Carrier Mobility Enhancement of Tensile Strained Si and SiGe Nanowires via Surface Defect Engineering

Changes in the carrier mobility of tensile strained Si and SiGe nanowires (NWs) were examined using an electrical push-to-pull device (E-PTP, Hysitron). The changes were found to be closely related to the chemical structure at the surface, likely defect states. As tensile strain is increased, the resistivity of SiGe NWs deceases in a linear manner. However, the corresponding values for Si NWs increased with increasing tensile strain, which is closely related to broken bonds induced by defects at the NW surface. Broken bonds at the surface, which communicate with the defect state of Si are critically altered when Ge is incorporated in Si NW. In addition, the number of defects could be significantly decreased in Si NWs by incorporating a surface passivated Al2O3 layer, which removes broken bonds, resulting in a proportional decrease in the resistivity of Si NWs with increasing strain. Moreover, the presence of a passivation layer dramatically increases the extent of fracture strain in NWs, and a significant enhancement in mobility of about 2.6 times was observed for a tensile strain of 5.7%.

Techniques of the Single-Port Totally Laparoscopic Distal Gastrectomy

BACKGROUND

Single-port laparoscopic surgery for patients with early gastric cancer has been rarely reported. Our aim was to introduce techniques of the single-port totally laparoscopic distal gastrectomy (TLDG) in patients with early gastric cancer.

METHODS

This procedure was performed using only one 3-3.5 cm skin incision on the umbilicus. One 12 mm and two 10 mm ports were used, and the flexible scope was used during the operation. Partial omentectomy with D1 + β or more lymph node dissection was performed. Bowel continuity was restored by intracorporeal gastroduodenostomy using two linear staplers.

RESULTS

A total of 30 patients underwent single-port TLDG from June to August 2014. Median age of patients was 55 years (range 33-77) and median body mass index of patients was 21.2 kg/m(2) (range 15.7-26.1). Sixteen of 30 patients (53.3 %) were female. Operating times were 122.6 min, and blood losses during operations were 103.2 ml on average. The median length of postoperative hospital stay was 7 days, and the median number of dissected lymph nodes was 40 (range 16-67). No patients had dissected lymph nodes <15. The rate of complications was 20 % (6/30 patients), and no patients had an incisional hernia. Two patients experienced ileus (6.7 %), another two patients experienced delayed gastric emptying (6.7 %), and one patient suffered from small bowel obstruction. There were no postoperative mortalities.

CONCLUSIONS

The single-port TLDG for patients with early gastric cancer is feasible in very selected patients and in specialized gastric cancer centers with experience in multi-trocar laparoscopy and single-port laparoscopic surgery.

Phase III Trial to Compare Adjuvant Chemotherapy With Capecitabine and Cisplatin Versus Concurrent Chemoradiotherapy in Gastric Cancer: Final Report of the Adjuvant Chemoradiotherapy in Stomach Tumors Trial, Including Survival and Subset Analyses

Purpose

The Adjuvant Chemoradiotherapy in Stomach Tumors (ARTIST) trial tested whether the addition of radiotherapy to adjuvant chemotherapy improved disease-free survival (DFS) in patients with D2-resected gastric cancer (GC).

Patients and Methods

Between November 2004 and April 2008, 458 patients with GC who received gastrectomy with D2 lymph node dissection were randomly assigned to either six cycles of adjuvant chemotherapy with capecitabine and cisplatin (XP) or to two cycles of XP followed by chemoradiotherapy and then two additional cycles of XP (XPRT). This final update contains the first publication of overall survival (OS), together with updated DFS and subset analyses.

Results

With 7 years of follow-up, DFS remained similar between treatment arms (hazard ratio [HR], 0.740; 95% CI, 0.520 to 1.050; P = .0922). OS also was similar (HR, 1.130; 95% CI, 0.775 to 1.647; P = .5272). The effect of the addition of radiotherapy on DFS and OS differed by Lauren classification (interaction P = .04 for DFS; interaction P = .03 for OS) and lymph node ratio (interaction P < .01 for DFS; interaction P < .01 for OS). Subgroup analyses also showed that chemoradiotherapy significantly improved DFS in patients with node-positive disease and with intestinal-type GC. There was a similar trend for DFS and OS by stage of disease.

