Deep Learning-Based Survival Analysis Identified Associations Between Molecular Subtype and Optimal Adjuvant Treatment of Patients With Gastric Cancer.

PURPOSE: Gastric cancer (GC) is the third-leading cause of cancer-related deaths. Several pivotal clinical trials of adjuvant treatments were performed during the previous decade; however, the optimal regimen for adjuvant treatment of GC remains controversial. PATIENTS AND METHODS: We developed a novel deep learning-based survival model (survival recurrent network [SRN]) in patients with GC by including all available clinical and pathologic data and treatment regimens. This model uses time-sequential data only in the training step, and upon being trained, it receives the initial data from the first visit and then sequentially predicts the outcome at each time point until it reaches 5 years. In total, 1,190 patients from three cohorts (the Asian Cancer Research Group cohort, n = 300; the fluorouracil, leucovorin, and radiotherapy cohort, n = 432; and the Adjuvant Chemoradiation Therapy in Stomach Cancer cohort, n = 458) were included in the analysis. In addition, we added Asian Cancer Research Group molecular classifications into the prediction model. SRN simulated the sequential learning process of clinicians in the outpatient clinic using a recurrent neural network and time-sequential outcome data. RESULTS: The mean area under the receiver operating characteristics curve was 0.92 ± 0.049 at the fifth year. The SRN demonstrated that GC with a mesenchymal subtype should elicit a more risk-adapted postoperative treatment strategy as a result of its high recurrence rate. In addition, the SRN found that GCs with microsatellite instability and GCs of the papillary type exhibited significantly more favorable survival outcomes after capecitabine plus cisplatin chemotherapy alone. CONCLUSION: Our SRN predicted survival at a high rate, reaching 92% at postoperative year 5. Our findings suggest that SRN-based clinical trials or risk-adapted adjuvant trials could be considered for patients with GC to investigate more individualized adjuvant treatments after curative gastrectomy.

Effect of DA-9701 on Gastric Motor Function Assessed by Magnetic Resonance Imaging in Healthy Volunteers: A Randomized, Double-Blind, Placebo-Controlled Trial.

BACKGROUND: Improving gastric accommodation and gastric emptying is an attractive physiological treatment target in patients with functional dyspepsia (FD). We evaluated the effect of DA-9701, a new drug for FD, on gastric motor function after a meal in healthy volunteers using magnetic resonance imaging (MRI). METHODS: Forty healthy volunteers were randomly allocated to receive either DA-9701 or placebo. After 5 days of treatment, subjects underwent gastric MRI (60 min before and 15, 30, 45, 60, 90, and 120 min after a liquid test meal). Gastric volume was measured through 3-dimensional reconstruction from MRI data. We analyzed 4 outcome variables including changes in total gastric volume (TGV), proximal TGV, and proximal to distal TGV ratio after a meal and gastric emptying rates after adjusting values at the pre-test meal. RESULTS: Changes in TGV and proximal TGV after a meal did not differ between the DA-9701 and placebo groups (difference between groups -25.9 mL, 95% confidence interval [CI] -54.0 to 2.3 mL, P = 0.070 and -2.9 mL, 95% CI -30.3 to 24.5 mL, P = 0.832, respectively). However, pre-treatment with DA-9701 increased postprandial proximal to distal TGV ratio more than placebo (difference between groups 0.93, 95% CI 0.08 to 1.79, P = 0.034). In addition, pre-treatment with DA-9701 significantly increased gastric emptying as compared with placebo (mean difference between groups 3.41%, 95% CI 0.54% to 6.29%, P = 0.021, by mixed model for repeated measures). CONCLUSION: Our results suggested that DA-9701 enhances gastric emptying and does not significantly affect gastric accommodation in healthy volunteers. Further studies to confirm whether DA-9701 enhances these gastric motor functions in patients with FD are warranted. TRIAL REGISTRATION: ClinicalTrials.gov NCT02091635.

Effect of DA-9701 on colorectal distension-induced visceral hypersensitivity in a rat model.

BACKGROUND/AIMS: DA-9701 is a newly developed drug made from the vegetal extracts of Pharbitidis semen and Co-rydalis tuber. The aim of this study was to evaluate the effect of DA-9701 on colorectal distension (CRD)-induced visceral hypersensitivity in a rat model. METHODS: Male Sprague-Dawley rats were subjected to neonatal colon irritation (CI) using CRD at 1 week after birth (CI group). At 6 weeks after birth, CRD was applied to these rats with a pressure of 20 to 90 mm Hg, and changes in the mean arterial pressure (MAP) were measured at baseline (i.e., without any drug administration) and after the administration of different doses of DA-9701. RESULTS: In the absence of DA-9701, the MAP changes after CRD were significantly higher in the CI group than in the control group at all applied pressures. In the control group, MAP changes after CRD were not significantly affected by the administration of DA-9701. In the CI group, however, the administration of DA-9701 resulted in a significant decrease in MAP changes after CRD. The administration of DA-9701 at a dose of 1.0 mg/kg produced a more significant decrease in MAP changes than the 0.3 mg/kg dose. CONCLUSIONS: The administration of DA-9701 resulted in a significant increase in pain threshold in rats with CRD-induced visceral hypersensitivity.

