A retrospective comparison of S-1 plus cisplatin and capecitabine plus cisplatin for patients with advanced or recurrent gastric cancer

BACKGROUND

Based on the results of the SPIRITS trial, combination chemotherapy of S-1 plus cisplatin (SP) is now considered the standard treatment for patients with advanced gastric cancer (AGC) in Japan. On the other hand, several non-Japanese studies have shown the efficacy of capecitabine plus cisplatin (XP), which has been used as the reference arm in recent global studies of AGC.

METHODS

We retrospectively compared the efficacy and safety of SP and XP in first-line treatment for patients with AGC.

RESULTS

From August 2006 to November 2008, 26 AGC patients received XP in the context of 2 global trials (AVAGAST and ToGA), and 50 patients received SP during the same period. The objective response rate was 43.2 % in the SP group and 50 % in the XP group, with no significant difference (p = 0.62). There were also no significant differences in progression-free survival (median 5.8 vs. 5.2 months; p = 0.91) and overall survival (median 13.8 vs. 13.5 months; p = 0.97) between the SP and XP groups. The frequencies of hematological toxicities of grade 3 or more and non-hematological toxicities were not significantly different between the 2 groups. Although grade 1 or 2 hand-foot syndrome was more common in the XP group, no patients experienced grade 3 or more.

CONCLUSIONS

Although the retrospective nature of this study and the small number of patients is a major limitation, SP and XP were associated with similar efficacy and safety in patients with AGC.

HER-2 expression in immunohistochemistry has no prognostic significance in gastric cancer patients

The role of HER-2 expression as a prognostic factor in gastric cancer (GC) is still controversial. The aim of the study was to asses HER-2 status, its correlations with clinicopathological parameters, and prognostic impact in GC patients. Tumor samples were collected from 78 patients who had undergone curative surgery. In order to evaluate the intensity of immunohistochemical (IHC) reactions two scales were applied: the immunoreactive score according to Remmele modified by the authors and standardised Hercep test score modified for GC by Hofmann et al. The HER-2 overexpression was detected by IHC in 23 (29.5%) tumors in Hercep test (score 2+/3+) and in 24 (30.7%) in IRS scale (IRS 4–12). The overexpression of HER-2 was associated with poorly differentiated tumors, but this correlation was not significant (P = 0.064). No relationship was found between HER-2 expression and primary tumor size and degree of spread to regional lymph nodes. Both univariate and multivariate analyses revealed that TNM stage and patient's age were the crucial negative prognostic factors. No correlation was observed between patient survival and expression of HER-2 estimated using both scales. This research did not confirm HER-2 expression (evaluated with immunohistochemistry) value as a prognostic tool in GC.

Coexistence of gastric adenocarcinoma and choriocarcinoma: complete response to trastuzumab and chemotherapy

Gastric choriocarcinoma is a rare neoplasm and usually accompanies gastric adenocarcinoma. The prognosis is poor due to the aggressive course of the disease. A 57-year-old female patient with weight loss and abdominal pain was examined. The patient was operated following the examination, and pathological analysis revealed the presence of a gastric adenocarcinoma associated with choriocarcinoma. Immunohistochemical analysis showed a positive reaction with antibodies to beta-human chorionic gonadotropin and overexpression of the cErbB2 proto-oncogene. Staging revealed multiple metastases in the liver. A complete response was obtained with a combination of trastuzumab and chemotherapy. The diagnosis of gastric choriocarcinomas without pathological examination is difficult due to their rare occurrence. A complete response can be obtained with trastuzumab in the treatment of cases with overexpression of the cErbB2 protein.

HER2 testing in gastric cancer: a practical approach

Trastuzumab in combination with capecitabine or 5-fluorouracil and cisplatin is approved by the European Medicines Agency for the treatment of patients with human epidermal growth factor receptor 2 (HER2)-positive (immunohistochemistry 3+ or immunohistochemistry 2+/fluorescence in situ hybridization-positive or immunohistochemistry 2+/silver in situ hybridization-positive) metastatic adenocarcinoma of the stomach or gastro-esophageal junction. Approvals are underway in other countries, with recent approvals granted in the United States and Japan. Experience and data from trastuzumab use in breast cancer have highlighted the importance of quality HER2 testing and scoring to ensure accurate identification of patients eligible for treatment. HER2 testing in gastric cancer differs from testing in breast cancer due to inherent differences in tumor biology; gastric cancer more frequently shows HER2 heterogeneity (focal staining) and incomplete membrane staining. Consequently, gastric cancer-specific HER2 testing protocols have been developed and standardized and it is imperative that these recommendations be adhered to. Given the predictive value of HER2 protein levels with response in the trastuzumab for GAstric cancer study (ToGA), immunohistochemistry should be the initial testing methodology and fluorescence in situ hybridization or silver in situ hybridization should be used to retest immunohistochemistry 2+ samples. Wherever possible, bright-field methodologies should be used as these are considered to be superior to fluorescent methodologies at identifying heterogeneous staining. Specific training is required before embarking on HER2 testing in gastric cancer, irrespective of the experience of HER2 testing in breast cancer. This paper provides the most up-to-date practical guidance on HER2 testing and scoring in patients with gastric and gastro-esophageal junction cancer, as agreed by a panel of expert pathologists with extensive experience of HER2 testing particularly reflecting the European Medicines Agency-approved indication. It is anticipated that these recommendations should ensure accurate and consistent HER2 testing, which will allow appropriate selection of patients eligible for treatment with trastuzumab.

Selective PI3K inhibition by BKM120 and BEZ235 alone or in combination with chemotherapy in wild-type and mutated human gastrointestinal cancer cell lines

PURPOSE

New targeted agents like antibodies or small molecules against tyrosine and lipid kinases clearly expand the standard therapy options in oncology. However, tumour resistance is still a challenge, often induced by mutations in growth-related signalling cascades. Twenty and ten percentage of all patients with colorectal and gastric cancers, respectively, carry phosphatidyl-3-kinase (PI3K) mutations and do not respond to receptor-blocking therapies. Recently, selective kinase inhibitors have been generated, which block the PI3K signalling pathway in tumour cells. So far, their therapeutic role for the treatment of mutated versus wild-type human gastrointestinal cancers has not been clarified in detail.