Conclusion

In D2-resected GC, both adjuvant chemotherapy and chemoradiotherapy are tolerated and equally beneficial in preventing relapse. Because results suggest a significant DFS effect of chemoradiotherapy in subsets of patients, the ARTIST 2 trial evaluating adjuvant chemotherapy and chemoradiotherapy in patients with node-positive, D2-resected GC is under way.

Preoperative smoking cessation can reduce postoperative complications in gastric cancer surgery

BACKGROUND

Despite the close link between cigarette smoking and the development of gastric cancer, little is known about the effects of cigarette smoking on surgical outcomes after gastric cancer surgery. The aim of this study was to investigate whether preoperative smoking status and the duration of smoking cessation were associated with short-term surgical consequences in gastric cancer surgery.

METHODS

Among 1,489 consecutive patients, 1,335 patients who underwent curative radical gastrectomy at the Samsung Medical Center between January and December 2009 were included in the present study. The smoking status was determined using questionnaires before surgery. Smokers were divided into four groups according to the duration of smoking cessation preoperatively (<2, 2-4, 4-8, and >8 weeks). The primary endpoint was postoperative complications (wound, lung, leakage, and bleeding); secondary endpoints were 3-year recurrence-free survival (RFS) and overall survival (OS).

RESULTS

Five hundred twenty-two patients (39.1 %) were smokers. Smokers had a significantly higher overall incidence of postoperative complications than nonsmokers (12.3 vs. 5.2 %, P < 0.001, respectively), especially in impaired wound healing, pulmonary problems, and leakage. Smokers also had more severe complications than nonsmokers. After adjusting for other risk factors, the odds ratio (95 % CI) for the development of postoperative complications in the subgroups who stopped smoking <2 weeks, 2-4, 4-8, and >8 weeks preoperatively were 3.35 (1.92-5.83), 0.99 (0.22-4.38), 2.18 (1.00-4.76), and 1.32 (0.70-2.48), respectively, compared with the nonsmokers. There were no significant differences in 3-year RFS (P = 0.884) and OS (P = 0.258) between smokers and nonsmokers.

CONCLUSIONS

Preoperative smoking cessation for at least 2 weeks will help to reduce the incidence of postoperative complications in gastric cancer surgery.

Clinical Significance of IGFBP-3 Methylation in Patients with Early Stage Gastric Cancer

BACKGROUND: IGFBP-3 is a multifunctional protein that inhibits growth and induces apoptosis of cancer cells. Hypermethylation of the promoter represses expression of the IGFBP-3 gene. We undertook this study to assess the impact of IGFBP-3 methylation on survival of early stage gastric cancer patients. METHODS: Of the 482 tissue samples from gastric cancer patients who underwent curative surgery, IGFBP-3 methylation was tested in 138 patients with stage IB/II gastric cancer. We also analyzed IGFBP-3 methylation in 26 gastric cancer cell lines. IGFBP-3 methylation was evaluated by methylation-specific polymerase chain reaction (MethyLight). Statistical analyses, all two-sided, were performed to investigate the prognostic effects of methylation status of the IGFBP-3 promoter on various clinical parameters. RESULTS: Hypermethylation of IGFBP-3 was observed in 26 (19%) of the 138 stage IB/II gastric cancer patients. Clinicopathological factors such as age, Lauren classification, sex, tumor infiltration, lymph node metastasis, and histologic grade did not show a statistically significant association with the methylation status of the IGFBP-3 promoter. Patients with a hypermethylated IGFBP-3 promoter had similar 8-year disease-free survival compared with those without a hypermethylated IGFBP-3 promoter (73% vs 75%, P = .78). In subgroup analyses, females, but not males, seemed to have poorer prognosis for DFS and OS in the subset of patients with IGFBP-3 methylation as compared with those without IGFBP-3 methylation (8-year DFS: 55.6% vs 71.6%, P = .3694 and 8-year overall survival: 55.6% vs 68.4%, P = .491, respectively) even with no statistical significance. CONCLUSIONS: The status of IGFBP-3 methylation as measured by methylation-specific polymerase chain reaction proposed the modest role for predicting survival in specific subgroups of patients with early-stage gastric cancer who undergo curative surgery. However, this needs further investigation.

