bluuebunny/crossref_metadata_2025_split huggingface dataset:
Time-average velocity estimation through surface-wave analysis: Part 2 — P-wave velocity
Authors: Valentina Socco Laura , Comina Cesare 
Published: March 2017

Surface waves (SWs) in seismic records can be used to extract local dispersion curves (DCs) along a seismic line. These curves can be used to estimate near-surface S-wave velocity models. If the velocity models are used to compute S-wave static corrections, the required information consists of S-wave time-average velocities that define the one-way time for a given datum plan depth. However, given the wider use of P-wave reflection seismic with respect to S-wave surveys, the estimate of P-wave time-average velocity would be more useful. We therefore focus on the possibility of also extracting time-average P-wave velocity models from SW dispersion data. We start from a known 1D S-wave velocity model along the line, with its relevant DC, and we estimate a wavelength/depth relationship for SWs. We found that this relationship is sensitive to Poisson’s ratio, and we develop a simple method for estimating an “apparent” Poisson’s ratio profile, defined as the Poisson’s ratio value that relates the time-average S-wave velocity to the time-average P-wave velocity. Hence, we transform the time-average S-wave velocity models estimated from the DCs into the time-average P-wave velocity models along the seismic line. We tested the method on synthetic and field data and found that it is possible to retrieve time-average P-wave velocity models with uncertainties mostly less than 10% in laterally varying sites and one-way traveltime for P-waves with less than 5 ms uncertainty with respect to P-wave tomography data. To our knowledge, this is the first method for reliable estimation of P-wave velocity from SW data without any a priori information or additional data.
Patients of Asian descent with gastric cancer treated in the United States: Comparative characteristics and survival outcomes.
Authors: Rhome Ryan , Moshier Erin , Buckstein Michael 
Published: March 2017

10 Background: Asian gastric cancer trials often show better outcomes than similar Western trials suggesting a possible difference in disease characteristics or biology. Large databases can be used to assess whether ethnic differences persist in the United States. Methods: The National Cancer Database was queried to examine disease characteristics, treatment utilization, and outcomes for gastric cancer from 2004-2013 for Asian vs. non-Asian patients. Patients were excluded with inadequate follow-up, unknown staging or race. Cox proportional hazards model was used to assess hazard ratio (HR) of death. Results: 101,426 patients were analyzed (6,994 Asians, 94,432 non-Asians). Asian patients were more likely to be female, younger, treated at academic centers, early stage, lower co-morbidity score, and high grade vs. non-Asian (Chi-square, all p<0.001). Asian patients were less likely to receive chemotherapy or radiation or have a positive margin. HRs of death (adjusted for age, sex, facility, histology, insurance, co-morbidity score, margin, grade, surgery, radiation, and chemotherapy) for Asian patients are shown in the table. Further dividing by most represented Asian sub-groups showed differences between countries of origin. Conclusions: Imbalances exist in clinical features and treatment utilization in Asian patients compared to non-Asians. After adjustment, Asian race is associated with higher overall survival. Adjusted sub-group analyses show survival differences by country of origin, suggesting biological variability. [Table: see text]
Post-gastrectomy nutrition risk index can be a good predictive factor for survival.
Authors: Fujiya Keiichi , Kawamura Taiichi , Omae Katsuhiro , Nishiwaki Noriyuki , Kaji Sanae , Hikage Makoto , Makuuchi Rie , Tokunaga Masanori , Tanizawa Yutaka , Bando Etsuro , Terashima Masanori 
Published: March 2017