METHODS

To define the inhibitory and pro-apoptotic effects of the two PI3K inhibitors BEZ235 and BKM120 in three human colon cancer (HT-29, HCT-116 and DLD-1) and three gastric cancer (NCI-n87, AGS and MKN-45), cell lines with different PIK3CA gene mutation status were used. Firstly, viability, apoptosis and caspase assays were performed during incubation with either the inhibitors alone or combined with different cytotoxic agents. Secondly, the molecular consequences for the cell cycle and signalling pathways were analysed by defining the protein levels by FACS and Western blot analysis.

RESULTS

Both the PI3K inhibitors BEZ235 and BKM120 induced a clear concentration-dependent reduction in cell viability and an increase in apoptotic cell death, with the mutated cells being more sensitive to treatment. However, single-agent BEZ235 caused a G1 arrest in tumour cells, whilst BKM120 induced a G2 shift in a half of the gastrointestinal cancer cell lines. There was a clear downregulation in the protein levels of the PI3K-AKT pathway at the concentrations of 100 nM for both agents and for BEZ235 the additional inhibition of the mTOR pathway. Furthermore, BEZ235 caused synergistic induction of apoptosis when combined with irinotecan in colon cancer cell lines. Human gastric cancer cells were less sensitive to both BEZ235 and BKM120.

CONCLUSIONS

BEZ235 and BKM120 induced pro-apoptotic effects in all cell lines and especially with an increased response in the PI3KCA mutated cells. Our data support the clinical development of these PI3K inhibitors for patients with wild-type or mutated colon cancers.

The risk for anemia with targeted therapies for solid tumors

BACKGROUND

Anemia is a common manifestation in patients with cancer. Little is known about the frequency of and risk for anemia with targeted therapies used to treat solid tumors.

METHODS

We performed a meta-analysis of randomized controlled trials of solid tumors by comparing targeted therapy (alone or in combination) with standard therapy alone to calculate the incidence and relative risk (RR) for anemia events associated with these agents. Overall, 24,310 patients were included in the analysis.

RESULTS

The addition of targeted therapies to standard treatment (chemotherapy or placebo/best supportive care) increased the risk for all grades of anemia by 7%. The RR for all grades (incidence, 44%) and grades 1-2 (incidence, 38.9%) of anemia was higher with biological therapies alone but not when combined with chemotherapy. The risk was significant for erlotinib, trastuzumab, and sunitinib. Bevacizumab was associated with a lower risk for anemia. Anti-epidermal growth factor receptor, anti-human epidermal growth factor receptor 2, anti-vascular endothelial growth factor receptors, and tyrosine kinase inhibitors predicted RRs of 1.24, 1.20, 0.82, and 1.33, respectively, and all of these values were significant.

CONCLUSION

Grade 1-2 anemia is frequently associated with biological agents. The risk is particularly associated with small-molecule tyrosine kinase inhibitors (gefitinib and erlotinib), breast cancer, and lung cancer. Erythropoiesis-stimulating agents are not labeled for use with targeted therapies (without chemotherapy) and the treatment is supportive only.

Clinical trials in gastric cancer and the future

Following the first successful gastric resection for gastric cancer by Theodor Billroth in 1881 surgery has made tremendous progress leading to improved surgical mortality and morbidity. However, while treatment of early gastric cancer is frequently curative, 5-year survival rates for advanced gastric cancer remain dismal despite the application of perioperative multimodal treatment concepts. In this article we will outline key clinical trials that have lead to an improvement in treatment of gastric cancer patients with specific emphasis on the last 20 years. We will then outline recent concepts and key clinical trials that are currently being conducted in the field. Finally we will outline open questions that remain to be elucidated in the future.

[Gastric cancer and adenocarcinoma of the esophagogastric junction: principles of neoadjuvant therapy]

According to the current European and German S3 guidelines, neoadjuvant chemotherapy is now an integral part of the treatment of locally advanced gastric cancer and adenocarcinoma of the esophagogastric junction. Neoadjuvant therapy seeks to achieve downsizing of the primary tumor, lowering of the T and N categories and eradication of micrometastases. As the indications for neoadjuvant treatment are based on pretherapeutic information alone, a sophisticated clinical staging plays a central role. Despite all progress made in the field of diagnostic work-up, clinical staging often fails. Despite this fact, controlled randomized trials showed that neoadjuvant chemotherapy enhances the rate of curative (R0) resections and reduces the likelihood of systemic relapse. Overall, survival can be improved by neoadjuvant chemotherapy. The current research is focused on the molecular prediction of response and early response monitoring with functional imaging. New targeted drugs are being integrated into the peri-operative treatment.

HER2 expression in gastric and gastroesophageal junction adenocarcinoma in a US population: clinicopathologic analysis with proposed approach to HER2 assessment