Effects of adjuvant radiotherapy on completely resected gastric cancer: A radiation oncologist's view of the ARTIST randomized phase III trial

PURPOSE

We investigated which subgroups might benefit from adjuvant radiotherapy (RT) and suggested optimal RT targets by analyzing the results of the Adjuvant Chemoradiation Therapy in Stomach Cancer (ARTIST) trial.

METHODS

We conducted randomized controlled trial in 458 gastric cancer patients. Patients were randomly assigned to XP (6 cycles of capecitabine and) or XPRT (2 cycles of XP+RT 45Gy/25 fraction with capecitabine+2 cycles of XP) groups after D2 resection. Minimum follow-up was 5years.

RESULTS

During follow-up, 77 patients (33.8%) in the XP arm and 60 (26.1%) in the XPRT arm experienced recurrence. Among these patients, locoregional recurrence (LRR) developed in 44 (9.6%; 29 in XP, 15 in XPRT; P=0.03). The local recurrence rate (4.8%) did not vary between arms. Regional recurrence was the most important difference between the two groups (23 in the XP arm, 5 in the XPRT arm, P<0.001). LRR-free survival (LRRFS) was significantly different between study arms (P=0.03), especially in patients with LN metastasis (P=0.009).

CONCLUSIONS

Adjuvant RT after D2 resection in gastric cancer reduced LRR, especially in group 3 LNs, and improved LRRFS. Patients with LN metastasis benefited more from the adjuvant RT treatment than the other subgroups.

Molecular analysis of gastric cancer identifies subtypes associated with distinct clinical outcomes

Gastric cancer, a leading cause of cancer-related deaths, is a heterogeneous disease. We aim to establish clinically relevant molecular subtypes that would encompass this heterogeneity and provide useful clinical information. We use gene expression data to describe four molecular subtypes linked to distinct patterns of molecular alterations, disease progression and prognosis. The mesenchymal-like type includes diffuse-subtype tumors with the worst prognosis, the tendency to occur at an earlier age and the highest recurrence frequency (63%) of the four subtypes. Microsatellite-unstable tumors are hyper-mutated intestinal-subtype tumors occurring in the antrum; these have the best overall prognosis and the lowest frequency of recurrence (22%) of the four subtypes. The tumor protein 53 (TP53)-active and TP53-inactive types include patients with intermediate prognosis and recurrence rates (with respect to the other two subtypes), with the TP53-active group showing better prognosis. We describe key molecular alterations in each of the four subtypes using targeted sequencing and genome-wide copy number microarrays. We validate these subtypes in independent cohorts in order to provide a consistent and unified framework for further clinical and preclinical translational research.

Gastric duplication cysts in adults: a report of three cases

Gastric duplication cyst is a rare congenital anomaly of the gastrointestinal tract and is especially uncommon in adults. Most cases in adults are discovered incidentally on radiological examination or gastric endoscopy. Accurate diagnosis of these cysts before resection is difficult. Differential diagnoses are varied. Malignant transformation of a gastric duplication cyst is very rare. We present three cases of asymptomatic noncommunicating gastric duplication cysts in adults.

Ultrasonically activated shears versus electrocautery in open gastrectomy for gastric cancer: a randomized controlled trial

BACKGROUND

Use of ultrasonically activated shears (UAS) is gaining popularity in open surgery but without concrete evidence. We conducted a prospectively randomized study to assess the efficacy of ultrasonic dissection in open gastrectomy for gastric cancer.

METHODS

Patients with gastric cancer who were to undergo gastrectomy with D2 lymph node dissection were enrolled and assigned to either the conventional surgery group (n = 125) or the UAS group (n = 128).

RESULTS

The mean operating time was significantly reduced in the UAS group (89.3 ± 15.6 min) when compared to the conventional group (97.8 ± 17.2 min; p < 0.001). However, we did not find any significant difference in operative blood loss, the amount of postoperative abdominal drainage, or the rate of postoperative complications between the groups. A multivariate analysis for operating time revealed that the use of UAS, female gender and BMI less than 25 were significantly associated with reduced operating time. The operating time was significantly longer in the conventional group than in the UAS group (B 7.786; 95 % CI 4.103-11.468; p < 0.001). In the subgroup analysis, the use of UAS significantly reduced the operating time, especially in male patients, regardless of the BMI status.

CONCLUSIONS

The use of UAS in gastrectomy for gastric cancer was a safe and efficient method, especially in terms of reducing operating time for male patients.