101 Background: Preoperative malnutrition worsens morbidity and survival, however the role of post-gastrectomy nutritional status in survival remains unclear. The nutrition risk index (NRI) described by Buzby is a scoring system for identifying patients with preoperative poor nutrition status. However, the significance of NRI in evaluating post-gastrectomy nutritional status has not yet been established. Therefore, we aimed to clarify whether malnutrition condition evaluated by NRI after surgery can be a predictive factor for long-term survival in patients with gastric cancer. Methods: Pathological stage I, II, and III gastric cancer patients who underwent curative gastrectomy between 2002 and 2013 were included in this study. NRI was calculated using the following formula; (1.489 × serum albumin, g/L) + (41.7 × current weight/usual weight), and we defined an NRI of above 97.5 as normal nutrition (N group) and 97.5 or below as malnutrition (M group). NRI was evaluated before gastrectomy and 1, 3 and 12 months after gastrectomy. The correlations of clinicopathological characteristics, surgical treatment and overall survival, with nutritional status were retrospectively evaluated. Results: A total of 2552 patients were enrolled. There were significant differences in age, sex, body mass index, performance status, co-morbidity, histology and malignant stage between the groups before gastrectomy. Overall survival in the M group was significantly poorer, both before gastrectomy (adjusted HR 1.31; p < 0.001) and at 1 month (adjusted HR 1.52; p < 0.001), 3 months (adjusted HR 1.35; p = 0.004) and 12 months (adjusted HR 1.37; p = 0.006) after gastrectomy. In multivariate analysis, low NRI at 12 months after gastrectomy, age, co-morbidity and malignant stage were independently associated with overall survival. Overall survival in patients who fulfilled preoperative normal nutrition status criteria was also significantly poorer at 12 months after gastrectomy in the M group. Conclusions: Malnutrition after surgery, as well as before surgery, had a significant impact on overall survival. Postoperative nutritional statue evaluated by NRI may be a good predictive marker for long-term survival.
Pathologic nodal response in gastric cancer: Do all patients need adjuvant therapy?
Authors: Smaglo Brandon George , Sada Yvonne , Tran Cao Hop Sanderson , Akce Mehmet , Mok Henry , Musher Benjamin Leon , Massarweh Nader Nabile 
Published: March 2017

107 Background: Recent data from the MAGIC trial show that pathologically positive lymph nodes (ypN+) despite neoadjuvant (NA) chemotherapy are associated with poorer survival. Although the use of NA therapy has increased, pathologic disease response to multimodality therapy (MMT) and its impact on outcome have not been well-defined. Methods: This retrospective cohort study of the National Cancer Database included patients with cN+ gastric cancer who underwent NA therapy followed by surgical resection between 2006 and 2012. Patients were categorized by NA treatment (chemotherapy or concurrent chemoradiation). Pre-treatment clinical (cN) and pathologic nodal staging (ypN) were used to determine downstaging rates from cN+ to ypN0. The association between overall risk of death and NA treatment, nodal response, and the use of adjuvant therapy was evaluated with multivariable Cox regression. Results: Among 1,489 patients with cN+ gastric cancer receiving NA therapy, 45.5% were treated with chemotherapy and 54.5% with chemoradiation. Rates of nodal downstaging were 29.9% for chemotherapy and 45.4% for chemoradiation. On multivariable analysis, treatment sequence and type were not associated with risk of death. Median survival was significantly lower in patients with ypN+ compared to those with ypN0 disease (27.7 vs 79.7 months; log-rank, p < 0.001).Among patients with ypN+ disease (n = 918), median survival was greater if adjuvant therapy was received (32.6 months vs. 25.3 months, log-rank, p < 0.001); adjuvant therapy was associated with a 19% decreased risk of death (Hazard Ratio [HR] 0.81; 95% CI 0.66-0.99), with further reduction among those who underwent a margin negative resection (HR 0.73; 95% CI 0.58-0.92). In patients with ypN0, adjuvant therapy was not associated with a lower risk of death. Conclusions: Over one third of node-positive gastric cancers demonstrated pathologic nodal downstaging with NA treatment, with chemoradiation yielding a higher response than chemotherapy. Patients with ypN+ had worse survival, and appeared to benefit from adjuvant therapy. Future gastric cancer trials should better define the role for NA chemoradiation and help individualize the use of adjuvant therapy based on nodal response.
Impact of current “insufficient” clinical nodal staging on treatment decisions and response to neoadjuvant chemoradiotherapy in esophageal cancer patients.
Authors: Dijksterhuis Willemieke P.M. , Hulshoff Jan-Binne , van Dullemen Hendrik M. , Kats-Ugurlu Gursah , Burgerhof Johannes G.M. , Korteweg Tijmen , Mul Veronique E.M. , Hospers Geke , Plukker John Theodorus 
Published: March 2017

