The National Cancer Data Base Report on poor survival of U.S. gastric carcinoma patients treated with gastrectomy: Fifth Edition American Joint Committee on Cancer staging, proximal disease, and the "different disease" hypothesis

A 3-MicroRNA Signature Identified From Serum Predicts Clinical Outcome of the Locally Advanced Gastric Cancer

Background: Current staging systems are inadequate for evaluating the prognosis of patients with locally advanced gastric cancer (LAGC, stages II–III). Therefore, we developed a serum microRNA (miRNA) signature to facilitate individualized management of these patients.

Methods: Using microarray analysis, we analyzed 12 serum specimens based on different prognoses (good survival group, n = 7; poor survival group, n = 5). We identified and confirmed differential expression of these miRNAs using quantitative reverse transcription PCR (qRT-PCR) of serum from 51 patients with LAGC. A three miRNA-based classifier was established as a training set by Cox proportional hazard regression and risk-score analysis. We validated the prognostic accuracy of this model in an internal validation cohort (Sun Yat-Sen University Cancer Center, SYSUCC validation cohort, n = 50) and an external independent cohort (Beijing Cancer Hospital, BJCH cohort, n = 67).

Results: Three miRNAs were found to be associated with survival of LAGC (P < 0.001 for miR-132, P = 0.011 for miR-548a-3p, and P < 0.001 for miR-1826). A three-miRNA signature was developed for the training set, and a significant difference was found between the survival of low- and high-risk score patients (P < 0.01). The combination of the miRNA signature and tumor–node–metastasis (TNM) stage exhibited superior discrimination. Consistent results were obtained by further validation of the internal set and the BJCH set, which confirmed the predictive value of the model.

Conclusions: We built an easy-to-use prognostic signature using three serum miRNAs as markers. Our miRNA signature may improve postoperative risk stratification and serve as a complement to the TNM staging system.

Survival in gastric cancer in relation to postoperative adjuvant therapy and determinants

AIM: To evaluate survival data in patients with gastric cancer in relation to postoperative adjuvant therapy and survival determinants

METHODS: A total of 201 patients (mean ± SD age: 56.0 ± 11.9 years, 69.7% were males) with gastric carcinoma who were operated and followed up at Lutfi Kirdar Kartal Training and Research Hospital between 1998 and 2010 were included in this retrospective study. Follow up was evaluated divided into two consecutive periods (before 2008 and 2008-2010, respectively) based on introduction of 3-D conformal technique in radiotherapy at our clinic in 2008. Data on patient demographics, clinical and histopathological characteristics of gastric carcinoma and the type of treatment applied after surgery [postoperative adjuvant treatment protocols including chemoradiotherapy (CRT) and chemotherapy (CT), supportive therapy or follow up without any treatment] were recorded. The median duration and determinants of local recurrence free (LRF) survival, distant metastasis free (DMF) survival and overall survival were evaluated in the overall population as well as with respect to follow up years [1998-2008 (n = 127) vs 2008-2010 (n = 74)].

RESULTS: Median duration for LRF survival, DMF survival and overall survival were 31.9, 24.1 and 31.9 mo, respectively in patients with postoperative adjuvant CRT. No significant difference was noted in median duration for LRF survival, DMF survival and overall survival with respect to treatment protocols in the overall population and also with respect to followed up periods. In the overall population, CT protocols FUFA [5-fluorouracil (400 mg/m²) and leucovorin-folinic acid (FA, 20 mg/m²)] (29.9 mo) and UFT^® + Antrex^® [a fixed combination of the oral FU prodrug tegafur (flouroprymidine, FT, 300 mg/m² per day) with FA (Antrex^®), 15 mg tablet, two times a day] (42.5 mo) was significantly associated with longer LRF survival times than other CT protocols (P = 0.036), while no difference was noted between CT protocols in terms of DMF survival and overall survival. Among patients received CRT, overall survival was significantly longer in patients with negative than positive surgical margin (27.7 mo vs 22.4 mo, P = 0.016) in the overall study population, while time of radiotherapy initiation had no significant impact on survival times. Nodal stage was determined to be independent predictor of LRF survival in the overall study population with 4.959 fold (P = 0.042) increase in mortality in patients with nodal stage N2 compared to patients with nodal stage N0, and independent predictor of overall survival with 5.132 fold (P = 0.006), 5.263 fold (P = 0.027) and 4.056 fold (P = 0.009) increase in the mortality in patients with nodal stage N3a (before 2008), N3b (before 2008) and N2 (overall study population) when compared to patients with N0 stage, respectively.

