Synergistic markers based on inter-covariate association estimate treatment option with lower propensity to covariates

Background

Propensity constitutes a common problem in identifying clinical outcome prediction model whose covariates include the treatment option, which is assumed to be randomly assigned but indeed dependent of other covariates in the training data. The genuine effect of treatment option cannot be elucidated under the influence of propensity. Existing approaches, such as matched-pairs study design, still cannot solve the problem for imbalanced or small datasets.

Methods

This work proposed an anti-propensity estimate of treatment option, which is generated by support vector classifier based on two synergistic markers that represent the lower and upper limits of inter-covariate association level. The algorithm for generating the synergistic markers was illustrated and the performance was evaluated on a public dataset of gene expression levels, which were obtained from surgically excised tumor samples in non-small cell lung cancer (NSCLC) patients where treatment option, i.e., adjuvant therapy or not, was known.

Results

Six covariates represented by the expression levels of ZNF217, ERCC3, PMS1, PIK3CB, BARD1, and MAPK1, were selected to generate two synergistic markers and classifier for estimating the adjuvant therapy option with substantially attenuated propensity. The estimation accuracy attained an area under the receiver-operating characteristics curve, 0.78, in the test set.

Conclusions

The proposed synergistic markers demonstrated a parsimonious and anti-propensity estimation of treatment option, which is ready for the further evaluation and application in the clinical outcome prediction model.

Analysis of a registry database for esophageal cancer from high-volume centers in China

Esophageal cancer has a high incidence among malignancies in China, but a comprehensive picture of the status of its surgical management in China has hitherto not been available. A nationwide database has recently been established to address this issue.

METHOD

A National Database was setup through a network platform, and data was collected from 70 high-volume centers (>100 esophagectomies/per year) across China. Data was entered between January 2009 and December 2014, and was analyzed in June 2015 after a minimal follow-up of 6 months for all patients. 8181 patients with complete data who received surgery for primary esophageal cancer on the Database were included in the analysis.

RESULT

In this series, there were 6052 males and 2129 females, with a mean age of 60.5 years (range: 22-90 years). The pathology in 95.5% of patients was squamous cell carcinoma. The pathological stage distribution was 1.2% in stage 0, 2.5% in Ia, 11.5% in Ib, 14.8% in IIa, 36.1% in IIb, 19.3% in IIIa, 8.3% in IIIb, 6.2% in IIIc. 1800 patients (22.0%) with locally advanced disease received preoperative neoadjuvant therapy and 3592 patients (43.9%) underwent postoperative adjuvant chemotherapy and/or radiotherapy. The esophagectomies were performed through left thoracotomy approach in 5870 cases (72.6%), through right chest approach in 2215 cases (27.4%) including right thoracotomy (21.3%) and VATS (6.1%). The 30-day postoperative mortality rate was 0.6% (43 patients), and the overall postoperative complication rate was 11.6% (951 patients). The 1-, 3-, and 5-year overall survival rates were 82.6%, 61.6%, and 52.9%, respectively.

CONCLUSION

This National Registry Database from high-volume centers provides a comprehensive picture of surgical management for esophageal cancer in China for the first time. Squamous cell carcinoma predominates, but there is heterogeneity with respect to the surgical approach and perioperative oncologic management. Overall, surgical mortality and morbidity rates are low, and good survival rates have been achieved due to improvement of surgical treatment technology in recent years.

Potential factors of specialists' willingness to write editorial and commentary: a retrospective study based on 5,091 invitations

Background

Editorials and commentaries (E/C) are common article categories and usually solicited by editors in many journals. However, not all experts accept invitation for an E/C essay for a variety of reasons. We conducted this study to explore the potential influence factors contributing whether an invitation to write E/C is accepted by a specialist.

Methods

Data of invited E/C from all journals of AME Publishing Company between January 1^st, 2018 and December 31^st, 2018 were retrospectively identified and consecutively collected. Acceptance of writing E/C from experts was recorded as "positive", while acceptance without submission, refusal, or no response, were all recorded as "negative". Factors that could potentially affect invitation acceptance were generally categorized as being related to three areas: original studies, inviting journals, and experts.