Comparison of Reduced Port Totally Laparoscopic Distal Gastrectomy (Duet TLDG) and Conventional Laparoscopic-Assisted Distal Gastrectomy

BACKGROUND

Laparoscopic-assisted distal gastrectomy (LADG) is a treatment method for patients with early gastric cancer; however, single or reduced port LADG has been rarely reported. This study aimed to compare surgical outcomes of patients with gastric cancer undergoing reduced port totally laparoscopic distal gastrectomy (duet TLDG) to those of patients undergoing conventional LADG.

METHODS

This retrospective study included 202 patients with early gastric cancer who underwent duet TLDG (102 patients) or conventional LADG (100 patients) at Samsung Medical Center between October 2013 and April 2014.

RESULTS

Operating time was shorter for duet TLDG than for conventional LADG (mean ± SD 121.1 ± 19.3 min vs. 153.0 ± 38.1 min, P < 0.001). Blood loss during surgery was similar between duet TLDG and conventional LADG groups (91.4 ± 68.4 mL vs. 85.4 ± 59.8 mL, P = 0.506). Complication rates in the duet TLDG and conventional LADG groups were similar (15.7 % vs. 10.0 %, P = 0.294). The quality of lymph node dissection, including the median number of nodes dissected (median [range] duet TLDG vs. conventional LADG, 36 [17-76] vs. 34 [15-64], P = 0.570) and number of dissected nodes in each lymph node station, did not differ between groups. The median postoperative hospital stay was similar (7 [7-23] days vs. 7 [6-9], P = 0.423). Pain scores were 3.6, 3.2, and 2.8, and 3.7, 3.1, and 2.6, at postoperative days 1, 3, and 5, respectively, in the duet TLDG and conventional LADG groups (P = 0.408, 0.250, and 0.130).

CONCLUSIONS

Reduced port duet TLDG for early gastric cancer is feasible in terms of patient safety and quality of lymph node dissection.

Lymphoepithelioma-like carcinoma: a distinct type of gastric cancer

BACKGROUND

Lymphoepithelioma-like carcinoma (LELC) is a rare type of gastric carcinoma and has histologic features of intense lymphocytic infiltration. In this study, we attempted to analyze the clinicopathologic characteristics and survival outcome of patients with LELC compared with those with non-lymphoepithelioma-like carcinoma (NLELC).

METHODS

We studied 4282 patients who underwent gastrectomies to treat gastric cancer at the Department of Surgery of the Samsung Medical Center in Seoul, between January 2008 and December 2010. The clinicopathologic features and clinical outcomes of patients with LELC (n = 46) were compared with those with NLELC (n = 4236). In situ hybridization for Epstein-Barr virus (EBV) positivity was performed on the tissue of patients with LELC (n = 46) and NLELC (n = 1247).

RESULTS

The patients with LELC are male predominant and had more upper locations, more indeterminate Lauren classifications, lower T stages, less lymphatic invasion, and more positive EBV in situ hybridization compared with those of the NLELC group (80.4% versus 6.5%). Age, histologic type, Lauren type, the location of the tumor, the depth of the invasion, lymph node metastasis, and venous invasion were independent prognostic factors; however, the LELC type itself was not predictive of outcome. The 5-y survival rate of the LELC group (97.7%) was better than that of the NLELC group (89.4%); however, this difference was not statistically significant (P = 0.127).

CONCLUSIONS

The results of our study suggest that LELC is a less advanced disease than NLELC in terms of depth of invasion and lymphatic invasion at diagnosis. However, our study does not examine LELC as an independent prognostic factor of gastric cancer. Further studies are needed to explore its associations with EBV and a distinct pathway of carcinogenesis from NLELC.

Effect of triclosan-coated sutures on surgical site infection after gastric cancer surgery via midline laparotomy

PURPOSE

Surgical site infection (SSI) after open abdominal surgery is still a frequently reported nosocomial infection. To reduce the incidence of SSI, triclosan-coated sutures with antiseptic activity (Vicryl Plus) were developed. The aim of this study was to analyze the effect of Vicryl Plus on SSI after gastric cancer surgery via midline laparotomy.