111 Background: Although essential in treatment decision making, clinical nodal (cN) staging in esophageal cancer (EC) remains difficult. We assessed the rate of nodal up- and downstaging and its prognostic value on 5-year disease-free survival (DFS) in EC patients treated with surgery-alone or with neoadjuvant chemoradiotherapy (nCRT). Methods: For this retrospective study, we included 395 EC patients who underwent a curative esophagectomy with or without nCRT between 2000 and 2015. The surgery-alone and nCRT group were matched on clinical T-stage (cT), cN-stage, and histopathological type using propensity score matching ( n=270). Staging consisted of PET with CT, or PET/CT, and endoscopic ultrasonography (n = 235). We compared cN and pathological N-stage (pN) and scored correct, down- and upstaging. The prognostic value of nodal up- and downstaging and localization of node metastases on 5-year DFS were assessed with multivariate Cox regression analysis (factors with a P-value <0.1 on univariate analysis). Results: Nodal upstaging (43.0% vs. 16.3%), correct staging (31.9% vs. 28.1%) and downstaging (25.2% vs. 55.6%) differed between the surgery-alone and nCRT group ( P<0.001). Nodal upstaging was commonly present in adenocarcinoma and cT3-4a tumors. Independent prognostic factors for DFS were pN ( P=0.002) and lymph-angioinvasion ( P=0.016) in the surgery and cN metastasis under the diaphragm ( P=0.012) and lymph node ratio ( P=0.034) in the nCRT group. Conclusions: In esophageal cancer, clinical lymph node staging is still insufficient with >25% nodal downstaging. This inaccuracy might impede assessment of true nodal response to nCRT, affording dubious decisions for a ‘wait-and-see’ strategy.
Phase II trial of adjuvant immunotherapy with autologous tumor-derived Gp96 vaccination in patients with gastric cancer.
Authors: Chen Lin , Zhang Kecheng , Peng Zheng , Wei Bo , Xi Hongqing , Wang Xinxin , Wang Ning , Cui Jianxin 
Published: March 2017

117 Background: Autologous, tumor-derived heat shock protein Gp96 peptides complexes have shown antitumor potential in various cancers. We conducted the first Phase II trial to evaluate the safety and efficacy of Gp96 vaccination in adjuvant settings for patients with gastric cancer. Methods: Consecutive patients from November 2012 to December 2015 were enrolled. Participants were allocated to the experimental group or control group, receiving Gp96 vaccination plus chemotherapy or chemotherapy alone respectively. The primary endpoints were disease-free survival and toxicity. The secondary outcomes were overall survival and tumor-specific immune responses. Results: Thirty-nine and forty patients received Gp96 vaccination plus chemotherapy and chemotherapy alone in the adjuvant settings respectively. Significant increased tumor-specific immune responses were observed after Gp96 vaccination. There were comparable disease-free survival ( p = 0.413; HR: 0.75; 95% CI: 0.37−1.48) and overall survival ( p = 0.485; HR: 0.68; 95% CI: 0.24−1.96) between experimental group and control group. In subgroup of patients with stage II and stage III gastric cancer, patients who have received Gp96 vaccination had improved disease-free survival compared those who have not ( p = 0.044; HR: 0.45; 95% CI: 0.22−0.96). Gp96 vaccination plus chemotherapy was well tolerated and no Gp96-related serious adverse event has been observed. Conclusions: Gp96 vaccination could elicit tumor-specific immune responses and could be safely used in adjuvant settings combined with chemotherapy. Patients with less aggressive diseases might benefit from Gp96 therapy.
Gastrointestinal stromal tumors: Immune protein expression and clinical outcomes.
Authors: Blakely Andrew M. , Matoso Andres , Miner Thomas J. 
Published: March 2017

