Lauren classification combined with HER2 status is a better prognostic factor in Chinese gastric cancer patients

Clinical utility of HER2 assessed by immunohistochemistry in patients undergoing curative resection for gastric cancer

Purpose

We sought to determine whether human epidermal growth factor receptor 2 (HER2) and vascular endothelial growth factor (VEGF) expression were independent prognostic factors for gastric cancer (GC).

Patients and methods

A total of 678 consecutive patients with GC undergoing curative surgery between October 2010 and December 2012 had resected tissue examined for HER2 and VEGF expression using immunohistochemistry. Immunohistochemical expression of HER2 was analyzed using the DAKO-HercepTest™ and scored according to published reports. VEGF expression was calculated by multiplying the score for the percentage of positive cells by the intensity score. We defined positive expression as a score of 1+, 2+, or 3+, and a score of 0 was defined as negative expression. We compared these results to clinicopathological characteristics, including overall survival (OS).

Results

Multivariate analysis revealed that HER2 expression was independently associated with shorter OS (hazard ratio [HR], 1.55; 95% confidence interval [CI], 1.10–2.18; P=0.01) and with higher tumor–nodes–metastasis stage (HR, 3.88; 95% CI, 2.67–5.64; P<0.001) in patients with GC. VEGF expression was not associated with OS (HR, 1.25; 95% CI, 0.86–1.82; P=0.24). HER2 expression was still identified as an independent prognostic factor in Stage II–III patients treated with surgery and adjuvant chemotherapy (P=0.004) but not in patients who received surgery alone (P=0.61). Among patients with Stage III GC, those without HER2 expression survived longer with adjuvant chemotherapy (median 43.9 vs 32.2 months, respectively; P=0.04), whereas those with HER2 expression did not (median 37.1 vs 33.9 months, respectively; P=0.67).

Conclusion

HER2 expression is independently associated with OS in GC, especially in patients who are at higher risk and receive adjuvant chemotherapy after curative resection. HER2 expression may have important clinical utility in directing adjuvant treatment for Stage III GC patients.

Conversion therapy for unresectable gastric cancer

Unresectable gastric cancer cases are often diagnosed at a far advanced stage, which are hard to resect radically and suffer a poor prognosis. Therefore, palliative chemotherapy is recommended as the main treatment by the current clinical guidelines for gastric cancer. Fortunately, in recent years some clinical studies revealed that after treatment with chemotherapy, radiotherapy, targeted therapy, interventional therapy, hyperthermic intraperitoneal chemotherapy (HIPEC) and so on, and multidisciplinary assessment, many unresectable gastric cancer cases could be converted into resectable cases, which consequently prolongs their survival time and improves their quality of life significantly. In the present review, we summarize the status and progress of treatment for unresectable gastric cancer, as well as the strategy and case selection for conversion therapy.

The Efficacy of Taxanes- and Oxaliplatin-Based Chemotherapy in the Treatment of Gastric Cancer After D2 Gastrectomy for Different Lauren Types

To investigate the efficacy of Taxanes- and Oxaliplatin-based chemotherapies (TC and OC) in the treatment of gastric cancer patients after D2 gastrectomy with different Lauren types. In this study, 299 patients of gastric adenocarcinoma with D2 lymph node dissection were reviewed between 2007 and 2014. Chemotherapies were classified as Oxaliplatin-based and Taxanes-based regimen. Treatment outcomes were analyzed according to different Lauren types, such as the intestinal type, diffuse type, and mixed type groups, respectively. The disease-free survival (DFS) and overall survival (OS) were estimated using the Kaplan-Meier method. The log-rank test was used for univariate analysis, and Cox regression was used for multivariate analysis. In diffuse type gastric cancer, the Oxaliplatin-based arm had a longer median DFS and OS compared with Taxanes-based arm (DFS: 47.0 vs 28.6 months, P = 0.04; OS: 51.9 vs 34.5 months, P = 0.048). The chemotherapy regimen was an independent prognostic factor for DFS and OS of diffuse type gastric cancer patients by multivariate analysis (P = 0.01). In the intestinal type, although the DFS and OS of intestinal type patients in TC group were higher than those in OC group (DFS: 53.4 vs 42.4 months; OS: 69.7 vs 57.8 months), there was no statistical significance observed (both P > 0.05). For the mixed type, the 2 different chemotherapy regimens achieved similar median DFS and OS. In a conclusion, the patients of diffuse type were more sensitive to OC, and the intestinal type patients may be benefit from TC. Therefore, it will be of benefit for gastric patients by introducing Lauren classification clinically and to help the choice of chemotherapy regimen for gastric patients after D2 gastrectomy.

Upregulated long intergenic noncoding RNA KRT18P55 acts as a novel biomarker for the progression of intestinal-type gastric cancer

Background

Long noncoding RNAs (lncRNAs) with dysregulated expression levels have been investigated in numerous types of different cancer. Whether lncRNAs can predict the progression of gastric cancer (GC) still remains largely unclear. The aim of our study was to investigate whether KRT18P55, a novel intergenic lncRNA, can be a predictive biomarker for GC.