METHODS

A total of 916 patients who underwent gastric cancer surgery at Samsung Medical Center between December 2009 and September 2011 were prospectively collected. We examined the occurrence of SSI (primary endpoint), assessments of wound healing (secondary endpoint). They were evaluated postoperatively on days 3, 7, and 30.

RESULTS

Of the 916 patients, 122 were excluded postoperatively by screening (out of the study protocol, adverse events, etc.). The remaining 794 patients were enrolled and monitored postoperatively. The cumulative SSI incidence was 11 cases (1.39%; 95% confidence interval [CI], 0.77-2.50) on day 30. Seromas were most frequently detected in wound healing assessments, with a cumulative incidence of 147 cases (18.51%; 95% CI, 15.98-21.39) on day 30.

CONCLUSION

The use of triclosan-coated sutures (Vicryl Plus) for abdominal wall closure can reduce the number of SSIs in gastric cancer surgery.

Clinical significance of skip lymph node metastasis in gastric cancer patients

PURPOSE

Given the recent increase in the incidence of early gastric cancer, there is greater interest in identifying a minimally invasive therapy. The purpose of this study was to analyze the patterns of lymph node metastasis in patients with gastric cancer and to elucidate the clinical significance of skip metastasis.

METHODS

We retrospectively analyzed patterns of lymph node metastasis (LNM) and clinicopathologic factors related to skip metastasis.

RESULTS

Among 2963 patients with gastric cancer, 997 patients (33.6%) were detected as having LNM, and 27 patients (2.7%) with skip metastasis were detected among 997 patients with LNM. Skip metastasis were detected more frequently in the elderly. Compared with the N1 group, the skip metastasis group showed lower frequency of vascular invasion, and compared with the stepwise N2 group, the skip metastasis group showed smaller tumor size and a significantly higher incidence of negative lymphatic, vascular, and perineural invasion.

CONCLUSIONS

Currently there is no way to predict N2 station LNM including skip metastasis, D2 LN dissection for gastric cancer is thought to be the appropriate treatment, even during early stage disease. Minimally invasive therapy should be performed cautiously in consideration of possible skip metastasis.

High-throughput sequencing and copy number variation detection using formalin fixed embedded tissue in metastatic gastric cancer

In the era of targeted therapy, mutation profiling of cancer is a crucial aspect of making therapeutic decisions. To characterize cancer at a molecular level, the use of formalin-fixed paraffin-embedded tissue is important. We tested the Ion AmpliSeq Cancer Hotspot Panel v2 and nCounter Copy Number Variation Assay in 89 formalin-fixed paraffin-embedded gastric cancer samples to determine whether they are applicable in archival clinical samples for personalized targeted therapies. We validated the results with Sanger sequencing, real-time quantitative PCR, fluorescence in situ hybridization and immunohistochemistry. Frequently detected somatic mutations included TP53 (28.17%), APC (10.1%), PIK3CA (5.6%), KRAS (4.5%), SMO (3.4%), STK11 (3.4%), CDKN2A (3.4%) and SMAD4 (3.4%). Amplifications of HER2, CCNE1, MYC, KRAS and EGFR genes were observed in 8 (8.9%), 4 (4.5%), 2 (2.2%), 1 (1.1%) and 1 (1.1%) cases, respectively. In the cases with amplification, fluorescence in situ hybridization for HER2 verified gene amplification and immunohistochemistry for HER2, EGFR and CCNE1 verified the overexpression of proteins in tumor cells. In conclusion, we successfully performed semiconductor-based sequencing and nCounter copy number variation analyses in formalin-fixed paraffin-embedded gastric cancer samples. High-throughput screening in archival clinical samples enables faster, more accurate and cost-effective detection of hotspot mutations or amplification in genes.

Adjuvant chemoradiation with 5-fluorouracil/leucovorin versus S-1 in gastric cancer patients following D2 lymph node dissection surgery: a feasibility study

PURPOSE

We retrospectively analyzed the feasibility and adverse events for two regimens, postoperative chemoradiation (CRT) with 5-fluorouracil/leucovorin (5-FU/LV) compared to S-1 in D2-resected gastric cancer patients.

PATIENTS AND METHODS

The study included 405 gastric cancer patients who underwent curative gastrectomy with D2 lymph node dissection and received adjuvant therapy between January 2008 and July 2009. Feasibility and adverse events for the CRT and S-1 regimens were analyzed.

