate between local and central testing was 23%. Centrally confirmed HER2-positive GC displayed a higher percentage of tumor cells staining positive for HER2 (49.72 ± 28.58% [SD] vs. 11.35 ± 17.74% [SD]; p&amp;lt;0.001) and a higher HER2/CEP17 ratio (5.78 ± 2.55 [SD] vs. 1.43 ± 0.41 [SD]; p&amp;lt;0.001). Survival outcomes indicate that only pts with centrally confirmed HER2+ status benefit from trastuzumab with an overall survival of 30.7 months (95%-CI 10.7 - 50.8; n=28) versus 7.9 months (95%-CI 2.8 - 12.9, n=33); HR for death was 3.9 in pts with unconfirmed vs. confirmed HER2+ GC receiving trastuzumab plus chemotherapy; p&amp;lt;0.0001. Conclusions: Variability between local and central HER2 assessment in GC is significant. Pts with centrally unconfirmed HER2+ status have no benefit from anti-HER2 therapy. HER2 status should be assessed in highly qualified laboratories and cut-offs for defining HER2+ should be reconsidered. Alternative treatment options–other than trastuzumab–should be investigated in pts with unconfirmed or borderline HER2 expression. Citation Format: Florian Lordick, Ivonne Haffner, Birgit Luber, Dieter Maier, Elba Raimundez, Jan Hasenauer, Albrecht Kretzschmar, Ludwig Fischer von Weikersthal, Miriam Ahlborn, Jorge Riera Knorrenschild, Gabriele Siegler, Beate Rau, Stefan Fuxius, Thomas Decker, Katrin Schierle, Christian Wittekind. Heterogeneity of HER2 expression in gastric cancer (GC) leads to high deviation rates between local and central testing and hampers efficacy of anti-HER2 therapy: Survival results from the VARIANZ study [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2018; 2018 Apr 14-18; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2018;78(13 Suppl):Abstract nr 2615.

Correlation of Gli1 and HER2 expression in gastric cancer: Identification of novel target

HER2 becomes the standard of care for guiding adjuvant treatment of gastric cancer with trastuzumab in recent years. However, the usage of this target agent is still limited because of the resistance to trastuzumab or the negative expression of HER2 in tumor tissues. The Gli1 and HER2 both play an important role in the pathogenesis of gastric cancer. However, the correlation of them is still unclear. Here we found Gli1 and HER2 are highly expressed in gastric cancer tissues, and they are positively related. Next, we found Gli1 positive patients live a shorter survival time no matter HER2 positive or negative. Furthermore, univariate and multivariate analysis revealed that venous invasion, HER2 expression, Gli1 expression were independent prognostic factors for the survival time in gastric cancer. In addition, suppressing the expression level of Gli1 can decrease the cell viability and migration ability in cells and subcutaneous tumors. Finally, we found that HER2 may regulate Gli1 by Akt–mTOR–p70S6K pathway. Inhibit of HER2 and SMO have synergistic effect on reduction of cell viability. In conclusion, Gli1 is a favorable prognostic indicator in gastric cancer. As a novel target, Gli1 worth further study, especially in Her2-targeted therapy-resistant cancers.

Clinicopathological factors associated with HER2-positive gastric cancer: A meta-analysis.

Background:The treatment of patients with advanced gastric cancer remains a most challenging task in the clinical practice. Recently, targeted therapies have significantly impacted the treatment strategy for many common malignancies. The use of trastuzumab, a monoclonal antibody against human epidermal growth factor receptor 2 (HER2; also known as ERBB2), plus chemotherapy proved to improve median overall survival in patients with advanced gastric cancer, compared with chemotherapy alone in Trastuzumab for Gastric Cancer (ToGA) trial. However, the prognostic value of HER2 status in gastric cancer remains controversial. Therefore, the aim of this study was to investigate the clinical pathology significance of HER2 overexpression in resectable gastric cancer for selecting the right patients with gastric cancer who may benefit from trastuzumab treatment.Methods:Publications reported the clinicopathological factors associated with HER2 status in gastric cancer from 2012 to 2017 were collected. The literature databases, such as “Cochrane Library”, “Sciencedirect”, “Springer”, “PubMed”, “Embase”, were extensively searched to retrieve the clinical studies of HER2 expression in gastric cancer. The major outcomes measures were odds ratios (ORs) and their 95% CIs. Statistical analysis was carried out by Revman software 5.3. The Newcastle–Ottawa scale was used to assess the quality of evidence.Result:Fifteen studies met our inclusion criteria. This study demonstrated that the pooled OR for HER2 positivity was associated with being male (OR: 1.42; 95% CI: 1.23–1.64), well/moderately differentiated tumor (OR: 2.76; 95% CI: 1.72–4.45), and for intestinal-type tumor (OR: 0.31; 95% CI: 0.25–0.38). However, it had no correlation with depth of tumor (P = .07), venous invasion (P = .82), and lymphovascular invasion (P = .24).Conclusion:HER2-positive expression was associated with male gender, intestinal type, and well/moderate cell differentiation. We recommend that those gastric cancer patients who may benefit from trastuzumab treatment should be subjected to targeted therapies. However, detecting HER2 status may contribute to the target therapy for gastric carcinoma using trastuzumab. This would be strengthened by further studies incorporating comorbidity data, and outcomes from centralized programs.