Methods

To determine the expression levels of KRT18P55 in GC, we evaluated it in five GC cell lines (SGC-7901, MGC-803, BGC-823, AGS, and HG27) and 97 GC tissue samples in comparison with a normal control by quantitative polymerase chain reaction. In addition, the association with patient clinicopathological characteristics was analyzed to identify the clinical significance of KRT18P55. We also used publicly accessible data from The Cancer Genome Atlas (TCGA) to further verify the expression levels and clinical significance of KRT18P55. Furthermore, a receiver operating characteristic curve was also conducted to evaluate the diagnostic value of KRT18P55 for GC.

Results

A significant upregulation was observed in GC cell lines (P<0.01) and tissue samples (P<0.01). This finding was consistent with the results of 29 pairs of GC tissue samples from TCGA (P<0.01). Additionally, we indicated that the increased expression of KRT18P55 was related to the progression of intestinal type (P=0.032), which was also supported by results of independent GC cohorts from TCGA (P<0.01). However, we did not find significant difference in prognosis between patients with high and low expression of KRT18P55 (P>0.05). Finally, KRT18P55 showed potential diagnostic value for GC with an area under the receiver operating characteristic curve of 0.733 (P<0.01).

Conclusion

Upregulated KRT18P55 was a novel biomarker for the progression of GC, especially for the intestinal type.

Clinicopathological Variation of Lauren Classification in Gastric Cancer

The investigation of prognostic factor for gastric cancer is still desirable because of dismal prognosis in gastric cancer. Lauren's classification is currently a useful histological classification. There are few large series evaluating the prognostic significance of Lauren's classification in gastric cancer. From January 1987 to December 2013, a total of 3071 patients received gastrectomy for gastric cancer. According Lauren's classification, 1423(46.3%) patients were intestinal type, 1000 patients (32.6%) were diffuse type, and 648 patients (21.1%) were mixed type. The clinicopathological characteristics and prognosis in Lauren's classification were analyzed in these patients. Our results showed that patients with intestinal type gastric cancer (57.7%) had a better 5-year overall survival than diffuse type (45.6%) and mixed type (43.4%, P < 0.001). The clinicopathological characteristics showed that gastric cancer patients with intestinal type were older (P < 0.001), male predominant (P < 0.001), smaller tumor size (P < 0.001), distal stomach predominant (P < 0.001), relative well differentiated (P < 0.001), less advanced Borrmann type (P < 0.001), less scirrhous type stromal reaction(P < 0.001), less infiltrating type of Ming's histology type(P < 0.001), less tumor invasion depth and less lymphovascular invasion (P < 0.001). Multivariate analysis with overall survival as an endpoint showed that age (P = 0.005), Borrmann classification (P < 0.001), pathological T category (P = 0.023), pathological N category (P < 0.001) and Lauren's classification (P = 0.003) were significant correlated in gastric cancer. Lauren's classification is an independent prognostic factor in gastric cancer patient undergoing gastrectomy. Lauren's classification can serve as a prognostic marker for gastric cancer patient receiving gastrectomy. The clinicopathological appearance and prognosis of mixed type gastric cancer is similar to diffuse type gastric cancer.

A Retrospective Analysis for Patients with HER2-Positive Gastric Cancer Who Were Treated with Trastuzumab-Based Chemotherapy: In the Perspectives of Ethnicity and Histology

PURPOSE

While the Trastuzumab for Gastric Cancer (ToGA) trial demonstrated the efficacy and safety of trastuzumab-based chemotherapy in HER2-positive metastatic gastric cancer, the overall survival (OS) benefit was not found in Asian and diffuse-type cancer patients. The aim of the study is to investigate predictive markers for trastuzumab-based chemotherapy.

MATERIALS AND METHODS

Data of patients with HER2-positive gastric cancer treated with trastuzumab-based chemotherapy were analyzed retrospectively.

RESULTS

A total of 168 Asian patients were included. The median age was 60 years (range, 27 to 85 years) and the male:female ratio was 118 (70.2%):50 (29.8%). Fourteen (8.3%), 63 (37.5%), 75 (44.6%), and 11 (6.5%) patients had well, moderately, poorly-differentiated tubular adenocarcinoma and signet ring cell carcinoma, respectively. With 14 complete responses and 73 partial responses, the response rate was 50.6%. The median progression-free survival (PFS) was 10.2 months (95% confidence interval [CI], 8.7 to 11.7), and the median OS was 18.5 months (95% CI, 16.4 to 50.6). Next, we investigated the effect of poorly-differentiated histology (PDH, poorly-differentiated tubular adenocarcinoma+signet ring cell carcinoma) on clinical outcomes. The median PFS (8.9 months vs. 11.5 months, p=0.16) was slightly inferior in PDH patients, and the median OS was significantly shorter in PDH patients (14.6 months vs. 19.0 months, p=0.025).

CONCLUSION

While subset analysis of the ToGA trial demonstrated that trastuzumab-based chemotherapy may not be beneficial for Asians and patients with PDH, our data may suggest that even in Asian patients and patients with PDH, trastuzumab-based chemotherapy could be associated with improved clinical outcomes in patients with HER2-positive gastric cancer.