RESULTS

Out of the 405 patients, 244 (60.2%) had CRT and 161 (39.8%) had S-1 treatment. The regimen was selected based on the preferences of the physician and the patient. S-1 was more frequently administered to patients with older age (age≥70) and those with early-stage disease (stage II). The stage was significantly more advanced in the CRT group compared to the S-1 group (S-1 vs. CRT: stage II, 59.6% vs. 36.1%; stage III/IV, 28.0% vs. 48.3%, respectively; p<0.001). The completion rate of the planned therapy was significantly higher in the CRT group than in the S-1 group (95.1% vs. 72.8%, respectively; p<0.001). Regarding severe adverse events (grade 3-4), neutropenia (CRT vs. S-1; 40.2% vs. 8.7%, respectively, p<0.001), nausea (CRT vs. S-1; 5.7% vs. 0%, respectively; p=0.002) and stomatitis (CRT vs. S-1; 7.4% vs. 2.5%, respectively; p=0.034) were significantly more frequent in the CRT cohort compared to the S-1 group.

CONCLUSION

Both adjuvant CRT with 5-FU/LV and adjuvant S-1 are safe and feasible in D2-resected gastric cancer patients. Patients with old age or early stage disease tend to prefer S-1 therapy to chemoradiation.

Concurrent robot-assisted distal gastrectomy and partial nephrectomy for synchronous early gastric cancer and renal cell carcinoma: an initial experience

We report our experience of a concurrent robot assisted distal gastrectomy and partial nephrectomy for synchronous early gastric cancer and renal cell carcinoma. A 55-year-old female patient was diagnosed with early gastric cancer on screening endoscopy. Abdominal computed tomography showed an incidental right renal cell carcinoma. Robot assisted distal gastrectomy was performed, followed by partial nephrectomy. The final pathological examination showed signet ring cell carcinoma within the lamina propria and renal cell carcinoma with negative resection margins. The patient showed no evidence of recurrence at 6-months. A robot-assisted combined operation could be a treatment option for early stages of synchronous malignancies.

HER2-positive gastric cancer with concomitant MET and/or EGFR overexpression: a distinct subset of patients for dual inhibition therapy

Growth factor receptors, often carrying tyrosine kinase activities in their cytoplasmic domains, are overexpressed in many cancers. Coactivation of receptor tyrosine kinases (RTKs) plays a critical role in tumor response to targeted therapeutics. We examined concomitant overexpression of EGFR and MET in patients with HER2(+) and HER2(-) gastric cancers (GCs). Tissue microarray samples obtained from 1,589 GC patients who received R0 gastrectomy with extensive node dissection and adjuvant chemoradiationtherapy were analyzed by immunohistochemistry and fluorescence in situ hybridization. HER2(+) was observed in 169 patients (11%). Out of 169 HER2(+) patients, 15 (9%) were EGFR(+) and MET(+) , 29 (17%) were EGFR(+) , 37 (22%) were MET(+) and the remaining 88 patients (52%) were HER2(+) only, without concomitant EGFR or MET overexpression. Greater number of overexpressed RTKs correlated with younger age (p < 0.001), larger tumor size (p = 0.027), intestinal histology (p < 0.001) and shorter overall survival (p = 0.002). The mean overall survival was 113 months for HER2(-) /EGFR(-) /MET(-) and 63 months for HER2(+) /EGFR(+) /MET(+) subgroups. Patients with HER2(+) /EGFR(+) /MET(+) GCs had a substantial risk of death with a hazard ratio of 3.01 (95% CI: 1.54-5.90), compared with HER2(-) /EGFR(-) /MET(-) GC patients. Using patient-derived tumor cell models isolated from pericardial effusion of HER2(+) and MET(+) GC cases, we demonstrated that the combination of HER2-inhibitor (lapatinib) and MET-inhibitor offered a more profound inhibition in the ERK/AKT pathway and cell proliferation than lapatinib alone. Co-overexpression of RTKs was demonstrated in small subsets of GC associated with aggressive behavior and in these cases, combination therapy may be considered as potential treatment options.

