The clinicopathological features of gastric cancer (GC) differ between younger and older patients, and it is thought that younger patients have a worse prognosis than older patients due to delayed diagnosis and more aggressive tumor behavior. These characteristics, however, remain controversial. A total of 3,818 patients with pathologically confirmed primary gastric adenocarcinoma were treated at our institution. We analyzed the difference in demographic and clinicopathological characteristics between 169 young [≤40 years of age, younger group (YG)] and 3,649 older [>40 years of age, older group (OG)] GC patients. There was a significantly higher proportion of females in the YG compared with the OG (53.3 and 31.0%, respectively; P<0.0001). The 5-year overall survival of the YG was significantly lower compared to that of the OG (59.7 and 65.9%, respectively; P=0.049). However, YG patients with curative resection had a similar 5-year survival rate to OG patients with curative resection (88.0 and 85.8%, respectively; P=0.547). Female patients in the YG showed a significantly lower survival rate than males in the YG (44.3 and 73.1%, respectively; P=0.0002). Multivariate analyses revealed that macroscopic type, depth of invasion, peritoneal metastasis, distant metastasis and curative resection were independent prognostic factors for the YG with GC. Young GC patients who undergo curative resection do not have a worse prognosis than older patients. Early diagnosis is important in successfully carrying out a curative resection and offering a better prognosis, particularly in females.

BackgroundCD133 is one of the most important stem cell markers in solid cancers. Some recent reports have described a possible relationship between CD133 and hypoxia-inducing factor-1-alpha (HIF-1α). The aim of this study was to clarify the clinical role of CD133 expression in gastric cancer and to investigate the correlation between CD133 expression and HIF-1α expression.MethodsWe studied 189 gastric cancer patients who underwent gastrectomy at Kurume University Hospital. CD133 and HIF-1α expression was examined using immunohistochemical staining. Fifty-six cases were CD133 positive, and they were divided into two expression types: luminal expression of the gland and cytoplasmic expression. We investigated the relationship among CD133 expression types, clinicopathological variables, prognosis, and HIF-1α expression.ResultsWhen comparing clinicopathological variables, expression of CD133 in the cytoplasm was related to metastasis and tumor progression. However, this relationship was not observed with luminal expression of the gland type. The survival rate in patients with cytoplasmic CD133 expression was significantly worse than that in the CD133-negative group. This relationship was observed in the survival rate of the adjuvant chemotherapy group and the curative resection group. Multivariate analysis revealed that the expression of CD133 in the cytoplasm was an independent prognostic factor in gastric cancer. Regarding the correlation between CD133 expression and HIF-1α expression, the HIF-1α positive rate was lower in patients with CD133 luminal expression of the gland type and higher in patients with cytoplasmic expression of CD133.ConclusionGastric cancer cells with CD133 expression in the cytoplasm were cells with high potential for malignancy, and this phenotype was associated with cancer progression, chemotherapy resistance, recurrence, and poor prognosis. Cytoplasmic expression of CD133 may be a useful prognostic marker in gastric cancer. Significant correlation was observed between HIF-1α expression and the immunohistochemical staining pattern of CD133.

A careful preoperative endoscopy is necessary for patients who are at high risk of SMGC, and minimally invasive treatment may be indicated in some cases.

Proximal gastrectomy (PG) is a widely accepted, efficient treatment for upper-third early gastric cancer. However, it is associated with reduced quality of life (QOL) following surgery, and cancer recurrence in the remaining stomach. Various reconstruction methods have been proposed, but the optimal method has yet to be determined. We investigated the clinicopathological characteristics, reconstruction methods, and postoperative complications in 101 cases of PG, and additionally compared 93 cases of early gastric cancer treated by PG, and 38 cases treated by total gastrectomy (TG). We found that esophagogastrostomy was superior in terms of operation time, intraoperative blood loss, and postoperative hospital stay, while no significant differences were observed in postoperative complications compared with jejunal interposition or jejunal pouch interposition. We found more cases of multiple gastric cancers and advanced-stage cancer in the TG group than in the PG group. The TG group also had a significantly higher proportion of cases with large tumor diameters, low degrees of differentiation, many lymph node metastases, and advanced-stage disease. There were no differences in the recurrence rate or survival rate between the PG and TG groups. The PG group also showed significantly better results in operating time, intraoperative blood loss, and postoperative complications, with a tendency toward shorter hospital stays. In conclusion, PG is a curative but less invasive treatment for upper-third early gastric cancer, and esophagogastrostomy can be considered the most satisfactory reconstruction method following PG.

Trastuzumab that targets human epidermal growth factor receptor 2 (HER2) protein is the only approved molecular targeting agent for treating gastric cancer in Japan and the outcomes have been favorable. However, trastuzumab is effective for only 10% to 20% of the population with gastric cancer that expresses HER2 protein. Molecular targeting therapy with bevacizumab against vascular endothelial growth factors (VEGF) and with cetuximab and panitumumab against the epidermal growth factors pathway that have been approved for treating colorectal cancer are not considered effective for treating gastric cancer according to several clinical trials. However, ramucirumab that targets VEGF receptor-2 prolonged overall survival in a large phase III clinical trial and it might be an effective molecular targeting therapy for gastric cancer. The significance of molecular targeting therapy for gastric cancer remains controversial. A large-scale randomized clinical trial of novel molecular targeting agents with which to treat gastric cancer is needed.