Results

A total of 5,091 invitations were sent to 4,788 experts from 79 different countries or areas to write E/C on 695 research papers from 43 journals, with a total positive acceptance rate of 18.88%. Greece (40.54%), India (36.8%), and Brazil (35.42%) were the top three countries for acceptance rate. Surgeons (surgeons 23.80% vs. non-surgeons 17.05%; P<0.001) and oncologists (oncologists 22.57% vs. non-oncologists 17.58%; P=0.029) were more likely to accept the E/C invitations. The acceptance rate decreased with the increasing number of published articles of an expert (P=0.005). The acceptance rate was the highest (28.03%) when an inviting journal was indexed in both SCIE and PubMed. ABS, VATS and JTD ranked as the top three journals with the highest invitation acceptance rate. The impact factor of journals on which original papers were published had a negative correlation with the invitation acceptance rate (P=0.015). Database-related studies had the highest acceptance rate (21.66%), while translational (16.49%) and basic studies (16.56%) had a significantly lower acceptance rate among all study types.

Conclusion

Original studies, inviting journals, and expert-related factors were all influence factors on the acceptance rate/willingness to write of E/C from invitations.

Lung cancers associated with cystic airspaces: CT features and pathologic correlation

OBJECTIVE

Lung cancer associated with cystic airspaces (LCCA) is a rare entity. The diagnosis and treatment is often delayed due to lack of comprehension of this disease. We aimed to elucidate LCCA's clinicopathological characteristics and investigate imaging features correlated with pathological invasiveness.

METHOD

The preoperative computed tomographic (CT) scans of 10,835 patients diagnosed with NSCLC between January 2015 and December 2016 were reviewed by two thoracic radiologists for association with a cystic airspace. A clinicopathological and radiological feature analysis was done.

RESULT

A total number of 123 LCCA patients were identified and four morphologic patterns were recognized: I, thin-walled type (n = 23, 18.7%); II, thick-walled type (n = 34, 27.6%); III, a cystic airspace with a mural nodule (CWN) type (n = 43, 35.0%); and IV, mixed type (n = 23, 18.7%). A solid component in the cyst wall predicted histological invasiveness in all four types of LCCA. The proportion of moderately/poorly (M/P)-differentiated subtype in type III (85.0%) was higher than in other three patterns (which were 50.0%, 50.0%, and 69.6%, respectively). Multivariate analysis revealed that type III pattern (odds ratio [OR], 6.5; 95% confidence interval [CI], 1.1-36.4; P = 0.035), part-solid/solid component in wall (part-solid: OR, 27.2; 95% CI, 5.6-3131.6; P < 0.001; solid: OR 614.6; 95% CI, 36.4-10,368.6; P < 0.001), and irregular inner surface of cyst (OR 7.0; 95% CI 1.9-26.2; P = 0.004) were independent risk factors for the M/P-differentiated subtype. EGFR mutations were the predominant genetic alterations in each type of LCCAs, but no significant difference was found among them.

CONCLUSIONS

In LCCA, morphological patterns and wall components were two important predictors for determining pathological invasiveness.

Short-term outcomes of single- versus multi-port video-assisted thoracic surgery in mediastinal diseases

OBJECTIVES

Although there is growing interest in single-port video-assisted thoracic surgery for a number of thoracic operations, there is still not enough known about its use for mediastinal pathologies. The present study was aimed at assessing the safety and efficacy of single-port video-assisted thoracic surgery in comparison with the multi-port variants in terms of short-term perioperative outcomes.

METHODS

From July 2013 to December 2015, 285 consecutive non-myasthenic adult patients undergoing single- or multi-port video-assisted thoracic surgery for mediastinal diseases including thymoma were retrospectively reviewed. Patients were stratified depending on whether the pathology was thymoma. A propensity score matching pertaining to the approach used was performed within each stratified category. Perioperative outcomes were compared between matched cohorts.

RESULTS

During the study period, 141 (49.5%) patients were treated with single-port thoracoscopic surgery. Preoperative variables were comparable between both pairs of cohorts after matching. No morbidity or mortality occurred, except 1 case of empyema in a 2-port case. Single-port technique exhibited shorter operation time (thymoma: 78.8 vs 120.0 min, P = 0.011; non-thymoma: 78.4 vs 107.9 min, P < 0.001), less intraoperative blood loss (thymoma: 42.0 vs 78.4 ml, P = 0.002; non-thymoma: 46.0 vs 62.2 ml, P = 0.001) and a lower postoperative 10-point visual analogue scale pain score (thymoma: 2.6 vs 3.3, P = 0.026; non-thymoma: 2.4 vs 3.2, P < 0.001) than multi-port techniques in both patient categories.

CONCLUSIONS

Single-port video-assisted thoracic surgery is a safe approach for patients with loco-regional mediastinal disease, with potential advantages of shorter operative time, less intraoperative bleeding and less postoperative pain when compared with multi-port techniques.