FAIRY: a randomized controlled patient-blind phase III study to compare the efficacy and safety of intravenous ferric carboxymaltose (Ferinject®) to placebo in patients with acute isovolemic anemia after gastrectomy - study protocol for a randomized controlled trial

Background

Isovolemic anemia (decrease in hemoglobin concentration with normal or even increased blood volume) after gastric cancer surgery may negatively influence short- and long-term outcomes. Therefore correction of isovolemic postoperative anemia is supposed to be beneficial. This prospective randomized placebo-controlled multicenter trial is designed to evaluate the efficacy of ferric carboxymaltose administration with the primary end point of successful hemoglobin level increase by 2 g/dl at 12 weeks after randomization.

Methods and design

Gastric cancer patients after oncologic resection and postoperative hemoglobin level ≥ 7 g/dl to <10 g/dl at postoperative days 5 to 7 will be eligible for trial inclusion. After randomization, 450 patients (225 per group) are going to be subjected either to administration of ferric carboxymaltose (treatment group) or normal (0.9%) saline (placebo group). Patients will be blinded to the intervention. Patients will undergo evaluation for hemoglobin level, hematology and quality of life assessment 3 and 12 weeks after randomization.

Discussion

Correction of isovolemic postoperative anemia in gastric cancer patients after oncologic resection is considered to be beneficial. Administration of ferric carboxymaltose is considered to be superior to placebo for anemia correction without the possible risks of red blood cell transfusion. Further, improved quality of life for patients with quick recovery of hemoglobin levels is expected.

Trial registration

NCT01725789 (international: http://www.clinicaltrials.gov) and NCCCTS-12-644 (NCC, Korea).

Nanostring-based multigene assay to predict recurrence for gastric cancer patients after surgery

Despite the benefits from adjuvant chemotherapy or chemoradiotherapy, approximately one-third of stage II gastric cancer (GC) patients developed recurrences. The aim of this study was to develop and validate a prognostic algorithm for gastric cancer (GCPS) that can robustly identify high-risk group for recurrence among stage II patients. A multi-step gene expression profiling study was conducted. First, a microarray gene expression profiling of archived paraffin-embedded tumor blocks was used to identify candidate prognostic genes (N=432). Second, a focused gene expression assay including prognostic genes was used to develop a robust clinical assay (GCPS) in stage II patients from the same cohort (N=186). Third, a predefined cut off for the GCPS was validated using an independent stage II cohort (N=216). The GCPS was validated in another set with stage II GC who underwent surgery without adjuvant treatment (N=300). GCPS was developed by summing the product of Cox regression coefficients and normalized expression levels of 8 genes (LAMP5, CDC25B, CDK1, CLIP4, LTB4R2, MATN3, NOX4, TFDP1). A prospectively defined cut-point for GCPS classified 22.7% of validation cohort treated with chemoradiotherapy (N=216) as high-risk group with 5-year recurrence rate of 58.6% compared to 85.4% in the low risk group (hazard ratio for recurrence=3.16, p=0.00004). GCPS also identified high-risk group among stage II patients treated with surgery only (hazard ratio=1.77, p=0.0053).

Complications leading reoperation after gastrectomy in patients with gastric cancer: frequency, type, and potential causes

Purpose

Reoperations after gastrectomy for gastric cancer are performed for many types of complications. Unexpected reoperations may cause mental, physical, and financial problems for patients. The aim of the present study was to evaluate the causes of reoperations and to develop a strategic decision-making process for these reoperations.

Materials and Methods

From September 2002 through August 2010, 6,131 patients underwent open conventional gastrectomy operations at Samsung Medical Center. Of these, 129 patients (2.1%) required reoperation because of postoperative complications. We performed a retrospective analysis of the patients using an electronic medical record review. Statistical data were analyzed to compare age, sex, stage, type of gastrectomy, length of operation, size of tumor, and number of lymph node metastasis between patients who had been operated and those who had not.

Results

The variables of age, sex, tumor stage, type of gastrectomy, length of operation, and number of lymph node metastases did not differ between the 2 groups. However, the mean tumor size in the reoperation group was greater than that in the non-reoperation group (5.0±3.7 [standard deviation] versus 4.1±2.9, P=0.007). The leading cause of reoperation was surgical-site infection (n=49, 0.79%). Patients with intra-abdominal bleeding were operated on again in the shortest period after the initial gastrectomy (6.3±4.2 days). Patients with incisional hernia were not reoperated on until after 208.3±81.0 days, the longest postoperative period.