CONCLUSION: Our findings emphasize the likelihood of postoperative adjuvant CRT to have a survival benefit in patients with resectable gastric carcinoma.

Gastric cancer arising from the remnant stomach after distal gastrectomy: A review

Gastric stump carcinoma was initially reported by Balfore in 1922, and many reports of this disease have since been published. We herein review previous reports of gastric stump carcinoma with respect to epidemiology, carcinogenesis, Helicobacter pylori (H. pylori) infection, Epstein-Barr virus infection, clinicopathologic characteristics and endoscopic treatment. In particular, it is noteworthy that no prognostic differences are observed between gastric stump carcinoma and primary upper third gastric cancer. In addition, endoscopic submucosal dissection has recently been used to treat gastric stump carcinoma in the early stage. In contrast, many issues concerning gastric stump carcinoma remain to be clarified, including molecular biological characteristics and the carcinogenesis of H. pylori infection. We herein review the previous pertinent literature and summarize the characteristics of gastric stump carcinoma reported to date.

Semaphorin 5A promotes gastric cancer invasion/metastasis via urokinase-type plasminogen activator/phosphoinositide 3-kinase/protein kinase B

BACKGROUND

Semaphorin 5A, a member of the semaphorin family, was originally identified as an axonal guidance factor functioning during neuronal development. Previously, we showed that the expression of semaphorin 5A might contribute to the metastasis of gastric cancer. However, less information is currently available as to the involvement of uPA in the semaphorin 5A-induced metastasis and invasion of gastric cancer cells.

AIM

The present study was designed to test whether semaphorin 5A mediates the invasion and metastasis of gastric cancer via PI3K/Akt/uPA signaling.

METHODS

The semaphorin 5A-overexpressing cell was established from the gastric cancer cell line AGS. The effect of semaphorin 5A on the expression of uPA was evaluated by ELISA and Western blotting as well as RT-PCR assays, respectively. Synthetic or natural inhibitors and dominant-negative mutants were used to determine the hierarchical relationship between semaphorin 5A, PI3K/Akt and uPA in the invasion and metastasis of gastric cancer.

RESULTS

Overpression of semaphorin 5A enhanced the expression of uPA, and synthetic or natural inhibitors of uPA abolished semaphorin 5A-induced cell migration and invasion. Semaphorin 5A overexpression promoted the phosphorylation of Akt. Blocking effects of PI3K/Akt using pharmacologic inhibitors, dominant-negative mutants abolished the ability of semaphorin 5A to induce uPA expression and cell invasion and migration.

CONCLUSION

Semaphorin 5A could promote invasion and metastasis of gastric cancer through the PI3K/Akt/uPA signal transduction pathway. Semaphorin 5A and its regulated molecules could be the potential targets for cancer therapy.

Treatment of gastric adenocarcinoma may differ among hospital types in the United States, a report from theNational Cancer Data Base

The concept that complex surgical procedures should be performed at high-volume centers to improve surgical morbidity and mortality is becoming widely accepted. We wanted to determine if there were differences in the treatment of patients with gastric cancer between community cancer centers and teaching hospitals in the United States. Data from the 2001 Gastric Cancer Patient Care Evaluation Study of the National Cancer Data Base comprising 6,047 patients with gastric adenocarcinoma treated at 691 hospitals were assessed. The mean number of patients treated was larger at teaching hospitals (14/year) when compared to community centers (5-9/year) (p<0.05). The utilization of laparoscopy and endoscopic ultrasonography were significantly more common at teaching centers (p<0.01). Pathologic assessment of greater than 15 nodes was documented in 31% of specimen at community hospitals and 38% at teaching hospitals (p<0.01). Adjusted for cancer stage, chemotherapy and radiation therapy were utilized with equal frequency at all types of treatment centers. The 30-day postoperative mortality was lowest at teaching hospitals (5.5%) and highest at community hospitals (9.9%) (p<0.01). These data support previous publications demonstrating that patients with diseases requiring specialized treatment have lower operative mortality when treated at high-volume centers.