Plasma miR-940 may serve as a novel biomarker for gastric cancer

It was reported that circulating microRNAs could be applied as non-invasive biomarkers for cancer monitoring. The purpose of this study was to identify plasma miRNA that may serve as a novel biomarker for gastric cancer and to evaluate its clinical application. MicroRNA profiles were generated from plasma samples of 5 patients with gastric cancer (GC) versus 5 healthy controls (HC). MicroRNA-940 (miR-940) was one of the most downregulated miRNAs with fold change of 0.164. It was revealed that the expression of miR-940 was downregulated in both the initial set (N = 30, P < 0.0001) and the validation set (N = 80, P < 0.0001) of plasma samples of patients with gastric cancer. The sensitivity was obviously higher than the current biomarkers CEA and CA19-9 (81.25 % vs. 22.54 % and 15.71 %). MiR-940 was also significantly downregulated in gastric cancer tissue samples (N = 34, P = 0.0015), as well as in cancer cell lines (N = 7). Importantly, miR-940 was significantly highly expressed in stomach tissue samples than in other types of tissue samples including the liver, breast, thyroid, and lung. Moreover, there was a trend of lower expression of miR-940 from early to advanced stage of gastric cancer. Target prediction suggested that miR-940 regulated cell signaling including NF-κB and Wnt/β-catenin, as well as pathways of cell communication and adhesion. These pathways play critical roles in gastric cancer initiation and progression. It is the first report that miR-940 may mainly express in the stomach. Downregulation of plasma miR-940 may serve as a novel biomarker for detection of gastric cancer.

Multicenter international randomized comparison of objective and subjective outcomes between electronic and traditional chest drainage systems

BACKGROUND

The aim of this study was to assess the impact of digital versus traditional drainage devices on chest tube removal and patient satisfaction.

METHODS

A randomized trial of digital versus traditional devices after lobectomy/segmentectomy was conducted at 4 international centers (United Kingdom, Europe, Asia, United States). Patients were managed with overnight suction followed by gravity drainage. Chest tubes were removed when an air leak was not evident anymore and the drained fluid was less than 400 mL/d.

RESULTS

The groups (digital, 191 patients; traditional, 190 patients) were well matched for baseline and surgical characteristics. There were 325 lobectomies/bilobectomies and 56 segmentectomies, 308 of which were performed by video-assisted thoracic surgery (VATS). Patients randomized to digital systems had a significantly shorter air leak duration (1.0 versus 2.2 days; p=0.001), duration of chest tube placement (3.6 versus 4.7 days; p=0.0001), and postoperative length of stay (4.6 versus 5.6 days; p<0.0001). Subjective end points revealed a perceived improved ability to arise from bed (p=0.008), system convenience for patients and personnel (p=0.02), and the potential for being comfortable when discharged home with the device (p=0.06). A mean difference of 2.6 days from air leak cessation to tube removal was observed, which was similar in the 2 groups (p=0.7). Multivariable regression analysis showed that duration of chest tube placement after air leak cessation was directly associated with the amount of fluid drained during the first 48 hours (p=0.01) and the duration of air leak (p=0.008), independent of hospital location.

CONCLUSIONS

Patients managed with digital drainage systems experienced a shorter duration of chest tube placement, shorter hospital stays, and higher satisfaction scores compared with those managed with traditional devices. (

CLINICAL TRIAL REGISTRATION NUMBER

NCT01747889.).

Lack of correlation between vacuolating cytotoxin activity, cagA gene in Helicobacter pylori, and peptic ulcer disease in children

To determine the prevalence of the cagA gene and vacuolating cytotoxin in Helicobacter pylori isolates obtained from children and to characterize the relationship between cagA, cytotoxin production, and ulcerogenesis, pediatric Helicobacter pylori isolates were tested for cagA by the polymerase chain reaction and for vacuolating cytotoxin by a cell culture assay. Helicobacter pylori isolates were obtained from 33 children referred for upper gastrointestinal endoscopy. Twenty-six of these isolates were tested for cagA by the polymerase chain reaction; all 26 (100%) were positive. Of the 26 children from whom these isolates were obtained, 26 (100%) had chronic gastritis and 12 (46%) had duodenal ulcers. Nine (30%) of 30 isolates tested showed expression of vacuolating cytotoxin, only three of which came from patients with duodenal ulceration (odds ratio 0.81, 95% confidence interval 0.1-5.3). Of the 23 cagA-positive isolates tested for cytotoxin, only nine (39%) were positive. There was no association between vacuolating cytotoxin and clinical symptoms, nor was cytotoxicity associated with ulcerogenesis. In summary, the findings suggest that cagA is not a marker of duodenal ulceration or of vacuolating cytotoxin production in children referred for endoscopy.