Recent evidence suggests that trastuzumab, a monoclonal antibody which targets HER2, in combination with chemotherapy is a therapeutic option in patients with HER2-positive gastric or gastroesophageal junction cancer. Widely accepted guidelines for HER2 testing in gastric and gastroesophageal junction cancer have not been established. The purpose of this study was to analyze the incidence and patterns of HER2 expression in gastric and gastroesophageal junction cancer using a tissue microarray approach, which closely simulates small biopsies routinely tested for HER2. One hundred sixty-nine patients, including 99 primary gastric adenocarcinomas and 70 primary gastroesophageal junction carcinomas were analyzed for HER2 overexpression by immunohistochemistry and HER2 gene amplification by fluorescence in situ hybridization using scoring schemes proposed by both American Society of Clinical Oncology/College of American Pathologists (ASCO/CAP) and the results of the recently published Trastuzumab for Gastric Cancer (ToGA) trial. In our analysis, 19 adenocarcinomas were HER2 positive, defined as either a HER2/CEP17 ratio >2.2 and/or a 3+ HER2 immunohistochemistry score with either the ASCO/CAP or ToGA scoring schemes. Of the 19 HER2-positive adenocarcinomas, 8 (42%) exhibited a characteristic strongly intense basolateral membranous staining pattern which would be interpreted as negative (1+) using the accepted ASCO/CAP scoring scheme for HER2 assessment in breast carcinoma, but were correctly labeled as 3+ positive using the proposed ToGA scoring scheme. Of the 19 HER2-positive adenocarcinomas, 8 (42%) demonstrated heterogeneous HER2 protein expression by immunohistochemistry. Twelve of 99 (12%) gastric carcinomas were positive for HER2. Of these, HER2 was more often identified in intestinal-type adenocarcinomas (10 of 52, 19%) compared with diffuse (2 of 34, 6%) adenocarcinoma. Seven of 70 (10%) gastroesophageal junction carcinomas were positive for HER2 of which all were intestinal type (7 of 58, 12%). HER2 status or primary tumor site did not correlate with patient survival. Gastric and gastroesophageal junction adenocarcinomas typically display a characteristic basolateral membranous pattern of HER2 expression which is often heterogeneous rendering routine evaluation of HER2 status on small tissue samples challenging.

HER2 amplification in gastroesophageal adenocarcinoma: correlation of two antibodies using gastric cancer scoring criteria, H score, and digital image analysis with fluorescence in situ hybridization

We assessed 103 resected gastroesophageal adenocarcinomas for HER2 amplification by fluorescence in situ hybridization (FISH) and 2 commercial immunohistochemical assays. Of 103, 30 (29%) were FISH-amplified. Both immunohistochemical assays had greater than 95% concordance with FISH. However, as a screening test for FISH amplification, the Ventana Medical Systems (Tucson, AZ) 4B5 antibody demonstrated superior sensitivity (87%) compared with the DAKO (Carpinteria, CA) A0485 (70%). Of the cases, 28 were immunohistochemically 3+ or immunohistochemically 2+/FISH-amplified with the 4B5 assay compared with only 22 cases with the A0485 assay, representing a large potential difference in patient eligibility for anti-HER2 therapy. Cases with low-level FISH amplification (HER2/CEP17, 2.2-4.0) express lower levels of HER2 protein compared with cases with high-level amplification (HER2/CEP17, ≥4.0), raising the possibility of a differential response to anti-HER2 therapy. The H score and digital image analysis may have a limited role in improving HER2 test performance.

Reporting patient characteristics and stratification factors in randomized trials of systemic chemotherapy for advanced gastric cancer

BACKGROUND

There is no consensus on which patient characteristics are the most suitable to report or to be used as stratification factors in clinical trials for advanced gastric cancer (AGC), to our knowledge.

METHODS

We conducted a comprehensive review of published randomized trials for AGC to examine the patient characteristics that were reported.

RESULTS

Among the 67 analyzed trials, age, gender, performance status, proportion of patients with measurable disease, and previous gastrectomy were frequently reported (>69%). Histology, number of disease sites, and adjuvant treatment were reported in less than 50% of trials. Although the reporting of second-line chemotherapy has increased in recent trials, it remains at less than 50%. Notably, recent trials have tended to include patients with better performance status and less locally advanced disease, with Asian trials more frequently including patients with more diffuse histology and less locally advanced disease or liver metastasis than non-Asian trials. Stratification was conducted in approximately 60% of the trials, using quite variable stratifying factors.

CONCLUSION

Inconsistency exists in the reporting of patient characteristics, the characteristics themselves, and the use of stratification factors in clinical trials for AGC. A consensus set of important patient characteristics and strata may be necessary to conduct and interpret quality randomized studies.

Management of advanced gastric cancer

The management of advanced gastric cancer has only evolved a little over the last 15 years: platinum and fluoropyrimidine chemotherapy remains the backbone of therapy with ongoing debate as to the benefit of triplet therapy with either an anthracycline or taxane. Recently published trials of biological agents, in particular those targeting the Her2 receptor, have provided some signs of improvement. This article summarizes the relevant literature, discusses the role of these agents, as well as geographical variations in use, and provides recommendations regarding both 'standard chemotherapy' and the role of biological agents in advanced gastric cancer. Given the relative lack of progress for gastric cancer over the last 15 years, the focus for the next 5 years should be on an improved understanding of the molecular basis of gastric cancer, thus allowing rational integration of new molecular agents.

Prognostic value of RKIP and p-ERK in gastric cancer

BACKGROUND

The mitogen-activated protein kinase (MAPK) signaling pathway participates in several steps of tumour development and is considered a prominent therapeutic target for the design of chemotherapeutic agents. We evaluated the expressions of extracellular signal-regulated kinase (ERK), mitogen-activated protein kinase (MEK), an upstream regulator of ERK, and Raf kinase inhibitor protein (RKIP), and investigated correlations of these expressions with clinicopathological features and outcomes in gastric cancer.

METHODS

Tumour samples were obtained from 105 patients with gastric adenocarcinomas who underwent radical gastrectomy. The expressions of phosphorylated ERK (p-ERK), phosphorylated MEK (p-MEK), and RKIP were analysed by immunohistochemical staining.