Conclusions

Tumor size was the major variable leading to reoperation after gastrectomy for gastric cancer. The most common complication requiring the reoperation was a surgical site-related complication.

Exome sequencing identifies early gastric carcinoma as an early stage of advanced gastric cancer

Gastric carcinoma is one of the major causes of cancer-related mortality worldwide. Early detection and treatment leads to an excellent prognosis in patients with early gastric cancer (EGC), whereas the prognosis of patients with advanced gastric cancer (AGC) remains poor. It is unclear whether EGCs and AGCs are distinct entities or whether EGCs are the beginning stages of AGCs. We performed whole exome sequencing of four samples from patients with EGC and compared the results with those from AGCs. In both EGCs and AGCs, a total of 268 genes were commonly mutated and independent mutations were additionally found in EGCs (516 genes) and AGCs (3104 genes). A higher frequency of C>G transitions was observed in intestinal-type compared to diffuse-type carcinomas (P = 0.010). The DYRK3, GPR116, MCM10, PCDH17, PCDHB1, RDH5 and UNC5C genes are recurrently mutated in EGCs and may be involved in early carcinogenesis.

CD151 overexpression is associated with poor prognosis in patients with pT3 gastric cancer

INTRODUCTION

CD151, a transmembrane protein of the tetraspanin family, is implicated in the regulation of cell-substrate adhesion and cell migration. Overexpression of CD151 has been reported in several cancers and controls MET-dependent neoplastic growth by enhancing receptor signaling. However, association of CD151 overexpression with MET or tumor progression has not been reported in gastric cancer.

MATERIALS AND METHODS

We conducted immunohistochemical analysis of CD151 overexpression in 491 pT3 gastric carcinomas and analyzed the relationship with MET overexpression and prognostic significance.

RESULTS

CD151 was highly expressed in 119 gastric carcinomas (24.2 %) and was significantly associated with higher pN stages. Patients with CD151-positive gastric cancer showed shorter overall (p = 0.003) and disease-free survival (p = 0.001) compared with patients with CD151-negative gastric carcinoma. CD151 overexpression was an independent prognostic factor for overall survival [hazard ration (HR) 1.335; 95 % CI 1.005-1.775; p = 0.046] and disease-free survival (HR 1.903; 95 % CI 1.348-2.685; p < 0.001). Co-overexpression of CD151 and MET was observed in 30 (6.1 %) gastric cancers and was more frequent in advanced pN stages than in other groups. Moreover, co-overexpression of CD151 and MET was a strong independent prognostic factor for overall survival (HR 3.163; 95 % CI 1.958-5.108; p < 0.001) and disease-free survival (HR 3.834; 95 % CI 2.145-6.852; p < 0.001).

CONCLUSION

CD151 overexpression is an independent prognostic factor and could be a potential molecular therapeutic target in patients with advanced gastric cancers. Further studies are needed to establish the biological significance of CD151/MET co-overexpression and the potential of targeting both molecules as a therapeutic strategy.

Prognostic implication of the CpG island methylator phenotype in colorectal cancers depends on tumour location

BACKGROUND

Colorectal cancer (CRC) is usually categorised as proximal or distal CRC. Recently, many researchers have tried to determine the molecular heterogeneity of CRCs along bowel subsites. However, the differential effects of the CpG island methylator phenotype (CIMP) and microsatellite instability (MSI) on the clinical outcome according to tumour location are not well-known.

METHODS

We analysed clinicopathologic and molecular characteristics, including CIMP, MSI, KRAS and BRAF mutations, in 734 CRCs according to bowel subsites. And the prognostic value of CIMP and MSI was analysed according to tumour location.

RESULTS

We found a linear increase of female predominance, T, N category, stage, differentiation, absence of luminal necrosis, tumour -infiltrating lymphocytes, Crohn's-like lymphoid reaction, serration and mucin production from the rectum to caecum. CpG island methylator phenotype -high and MSI-high gradually increased from the rectum to caecum. CpG island methylator phenotype is a poor prognostic factor of overall survival (hazard ratio (HR): 4.13, 95% confidence interval (CI): 1.27-13.46) and disease-free survival (HR: 2.90, 95% CI: 1.04-8.08) in rectal cancers.

CONCLUSION

Clinicopathologic and molecular profiles of CRCs gradually change along bowel subsites, and the prognostic implication of CIMP is different according to tumour location.