124 Background: The immune microenvironment is emerging as an important prognostic factor with potential therapeutic targets for various malignancies. Although programmed death-ligand 1 (PD-L1) and indoleamine 2,3-dioxygenase (IDO) have been studied in some tumor types, significance of their expression in gastrointestinal stromal tumors (GISTs) is largely unknown. Methods: Tissue microarrays at an academic tertiary care center were constructed from pathology files from 1996 to 2016. Immunohistochemistry for PD-L1 and IDO was performed and correlated with tumor size, mitoses, and clinical outcomes. Tumor infiltrating lymphocytes (TILs) were counted using image analysis software. Results: 131 GISTs were analyzed. Median patient age was 64 years (range 30-89); 51.1% were male. Tumor location included 89 stomach (67.9%), 34 small bowel (26.0%), 4 colorectal (3.1%), and 4 other (3.1%). Median follow-up was 58 months. Mean tumor size was 5.6±4.5cm, range 0.5 to 24; mean mitoses were 7.2/50HPF. 19 (14.5%) metastasized to mesentery (n = 8), liver (n = 6), and elsewhere (n = 5). Mean survival was 61 months (range 7-127); 5 patients died of disease (3.8%). PD-L1 immunostain was positive in 89 (67.9%), including 11 of 19 (57.9%) malignant and 78 of 112 (69.6%) benign tumors (p = 0.4). PD-L1 positive tumors were larger (6.3±4.4 vs. 4.4±3.4 cm; p = 0.02) and had more mitoses/50HPF (8.9±5.4 vs. 3.9±3.5; p = 0.006) than PD-L1 negative tumors. IDO immunostain was positive in 116 (88.5%), including 14 of 19 (73.7%) malignant and 102 of 112 (91.1%) benign tumors (p = 0.07). There was no significant difference in size or mitotic count between IDO positive and negative tumors. Mean number of CD8-positive TILs was 168±35/mm2 and mean number of PD-L1 positive TILs was 147±28/mm2 in PD-L1 positive tumors. PD-L1 positive tumors had significantly more TILs than PD-L1 negative tumors (113±21 vs. 104±18; p < 0.001). Conclusions: The majority of GISTs express PD-L1 and IDO. Expression of PD-L1 was associated with increased tumor size and higher mitotic activity. PD-L1 and IDO could play a significant role in the tumor biology of GISTs; immunotherapy targeting one or both may provide novel treatment options.
Attenuation of the volume-outcome relationship for gastrointestinal cancer surgery over time: Is a push towards continued regionalization justified?
Authors: Wasif Nabil , Chang Yu-Hui , Mathur Amit , Pockaj Barbara A. , Gray Richard J. , Etzioni David 
Published: March 2017

131 Background: Research demonstrating a volume-outcome relationship has resulted in regionalization of complex cancer surgery to high volume hospitals. A simultaneous national trend towards improved surgical outcomes brings into question whether the potential benefits of regionalization are still relevant. We hypothesize that the difference in adjusted post-operative mortality between low and high volume hospitals has decreased over time. Methods: The National Cancer Database (NCDB) was used to identify patients with colon, esophageal, and pancreatic cancer undergoing curative intent surgery from 2003-2011. Hospitals were divided into low ( < 25th percentile), medium (25th-75th) and high ( > 75thpercentile) volume groups depending on annual volume of cancer-specific surgery. Year-specific hospital averaged observed/expected (O/E) ratios were calculated for 90-day mortality. Poisson regression was used to model hospital averaged O/E ratios over time. Results: Our study population included 343,929 patients with colon (88%), esophageal (5%) and pancreatic (7%) cancer. There were significant (p < 0.05) improvements in adjusted 90-day mortality from 2003 and 2011 for all volume categories and cancer types, except in high volume hospitals for esophageal cancer. In 2003, high volume hospitals had significantly better outcomes compared to low volume hospitals for all cancer types, as suggested by lower O/E ratios for 90 day mortality (p < 0.05). However, by 2011 the difference in O/E ratios for 90 day mortality was no longer significantly lower for high compared to low volume hospitals (p > 0.05); this was true for all three cancer types (Figure1). Conclusions: During the period of our study, 90-day mortality following gastrointestinal cancer surgery improved in low, medium and high volume hospitals. However, by 2011 the difference in adjusted post-operative mortality between low and high volume hospitals was not significantly different, likely due to global improvements in operative and peri-operative care. This attenuation of the volume-outcome curve has important implications for policy pertaining to regionalization of cancer care in the US.
Quality of life (QOL) in esophageal cancer patients treated with tri-modality therapy: Is the CROSS protocol better?
Authors: Woo Rachel , Chan Edwin , Vanderwater Catherine , Cho Charles , Wong Jason , Xu Wei , Zhang Qihuang , Liu Geoffrey , Zhang Beibei , Cheung Agnes , Lee Alex , Chacko Pravin Philip , Fadhel Ehab , Kassam Zahra 
Published: March 2017