RESULTS

Expression of RKIP, p-MEK, and p-ERK was found in 69 (66%), 54 (51%), and 64 (61%) of all tumours, respectively. RKIP expression negatively correlated with the depth of invasion (p < 0.001), lymph node involvement (p = 0.028), and Union for International Cancer Control (UICC) stage (p = 0.007). RKIP expression was associated with significantly longer relapse-free survival (RFS) (p = 0.0033), whereas p-MEK was not (p = 0.79). Patients with p-ERK expression had slightly, but not significantly shorter RFS than those without such expression (p = 0.054). Patients with positive p-ERK and negative RKIP expression had significantly shorter RFS than the other patients (p < 0.001). The combination of RKIP and p-ERK expression was an independent prognostic factor (hazard ratio, 2.4; 95% confidence interval, 1.3 - 4.6; p = 0.008).

CONCLUSIONS

Our results demonstrated that loss of RKIP was associated with tumour progression and poor survival. Negative RKIP expression combined with positive p-ERK expression was an independent predictor of poor outcomes in patients with gastric cancer.

Update of adjuvant chemotherapy for resected gastric cancer

Gastric cancer is the second cause of cancer that is related to death and the fourth most common cancer, worldwide. Complete resection of cancer is the only curative treatment for gastric cancer. However, even if complete resection is possible, recurrence is frequently observed in Gastric patients. Therefore, adjuvant treatment modality for resectable gastric cancer is needed to increase the survival of patients. This study wants to describe the role of adjuvant chemotherapy for resectable gastric cancer, with updated data of recent studies. Several meta-analysis studies demonstrated a benefit of adjuvant chemotherapy for resectable gastric cancer. Due to the heterogeneity of the population and regimens, there is no consensus regarding the adjuvant chemotherapy. Recently published, well designed phase III studies demonstrated the statistically significance of adjuvant chemotherapy for the resectable gastric cancer, with the extended lymph node dissection. Further phase III trials, to determine the best regimen and schedule of adjuvant chemotherapy, was suggested to use the fluoropyrimidine based regimen as control group.

Update of adjuvant chemotherapy for resected gastric cancer

Gastric cancer is the second cause of cancer that is related to death and the fourth most common cancer, worldwide. Complete resection of cancer is the only curative treatment for gastric cancer. However, even if complete resection is possible, recurrence is frequently observed in Gastric patients. Therefore, adjuvant treatment modality for resectable gastric cancer is needed to increase the survival of patients. This study wants to describe the role of adjuvant chemotherapy for resectable gastric cancer, with updated data of recent studies. Several meta-analysis studies demonstrated a benefit of adjuvant chemotherapy for resectable gastric cancer. Due to the heterogeneity of the population and regimens, there is no consensus regarding the adjuvant chemotherapy. Recently published, well designed phase III studies demonstrated the statistically significance of adjuvant chemotherapy for the resectable gastric cancer, with the extended lymph node dissection. Further phase III trials, to determine the best regimen and schedule of adjuvant chemotherapy, was suggested to use the fluoropyrimidine based regimen as control group.

Randomised phase II trial of docetaxel and sunitinib in patients with metastatic gastric cancer who were previously treated with fluoropyrimidine and platinum

BACKGROUND

Docetaxel is widely used as a chemotherapeutic agent for gastric cancer treatment. A combined regimen with sunitinib demonstrated a synergistic antitumour effect in a preclinical model. The aim of this study was to evaluate the efficacy and safety of this combination in patients with unresectable or metastatic advanced gastric cancer following failure of treatment with a fluoropyrimidine and platinum combination.

METHODS

This open-label, phase II, randomised trial enrolled patients with unresectable or metastatic gastric cancer. Patients were assigned to either a docetaxel monotherapy arm (D only arm: 60 mg m(-2), every 3 weeks) or a combination arm (DS arm: docetaxel+sunitinib 37.5 mg every day). The primary end point of the study was time to progression and the secondary end points were overall response rate, disease control rate, overall survival, and toxicity profile. A pharmacokinetic study was also performed.

RESULTS

A total of 107 patients were entered into the study. The TTP was not significantly prolonged in the DS arm when compared with the D only arm (DS vs D only arm: 3.9 months (95% confidence interval (CI) 2.9-4.9) vs 2.6 months (95% CI 1.8-3.5) (P=0.206). The hazard ratio for TTP was 0.77 (95% CI 0.52-1.16). However, the objective response rate was significantly higher in the DS arm (41.1% vs 14.3%, P=0.002). Patients in the DS arm experienced stomatitis, diarrhoea, and hand-foot syndrome more frequently.

CONCLUSION

The addition of sunitinib to docetaxel did not significantly prolong TTP, although it significantly increased response.

Randomised phase II trial of docetaxel and sunitinib in patients with metastatic gastric cancer who were previously treated with fluoropyrimidine and platinum

BACKGROUND

Docetaxel is widely used as a chemotherapeutic agent for gastric cancer treatment. A combined regimen with sunitinib demonstrated a synergistic antitumour effect in a preclinical model. The aim of this study was to evaluate the efficacy and safety of this combination in patients with unresectable or metastatic advanced gastric cancer following failure of treatment with a fluoropyrimidine and platinum combination.

METHODS

This open-label, phase II, randomised trial enrolled patients with unresectable or metastatic gastric cancer. Patients were assigned to either a docetaxel monotherapy arm (D only arm: 60 mg m(-2), every 3 weeks) or a combination arm (DS arm: docetaxel+sunitinib 37.5 mg every day). The primary end point of the study was time to progression and the secondary end points were overall response rate, disease control rate, overall survival, and toxicity profile. A pharmacokinetic study was also performed.

RESULTS

A total of 107 patients were entered into the study. The TTP was not significantly prolonged in the DS arm when compared with the D only arm (DS vs D only arm: 3.9 months (95% confidence interval (CI) 2.9-4.9) vs 2.6 months (95% CI 1.8-3.5) (P=0.206). The hazard ratio for TTP was 0.77 (95% CI 0.52-1.16). However, the objective response rate was significantly higher in the DS arm (41.1% vs 14.3%, P=0.002). Patients in the DS arm experienced stomatitis, diarrhoea, and hand-foot syndrome more frequently.

CONCLUSION

The addition of sunitinib to docetaxel did not significantly prolong TTP, although it significantly increased response.