Immunohistochemical assessment of HER2 expression in gastric cancer. A clinicopathologic study of 93 cases

Abstract Background Gastric cancer in Mexico is ranked third in both males and females. Most patients present clinically with advanced disease and treatment options are sparse. HER2 overexpression in gastric cancer is related to poor outcome. Immunohistochemical testing for HER2 is becoming the standard of care for guiding adjuvant treatment of gastric cancer with trastuzumab. Objectives To determine the frequency of HER2 overexpression in patients with gastric cancer in the Hospital de Oncologia del Centro Medico Nacional, Siglo XXI and its association with other histopathological findings. Material and methods Patients with gastric cancer who underwent surgery between March 12, 2006 and August 31, 2011, were enrolled in this retrospective study. Diagnosis was confirmed by review of slides and immunohistochemistry with anti-HER2 antibody was performed. Scoring was done by Hoffman scoring system. Medical records were evaluated. Results Ninety-three patients were included in the study, with 43 (46.2%) male and 50 (53.7%) female patients. The median age was 64 years. HER2-positive tumours were identified in 6 patients (6.45%) and located most frequently in the proximal stomach. There was no difference in HER2 overexpression in relation to age, gender or histologic type. Conclusion In our study, about 7% of patients with gastric cancer were HER2-positive on immunohistochemistry.

651P - Is there any relationship between Helicobacter pylori infection and HER2 expression in gastric cancer?

651P - Is there any relationship between Helicobacter pylori infection and HER2 expression in gastric cancer?

Central validation of HER2 status to determine heterogeneity of marker expression in HER2-positive gastric cancer (GC).

12 Background: 10-20% of GC overexpress HER2, a membrane-bound receptor tyrosine kinase (RTK) which belongs to the epidermal growth factor receptor (EGFR) family. Drugs directed against HER2 have shown mixed success in the treatment of advanced GC. While trastuzumab, a monoclonal antibody addressing HER2 has been approved for 1st-line treatment of stage IV HER2+ GC, trastuzumab-emtansine failed to improve outcomes in 2nd-line and lapatinib, a small molecular RTK inhibitor of HER2 and EGFR was not effective in 1st- and 2nd-line. Until now, primary and secondary resistance against HER2-directed treatment of GC is not well understood. The VARIANZ study aims to assess mechanisms influencing efficacy of trastuzumab in HER2+ GC. Methods: In this multicenter study, patients who receive medical treatment for advanced GC are recruited in 31 sites. The HER2 status is verified centrally by two dedicated GI pathologists using immunohistochemistry (IHC, DCS, HI608C0I) and chromogenic-in-situ hybridization (CISH, Zytomed Systems, C-3022-40). Results: From May 2014 to August 2016, we have enrolled 316 patients in this ongoing project (72% male, median age 64 years). At present, 281 samples were fully characterized for the HER2 status. According to criteria from the Trastuzumab for Gastric Cancer (ToGA) study, 53 of 281 samples were characterized HER2+ by central testing. In 38 samples that were diagnosed as HER2+ by local pathologists the HER2 status could not be verified centrally. 7 HER2- probes in local testing were characterized as HER2+ by central testing. The overall deviation rate between local and central testing is 27%. HER2 gene amplification in HER2+ tumors with deviating local report (mean HER2/CEP17: 2.8 ± 0.9, range between 1.9 and 4.5) is lower compared to HER2+ tumors and confirmed local report (mean HER2/CEP17: 5.5 ± 2.6; range between 2.2 and 11.0; p = 0.014). Conclusions: HER2-expression in GC is heterogeneous and still not easy to assess. Variability between local and central HER2 assessment is significant. Robust biomarkers predicting response or resistance to HER2 and other target therapies are needed. Clinical trial information: NCT02305043.

Epidemiologic Study of Human Epidermal Growth Factor Receptor 2 Expression in Advanced/Metastatic Gastric Cancer: an Assessment of Human Epidermal Growth Factor Receptor 2 Status in Tumor Tissue Samples of Gastric and Gastro-Esophageal Junction Cancer.

PurposeThe Trastuzumab for gastric cancer (GC) trial identified human epidermal growth factor receptor 2 (HER2) as a predictor of successful treatment with trastuzumab (HER2 receptor targeting agent) among patients with advanced/metastatic GC. To date, the prevalence of HER2 overexpression in the Korean population is unknown. The present study aimed to assess the incidence of HER2 positivity among GC and gastroesophageal (GE) junction cancer samples and the relationship between HER2 overexpression and clinicopathological characteristics in Korean patients.Materials and MethodsTumor samples collected from 1,695 patients with histologically proven GC or GE junction enrolled at 14 different hospitals in Korea were examined. After gathering clinicopathological data of all patients, HER2 status was assessed by immunohistochemistry (IHC) at each hospital, and IHC 2+ cases were subjected to silver-enhanced in situ hybridization at 3 central laboratories.ResultsA total of 182 specimens tested positive for HER2, whereas 1,505 tested negative. Therefore, the overall HER2-positive rate in this study was 10.8% (95% confidence interval=9.3%–12.3%). The HER2-positive rate was higher among intestinal-type cases (17.6%) than among other types, and was higher among patients older than 70 years and 50 years of age, compared to other age groups.ConclusionsOur evaluation of the HER2 positivity rate (10.8%) among Korean patients with GC and GE junction indicated the necessity of epidemiological data when conducting studies related to HER2 expression in GC and GE junction.

PD-L1 and HER2 expression in gastric cancer (GC) patients (pts) using cell-free RNA (cfRNA).

e15539Background: In clinical practice, the majority of tumor biology information comes from an initial specimen. The ability to assess changes across time can direct treatment selection. Liquid bi...