132 Background: To investigate the impact of trimodality therapy on QOL in esophageal cancer patients and compare the CROSS regimen to neoadjuvant cisplatin/5FU. Methods: In a non-randomized, prospective cohort study, patients undergoing neoadjuvant chemoradiation (CRT) and esophagectomy between June 2012 and Nov 2015, with esophageal adenocarcinoma or squamous cell cancer, T1-4N0-3 (AJCC 7thEd.), completed the EORTC-QLQ-C30 at baseline, end of RT, 6 months, and then annually. A 10-point difference in QOL scores was considered clinically significant. Results: Of 35 patients, 13 received cisplatin/5FU concurrent with 45-50 Gy/25fr; 22 received carboplatin/paclitaxel with 41.4 Gy/23fr (CROSS). Median follow up was 16 months (range 2-49). Questionnaire compliance ranged from 75-100%. Median differences (MD) for physical, role, cognitive, social, & global function, and fatigue, nausea/vomiting (N/V), pain, appetite, & constipation were clinically worse at the end of RT. Statistical worsening was found at the end of RT for global (MD -17, p = 0.001), physical (-17, p = 0.001), role (-33, p = 0.001), & social function (-17, p = 0.003), and for fatigue (28, p = 0.001), N/V (17, p = 0.003), pain (17, p = 0.01), dyspnea (0, p = 0.015), sleep disorder (0, p = 0.049) & appetite (33.3, p = 0.001). Clinical worsening persisted on several domains at 6 months. All scores at 1 year improved at least to baseline, except role functioning (-17, p = 1.0) and appetite (33, p = 0.5) which were clinically, but not statistically worse. No significant difference in QOL was found between cisplatin/5FU and CROSS groups at baseline or end of RT. At 6 months median scores were statistically significantly better for pain, fatigue, role, social, and global functioning in the CROSS group. Global QOL at 1 year remained significantly better in the CROSS group. Higher baseline global QOL was associated with improved OS (p = 0.04) and DFS (p = 0.02). Conclusions: QOL worsened across several domains until 6 months post-RT. Most scores returned to baseline or improved at 1 year except for role functioning and appetite. A larger cohort or controlled trial is needed to confirm our findings of a better long term QOL with the CROSS regimen.
Prospective randomized crossover study of effects of traditional Japanese herbal medicine rikkunshito on food intake and plasma acylated ghrelin levels in patients with esophageal cancer administered with cisplatin-based chemotherapy.
Authors: Hamai Yoichi , Yoshiya Tomoharu , Emi Manabu , Furukawa Takaoki , Ibuki Yuta , Okada Morihito 
Published: March 2017

133 Background: Cisplatin (CDDP) is an important chemotherapeutic drug for treating esophageal cancer that often induces chemotherapy-induced nausea and vomiting (CINV). Acylated ghrelin (AG) is an orexigenic gut hormone that can alleviate CINV. We evaluated whether rikkunshito (RKT), a traditional Japanese herbal medicine with an orexigenic effect, can improve CINV-induced anorexia and increase levels of plasma AG in patients with esophageal cancer administered with CDDP-based chemotherapy. Methods: This prospective randomized crossover study included 20 patients with esophageal cancer who were administered with CDDP-based chemotherapy between July 2013 and March 2016. Tenof them were assigned to group A (1st course with 7.5 g/day RKT on days 1 - 14; 2nd course without RKT [control]) and 10 were assigned to group B (1st course without RKT [control]; 2nd course with RKT). Food intake and levels of plasma AG (fmol/mL) were compared between the control and RKT courses. Results: Data from 18 of the patients were included in this analysis, as chemotherapy was immediately stopped due to deteriorating renal function in one patients and intracerebral bleeding in another. The median rate at which food intake decreased between days 4 and 6, which is associated with delayed-onset CINV, was considerably lower in the groups given RKT than in the control (2% vs. 30%; p = 0.07). Median levels of AG significantly decreased between days 1 to 3 in the group given RKT (15.1 to 9.6 fmol/mL, p = 0.001) and the control (14.1 to 10.2, p = 0.003), and then obviously increased from days 3 to 8 in patients with both courses (RKT: 9.6 to 15.7 fmol/mL, p < 0.0001; control: 10.2 to 17.8, p = 0.0002). However, the rate at which median plasm AG levels increased from days 3 to 8 tend to be higher in the RKT, than in the control group (68% vs. 48%, p = 0.08). Conclusions: RKT might improve delayed-onset CINV as well as CINV-induced anorexia and increases in plasma AG levels among patients with esophageal cancer who undergo highly emetogenic CDDP-based chemotherapy. Clinical trial information: UMIN000010747.