Leptin and HER-2 are associated with gastric cancer progression and prognosis of patients

We conducted this study to evaluate the expression of leptin and its receptor, OB-Rb in gastric cancer and their relationship to clinicopathological features, VEGF and HER-2 expression, as well as the prognostic value. One hundred and ten gastric cancer specimens were detected for leptin, OB-Rb, VEGF and HER-2 by immunohistochemistry (IHC), and 96 specimens of normal gastric mucosa served as the control. The expression level of leptin, OB-Rb and HER-2 in gastric tissues were significantly higher than normal tissues (49.1% vs. 34.0%, 60.9% vs. 46.0%, 19.1% vs. 8.0%, P<0.05). There was a correlation between the expression of leptin and HER-2, both of which were significantly associated with invasion depth, lymph node metastasis, AJCC stage and VEGF expression. However, there was no correlation between OB-Rb expression and all clinicopathological features. Cox regression analyses showed that age, tumor size, histological grade, serosa invasion, AJCC stage, chemotherapy, leptin and HER-2 overexpression were prognostic factors. The survival of patients with leptin positive expression was significantly poorer than those with negative expression (OS: 20.0 months vs. 32.5 months, FPS: 12.0 months vs. 18.0 months, P<0.01). Leptin, rather than OB-Rb, played an important role in the progression and angiogenesis of gastric cancer, and was a prognostic factor for poor outcome.

Current status of targeted therapies in advanced gastric cancer

INTRODUCTION

In metastatic gastric cancer, chemotherapy is the standard treatment because it prolongs survival when compared to best supportive care alone. However, even after the use of more effective regimens, the overall survival remains disappointing, justifying the need for new treatment options.

AREAS COVERED

Areas covered in this review include the most common molecular pathways, which have provided novel targets in gastric cancer therapy. These therapeutic strategies include EGFR inhibitors, anti-angiogenic agents, cell cycle inhibitors and apoptosis promoters.

EXPERT OPINION

Several mAbs and kinase inhibitors, especially those targeting EGFR and VEGF/VEGFR, have already demonstrated promising activity in gastric cancer. The Phase III ToGA trial reported an increase in overall survival for patients with human EGF receptor (HER)2-positive gastric cancer treated with chemotherapy and trastuzumab compared to chemotherapy alone. This means that accurate HER2 testing in gastric cancer is necessary. Final data of ongoing trials with novel agents will be critical to further progress with this cancer.

The genetic basis for cancer treatment decisions

Personalized cancer medicine is based on increased knowledge of the cancer mutation repertoire and availability of agents that target altered genes or pathways. Given advances in cancer genetics, technology, and therapeutics development, the timing is right to develop a clinical trial and research framework to move future clinical decisions from heuristic to evidence-based decisions. Although the challenges of integrating genomic testing into cancer treatment decision making are wide-ranging and complex, there is a scientific and ethical imperative to realize the benefits of personalized cancer medicine, given the overwhelming burden of cancer and the unprecedented opportunities for advancements in outcomes for patients.

Omics Screening for Pharmaceutical Efficacy and Safety in Clinical Practice

As molecular techniques have improved, investigators have attempted to improve pharmaceutical efficacy and safety by making trait associations with genomic, epigenomic, transcriptomic, proteomic, and metabolomic polymorphisms. The 'omics era has seen screening assays for pharmaceutical efficacy and safety translated into clinical practice. This manuscript will discuss each 'omic field and the screening assays available to the clinician. While success has been demonstrated in each 'omic field, many challenges remain. Assays need wider availability, predictive values remain low, and costs remain high. In order for clinicians to realize improved efficacy and safety due 'omic screens, development of improved techniques, combining of 'omic assays, and increased clinical utilization is necessary. This is an exciting time for investigators and clinicians that desire improved pharmaceutical therapy.

Trastuzumab for treatment of refractory/relapsed HER2-positive adult B-ALL: results of a phase 2 GRAALL study

The aim of this phase 2 study was to evaluate the efficacy and safety of trastuzumab, a humanized monoclonal antibody targeted against the human epidermal growth factor receptor 2 (HER2), for adult patients with relapsed/refractory HER2-positive B-ALL. Fifteen patients, with a median age of 62 years, received trastuzumab according to the schedule approved for breast cancer patients (ie, 4 mg/kg intravenous loading dose followed by 2 mg/kg weekly). The overall response rate was 13% with 2 patients achieving partial response and partial remission cytolytic response, respectively. Two other patients were documented with blast clearance. Only 1 reversible grade 3 cardiac toxic event occurred. This phase 2 study showed that trastuzumab monotherapy can allow for some responses in a very high-risk refractory/relapsed HER2-positive adult B-ALL population. Combination of trastuzumab with chemotherapy or other therapeutic monoclonal antibodies should be tested in the future. This trial was registered at www.clinicaltrials.gov/ct as NCT00724360.

HER2 as a Prognostic Marker in Gastric Cancer - A Systematic Analysis of Data from the Literature

Through the recent conduct of the ToGA trial, HER2 has shown to be predictive for the treatment with trastuzumab in advanced gastric and gastro-oesophageal cancer. When it comes to the prognostic properties the situation is different. Despite the fact that it is more than 20 years ago since the first studies demonstrating an association between a positive HER2 status and poor prognosis were published the issue is still controversial. In this current systematic review a large number of studies on HER2 and gastric cancer have been reviewed. The studies included in this review should fulfill the following two criteria. First criterion: The number of patients in each study should be ≥ 100, and the HER2 status should have been determined either by immunohistochemistry (IHC) or in situ hybridization (ISH). Second criterion: The selected articles should include an analysis of the association between the HER2 status and survival or relevant clinicopathological characteristics. Forty-two publications with a total of 12,749 patients fulfilled the two criteria and were reviewed in detail. The majority of the publications (71%) showed that a HER2-postive status measured either by IHC or ISH was associated with poor survival and/or clinicopathological characteristics, such as serosal invasion, lymph node metastases, disease stage, or distant metastases. Based on the current analysis a clear trend towards a potential role for HER2 as a negative prognostics factor in gastric cancer was shown, suggesting that HER2 overexpression and/or amplification is a molecular abnormality that might be linked to the development of gastric cancer.