Effects of DA-9701, a novel prokinetic agent, on gastric accommodation in conscious dogs.

BACKGROUND AND AIM: DA-9701, a novel prokinetic agent formulated with Pharbitis Semen and Corydalis Tuber, has strong prokinetic effects, and enhances gastric compliance in conscious dogs. In this study, the effects of DA-9701 on gastric accommodation were studied in conscious dogs. METHODS: Beagle dogs with an implanted gastric cannula in the stomach were used in this study. After an overnight fast, the dogs received DA-9701 orally, or served as a positive control that received sumatriptan or a negative control before ingestion of a meal. The basal and postprandial gastric volumes were monitored at a constant operating pressure using an electronic barostat. To investigate the long-lasting effects on increased postprandial gastric volume, the area under the volume versus time curve (AUC) was calculated. RESULTS: DA-9701 significantly increased the basal gastric volume compared to the negative controls (P < 0.05); the effects were comparable to sumatriptan. DA-9701 and sumatriptan significantly increased gastric accommodation compared to the negative control (P < 0.05). In the negative control, the gastric volume reached the maximal volume 40 min after the meal, and then gradually decreased. However, with DA-9701, the increased gastric volume remained significantly elevated for 60 min postprandially (P < 0.05). DA-9701 significantly increased the value of AUC compared to the negative control; this was observed during both the early and late postprandial phases (P < 0.05). CONCLUSIONS: A novel prokinetic agent, DA-9701, improved gastric accommodation by increasing the postprandial gastric volume; these effects persisted for 60 min after a meal.

The CpG island methylator phenotype may confer a survival benefit in patients with stage II or III colorectal carcinomas receiving fluoropyrimidine-based adjuvant chemotherapy.

BACKGROUND: Colorectal carcinoma (CRC) with CpG island methylator phenotype (CIMP) is recognized as a distinct subgroup of CRC, and CIMP status affects prognosis and response to chemotherapy. Identification of CIMP status in CRC is important for proper patient management. In Eastern countries, however, the clinicopathologic and molecular characteristics and prognosis of CRCs with CIMP are still unclear. METHODS: A total of 245 patients who underwent their first surgical resection for sporadic CRC were enrolled and CIMP status of the CRCs was determined using the quantitative MethyLight assay. The clinicopathologic and molecular characteristics were reviewed and compared according to CIMP status. In addition, the three-year recurrence-free survival (RFS) of 124 patients with stage II or stage III CRC was analyzed in order to assess the effectiveness of fluoropyrimidine-based adjuvant chemotherapy with respect to CIMP status. RESULTS: CIMP-high CRCs were identified in 34 cases (13.9%), and were significantly associated with proximal tumor location, poorly differentiated carcinoma, mucinous histology, and high frequencies of BRAF mutation, MGMT methylation, and MSI-high compared to CIMP-low/negative carcinomas. For patients with stage II or III CIMP-low/negative CRCs, no significant difference was found in RFS between those undergoing surgery alone and those receiving surgery with fluoropyrimidine-based adjuvant chemotherapy. However, for patients with CIMP-high CRCs, patients undergoing surgery with fluoropyrimidine-based adjuvant chemotherapy (n = 17; three-year RFS: 100%) showed significantly better RFS than patients treated with surgery alone (n = 7; three-year RFS: 71.4%) (P = 0.022). CONCLUSIONS: Our results suggest that selected patients with CIMP-high CRC may benefit from fluoropyrimidine-based adjuvant chemotherapy with longer RFS. Further large scale-studies are required to confirm our results.

Idiopathic proximal hemimegacolon: radiologic findings and analyses of clinical and physiological characteristics.

BACKGROUND: Idiopathic megacolon with bowel dilatation only proximal to the splenic flexure is an uncommon and poorly characterized disease. This study aimed to identify the characteristics of idiopathic proximal hemimegacolon. METHODS: Five patients (2 males and 3 females) were diagnosed to have idiopathic proximal hemimegacolon and their radiologic, clinical, and physiological characteristics were reviewed. Hirschsprung's disease and other known causes of bowel dilatation were excluded by the presence of rectoanal inhibitory reflex and reviewing medical records. RESULTS: Mean age at diagnosis and symptom onset were 50.4 years and 47.2 years, respectively. Four patients presented with constipation, and all five patients showed abdominal distention and abdominal pain. Four patients were successfully treated and maintained only with laxatives and prokinetics without enema. Only one patient underwent surgery for intractable constipation. Mean maximal diameters of each segment of colons measured by computed tomography were 57.5 mm, 69.3 mm, 73.0 mm, 33.3 mm, 24.0 mm, and 27.3 mm for cecum, ascending colon, transverse colon, descending colon, sigmoid colon, and rectum, respectively. Colon transit time was delayed in four patients with mean value of 90.0 h. CONCLUSIONS: These results indicated that patients with idiopathic proximal hemimegacolon may be treated successfully only with medical therapy in most cases.