Human epidermal growth factor receptor 2 testing in gastric carcinoma: issues related to heterogeneity in biopsies and resections

AIMS

To assess human epidermal growth factor receptor 2 (HER2) status and heterogeneity using immunohistochemistry (IHC) and silver in-situ hybridization (SISH) in gastric carcinoma and dysplasia, and to correlate HER2 status between biopsy and resection specimens of gastric carcinoma.

METHODS AND RESULTS

Immunohistochemistry for HER2 was performed in 178 cases of gastric carcinoma, and SISH in cases showing at least 1+ reaction. HER2 positivity [European Medicines Agency (EMA) guidelines] was identified in 20.2% of carcinomas and 12.9% of high-grade dysplasia, and HER2 heterogeneity noted in 50% and 33% of these cases, respectively. IHC negative/positive reactivity and SISH results were concordant in 96.2%. SISH amplification was seen in 35.3% of IHC 2+ and in a case with previously unrecognized staining pattern. Concordance of IHC HER2 status on biopsies and gastrectomies was seen in 74.1%. False negative IHC results on either the biopsy or gastrectomy were seen in 19.4% of HER2 amplified cases.

CONCLUSIONS

Human epidermal growth factor receptor 2 status in gastric carcinoma is comparable to previous studies with good concordance between IHC and SISH; all IHC 2+ and unusual patterns should be assessed with ISH studies; heterogeneity of tumour HER2 overexpression/amplification is common with possible implications for HER2 testing; and HER2 overexpression appears sufficiently specific to be considered a potential diagnostic biomarker of dysplasia.

Targeted therapies in the treatment of gastric cancer

Gastric cancer (GC) constitutes a major cause of cancer deaths worldwide. Recent improvements in both surgical techniques and adjuvant and neoadjuvant radiotherapy and chemotherapy approaches have increased the survival of patients with loco-regional disease. However most patients with GC have advanced disease either at diagnosis or at follow up. Despite recent advances in the treatment of advanced disease, these patients still have poor outcomes. An emerging understanding of the molecular pathways that characterize cell growth, cell cycle, apoptosis, angiogenesis and invasion has provided novel targets in cancer therapy. In this review we describe the current status of targeted therapies in the treatment of GC. These therapeutic strategies include epidermal growth factor receptor inhibitors, antiangiogenic agents, cell cycle inhibitors, apoptosis, promoters and matrix metalloproteinases inhibitors.

HER2 testing in gastric and gastroesophageal junction cancers: a new therapeutic target and diagnostic challenge

Adenocarcinomas of the stomach and gastroesophageal junction represent a major cause of cancer morbidity and mortality world wide. Complete surgical resection is the mainstay of treatment for nonmetastatic disease; however, many patients are not diagnosed until their disease is either locally advanced or metastatic and therefore unresectable. Clearly, there is an unmet clinical need for new therapeutic strategies, treatment options, and novel therapeutic targets. In a recent trial (Trastuzumab for GAstric cancer), patients assigned to the trastuzumab treatment protocol showed an improved overall survival over those not receiving treatment. Trastuzumab has recently been approved for treatment of advanced gastric and gastroesophageal junction cancers. Pathologists and diagnostic laboratories must be prepared for this new category of specimens requiring human epidermal growth factor receptor 2 testing, and have an awareness of the interpretive differences between breast and gastric cancers.

Chemotherapy for gastric cancer patients - time for personalization in medicine?

Gastric cancer is one of the most frequent neoplasms. Although the incidence of gastric cancer worldwide has declined, there is still high mortality. Treatment of inoperable disease is under evaluation in clinical trials. In palliative treatment chemotherapy containing cisplatin and 5-fluorouracil is the most widely used. In the past years progress in tumour biology has advanced greatly and has led to development of new molecules aimed at targets important for cancer expansion. There are several randomized trials under targeted therapies for gastric cancer patients. One of them led to approval of trastuzumab. In the current paper the authors illustrate new possibilities in systemic treatment with particular attention to targeted therapy and personalization in medicine.

Multicentre phase II trial of trastuzumab and capecitabine in patients with HER2 overexpressing metastatic pancreatic cancer

Background:

New therapeutic options for metastatic pancreatic cancer are urgently needed. In pancreatic cancer, overexpression of the epidermal growth factor receptor 2 (HER2) has been reported in up to 45%. This multicentre phase II study investigated the efficacy and toxicity of the HER2 antibody trastuzumab combined with capecitabine in the patients with pancreatic cancer and HER2 overexpression.

Methods:

Primary endpoint was progression-free survival (PFS) after 12 weeks. A total of 212 patients were screened for HER2 expression.

Results:

Immunohistochemical (IHC) HER2 expression was: 83 (40%) grade 0, 71 (34%) grade 1, 31 (15%) grade 2, 22 (11%) grade 3. A total of 17 patients with IHC +3 HER2 expression or gene amplification could be assessed for the treatment response. Grade 3/4 treatment toxicities were: each 7% leucopenia, diarrhoea, nausea and hand-foot syndrome. Progression-free survival after 12 weeks was 23.5%, median overall survival (OS) 6.9 months.

Conclusion:

This study demonstrates +3 HER2 expression or gene amplification in 11% of patients. Contrary to breast and gastric cancer, only 7 out of 11 (64%) patients with IHC +3 HER2 expression showed gene amplification. Although the therapy was well tolerated, PFS and OS did not perform favourably compared with standard chemotherapy. Together, we do not recommend further evaluation of anti-HER2 treatment in patients with metastatic pancreatic cancer.

Phase I and II clinical trials for gastric cancer

Gastric cancer remains a global public health problem with considerable heterogeneity in pathogenesis and clinical presentation across geographic regions. Improved understanding of the molecular biology of this disease has opened avenues for targeted intervention. An individualized treatment approach is required for optimal management of this cancer. Overcoming resistance to therapy requires combining targeted agents with the traditional options of chemotherapy/radiation therapy, and also targeting more than 1 pathway of carcinogenesis at a time. Encouraging molecular hypothesis and biomarker-driven trials will lead to improved patient outcomes and may eventually enable the therapeutic nihilism associated with gastric cancer to be overcome.

Tumor-associated antigens for specific immunotherapy of prostate cancer

Prostate cancer (PCa) is the most common noncutaneous cancer diagnosis and the second leading cause of cancer-related deaths among men in the United States. Effective treatment modalities for advanced metastatic PCa are limited. Immunotherapeutic strategies based on T cells and antibodies represent interesting approaches to prevent progression from localized to advanced PCa and to improve survival outcomes for patients with advanced disease. CD8⁺ cytotoxic T lymphocytes (CTLs) efficiently recognize and destroy tumor cells. CD4⁺ T cells augment the antigen-presenting capacity of dendritic cells and promote the expansion of tumor-reactive CTLs. Antibodies mediate their antitumor effects via antibody-dependent cellular cytotoxicity, activation of the complement system, improving the uptake of coated tumor cells by phagocytes, and the functional interference of biological pathways essential for tumor growth. Consequently, several tumor-associated antigens (TAAs) have been identified that represent promising targets for T cell- or antibody-based immunotherapy. These TAAs comprise proteins preferentially expressed in normal and malignant prostate tissues and molecules which are not predominantly restricted to the prostate, but are overexpressed in various tumor entities including PCa. Clinical trials provide evidence that specific immunotherapeutic strategies using such TAAs represent safe and feasible concepts for the induction of immunological and clinical responses in PCa patients. However, further improvement of the current approaches is required which may be achieved by combining T cell- and/or antibody-based strategies with radio-, hormone-, chemo- or antiangiogenic therapy.

Targeted therapy in the management of advanced gastric cancer: are we making progress in the era of personalized medicine?

BACKGROUND

Gastric cancer is one of the leading causes of cancer death. With greater understanding of the molecular basis of carcinogenesis, targeted agents have led to a modest improvement in the outcome of advanced gastric cancer (AGC) patients.

METHODS AND RESULTS

We conducted an overview of the published evidence regarding the use of targeted therapy in AGC patients. Thus far, the human epidermal growth factor receptor (HER) pathway, angiogenic pathway, and phosphatidylinositol-3-kinase (PI3K)-Akt-mammalian target of rapamycin pathway have emerged as potential avenues for targeted therapy in AGC patients. The promising efficacy results of the Trastuzumab for Gastric Cancer trial led to the approved use of trastuzumab-based therapy as first-line treatment for patients with HER-2+ AGC. On the other hand, the Avastin® in Gastric Cancer trial evaluating bevacizumab in combination with chemotherapy did not meet its primary endpoint of a longer overall survival duration despite a significantly higher response rate and longer progression-free survival time in patients in the bevacizumab arm. Phase III data are awaited for other targeted agents, including cetuximab, panitumumab, lapatinib, and everolimus.

CONCLUSION

Recent progress in targeted therapy development for AGC has been modest. Further improvement in the outcome of AGC patients will depend on the identification of biomarkers in different patient populations to facilitate the understanding of gastric carcinogenesis, combining different targeted agents with chemotherapy, and unraveling new molecular targets for therapeutic intervention.

Recent progress in carcinogenesis, progression and management of upper GI cancer: the 21st Hiroshima Cancer Seminar--the 5th Three Universities' Consortium International Symposium, 6 November 2011, International Conference Center Hiroshima

The 21st Hiroshima Cancer Seminar focused on recent progress of carcinogenesis, progression and management of upper gastrointestinal cancers. β-Catenin and p120 mediate peroxisome proliferator-activated receptor δ-dependent proliferation induced by Helicobacter pylori in gastric epithelia. Helicobacter pylori CagA plays an important role in stomach carcinogenesis via altered signal transduction and cell polarity by interactions with several host proteins. Inflammation caused by H. pylori infection is responsible for inducing aberrant DNA methylation. The gastric gland mucin-specific αGlcNAc plays dual roles in preventing gastric cancer, inhibition of H. pylori infection and suppression of tumor-promoting inflammation. Information obtained from transcriptome dissection greatly contributes to understanding the molecular character of each mucin phenotype of gastric cancer. The standardized biomarkers will serve as good predictive and prognostic markers for gastric cancer. A microRNA expression profile may be useful for the diagnosis of gastric cancer. Bone marrow-derived mesenchymal stem cells may provide an advantageous microenvironment for re-acquisition of stemness of gastric cancer cells. Recent progress in molecular biology research has enabled the clinical development of molecular targeting agents for gastric cancer, such as trastuzumab. The target molecule-based inhibition of the stromal reaction in the microenvironment may hold promise as an effective anti-tumor therapy. Since robotic surgery is feasible and safe, and provides adequate and precise lymph node dissection, it may be one of the good options for gastric cancer in the near future.

Cancer biomarkers

Biomarkers have many potential applications in oncology, including risk assessment, screening, differential diagnosis, determination of prognosis, prediction of response to treatment, and monitoring of progression of disease. Because of the critical role that biomarkers play at all stages of disease, it is important that they undergo rigorous evaluation, including analytical validation, clinical validation, and assessment of clinical utility, prior to incorporation into routine clinical care. In this review we address key steps in the development of biomarkers, including ways to avoid introducing bias and guidelines to follow when reporting results of biomarker studies.

Fibroblast growth factor receptor-3 in urothelial tumorigenesis

Fibroblast growth factor receptor-3 (FGFR3) is a receptor tyrosine kinase implicated in the tumorigenesis of multiple malignancies, including bladder and other urothelial cancers, multiple myeloma, and cervical cancer. In urothelial carcinoma (UC), constitutive receptor activation occurs most commonly through substitution of a wild-type residue with cysteine in the extracellular domain of FGFR3, thereby resulting in dimerization (through disulfide bridge formation) and subsequent stimulation of tyrosine kinase activity. Activating mutations of FGFR3 have been observed in up to 70% of non-muscle-invasive bladder tumors, while overexpression of a wild-type receptor, found in approximately 40% of tumors, has been correlated with more invasive disease. The identification of FGFR3 mutations in UC has sparked substantial interest in the therapeutic exploitation of these aberrations, and in vitro studies have provided evidence that such alterations may represent driver oncogenic lesions. In this review, we discuss the biologic and prognostic impact of FGFR3 mutations in UC as well as FGFR3 as a potential target for novel therapeutics.

Adjuvant capecitabine and oxaliplatin for gastric cancer after D2 gastrectomy (CLASSIC): a phase 3 open-label, randomised controlled trial

BACKGROUND

D2 gastrectomy is recommended in US and European guidelines, and is preferred in east Asia, for patients with resectable gastric cancer. Adjuvant chemotherapy improves patient outcomes after surgery, but the benefits after a D2 resection have not been extensively investigated in large-scale trials. We investigated the effect on disease-free survival of adjuvant chemotherapy with capecitabine plus oxaliplatin after D2 gastrectomy compared with D2 gastrectomy only in patients with stage II-IIIB gastric cancer.

METHODS

The capecitabine and oxaliplatin adjuvant study in stomach cancer (CLASSIC) study was an open-label, parallel-group, phase 3, randomised controlled trial undertaken in 37 centres in South Korea, China, and Taiwan. Patients with stage II-IIIB gastric cancer who had had curative D2 gastrectomy were randomly assigned to receive adjuvant chemotherapy of eight 3-week cycles of oral capecitabine (1000 mg/m(2) twice daily on days 1 to 14 of each cycle) plus intravenous oxaliplatin (130 mg/m(2) on day 1 of each cycle) for 6 months or surgery only. Block randomisation was done by a central interactive computerised system, stratified by country and disease stage. Patients, and investigators giving interventions, assessing outcomes, and analysing data were not masked. The primary endpoint was 3 year disease-free survival, analysed by intention to treat. This study reports a prespecified interim efficacy analysis, after which the trial was stopped after a recommendation by the data monitoring committee. The trial is registered at ClinicalTrials.gov (NCT00411229).

FINDINGS

1035 patients were randomised (520 to receive chemotherapy and surgery, 515 surgery only). Median follow-up was 34·2 months (25·4-41·7) in the chemotherapy and surgery group and 34·3 months (25·6-41·9) in the surgery only group. 3 year disease-free survival was 74% (95% CI 69-79) in the chemotherapy and surgery group and 59% (53-64) in the surgery only group (hazard ratio 0·56, 95% CI 0·44-0·72; p<0·0001). Grade 3 or 4 adverse events were reported in 279 of 496 patients (56%) in the chemotherapy and surgery group and in 30 of 478 patients (6%) in the surgery only group. The most common adverse events in the intervention group were nausea (n=326), neutropenia (n=300), and decreased appetite (n=294).

INTERPRETATION

Adjuvant capecitabine plus oxaliplatin treatment after curative D2 gastrectomy should be considered as a treatment option for patients with operable gastric cancer.

FUNDING

F Hoffmann-La Roche and Sanofi-Aventis.

Biomarkers for antitumor activity of bevacizumab in gastric cancer models

Background

Bevacizumab is a humanized monoclonal antibody to human vascular endothelial cell growth factor (VEGF) and has been used for many types of cancers such as colorectal cancer, non-small cell lung cancer, breast cancer, and glioblastoma. Bevacizumab might be effective against gastric cancer, because VEGF has been reported to be involved in the development of gastric cancer as well as other cancers. On the other hand, there are no established biomarkers to predict the bevacizumab efficacy in spite of clinical needs. Therefore, we tried to identify the predictive markers for efficacy of bevacizumab in gastric cancer patients by using bevacizumab-sensitive and insensitive tumor models.

Methods

Nine human gastric and two colorectal cancer mouse xenografts were examined for their sensitivity to bevacizumab. We examined expression levels of angiogenic factors by ELISA, bioactivity of VEGF by phosphorylation of VEGFR2 in HUVEC after addition of tumor homogenate, tumor microvessel density by CD31-immunostaining, and polymorphisms of the VEGF gene by HybriProbe™ assay.

Results

Of the 9 human gastric cancer xenograft models used, GXF97, MKN-45, MKN-28, 4-1ST, SC-08-JCK, and SC-09-JCK were bevacizumab-sensitive, whereas SCH, SC-10-JCK, and NCI-N87 were insensitive. The sensitivity of the gastric cancer model to bevacizumab was not related to histological type or HER2 status. All tumors with high levels of VEGF were bevacizumab-sensitive except for one, SC-10-JCK, which had high levels of VEGF. The reason for the refractoriness was non-bioactivity on the phosphorylation of VEGFR2 and micro-vessel formation of VEGF, but was not explained by the VEGF allele or VEGF165b. We also examined the expression levels of other angiogenic factors in the 11 gastrointestinal tumor tissues. In the refractory models including SC-10-JCK, tumor levels of another angiogenic factor, bFGF, were relatively high. The VEGF/bFGF ratio correlated more closely with sensitivity to bevacizumab than with the VEGF level.

Conclusions

VEGF levels and VEGF/bFGF ratios in tumors were related to bevacizumab sensitivity of the xenografts tested. Further clinical investigation into useful predictive markers for bevacizumab sensitivity is warranted.