Contrast-enhanced ultrasonography assessment of gastric cancer response to neoadjuvant chemotherapy

AIM:To quantitatively assess the ability of double contrast-enhanced ultrasound(DCUS) to detect tumor early response to pre-operative chemotherapy.METHODS:Forty-three patients with gastric cancer treated with neoadjuvant chemotherapy followed by curative resection between September 2011 and February 2012 were analyzed.Pre-operative chemotherapy regimens of fluorouracil + oxaliplatin or S-1 + oxaliplatin were administered in 2-4 cycles over 6-12 wk periods.All patients underwent contrast-enhanced computed tomography(CT) scan and DCUS before and after two courses of pre-operative chemotherapy.The therapeutic response was assessed by CT using the response evaluation criteria in solid tumors(RECIST 1.1) criteria.Tumor area was assessed by DCUS as enhanced appearance of gastric carcinoma due to tumor vascularity during the contrast phase as compared to the normal gastric wall.Histopathologic analysis was carried out according to the Mandard tumor regression grade criteria and used as the reference standard.Receiver operating characteristic(ROC) analysis was used to evaluate the efficacy of DCUS parameters in differentiating histopathological responders from non-responders.RESULTS:The study population consisted of 32 men and 11 women,with mean age of 59.7 ± 11.4 years.Neither age,sex,histologic type,tumor site,T stage,nor N stage was associated with pathological response.The responders had significantly smaller mean tumor size than the non-responders(15.7 ± 7.4 cm vs 33.3 ± 14.1 cm,P < 0.01).According to Mandard's criteria,27 patients were classified as responders,with 11(40.7%) showing decreased tumor size by DCUS.In contrast,only three(18.8%) of the 16 non-responders showed decreased tumor size by DCUS(P < 0.01).The area under the ROC curve was 0.64,with a 95%CI of 0.46-0.81.The effects of several cut-off points on diagnostic parameters were calculated in the ROC curve analysis.By maximizing Youden's index(sensitivity + specificity-1),the best cut-off point for distinguishing responders from non-responders was determined,which had optimal sensitivity of 62.9% and specificity of 56.3%.Using this cut-off point,the positive and negative predictive values of DCUS for distinguishing responders from non-responders were 70.8% and 47.4%,respectively.The overall accuracy of DCUS for therapeutic response assessment was 60.5%,slightly higher than the 53.5% for CT response assessment with RECIST criteria(P = 0.663).Although the advantage was not statistically significant,likely due to the small number of cases assessed.DCUS was able to identify decreased perfusion in responders who showed no morphological change by CT imaging,which can be occluded by such treatment effects as fibrosis and edema.CONCLUSION:DCUS may represent an innovative tool for more accurately predicting histopathological response to neoadjuvant chemotherapy before surgical resection in patients with locally-advanced gastric cancer.

Influence of up-regulation of Notch ligand DLL4 on biological behaviors of human gastric cancer cells

AIM: To investigate the potential roles of Delta-like ligand 4 (DLL4) on the biological behavior of gastric cancer cells and its molecular mechanisms. METHODS: A recombinant eukaryotic expression vector containing human DLL4 gene was constructed and transfected into the human gastric cancer cell line SGC7901. Clones with up-regulated DLL4 were selected and amplified. The effect of DLL4 up-regulation on gastric cancer cell growth was assessed using cell growth assay. The migration and invasion were assessed using a transwell migration assay and matrigel invasion assay. Matrix metalloproteinases were detected using the zymogram technique. Cells were implanted subcutaneously into male BALB/c nu/nu mice. Tumor volumes were then calculated and compared. DLL4 staining in the implanted tumor was performed using immunohistochemistry technique. RESULTS: Growth curves over a six-day time course showed significantly promoted cell proliferation of SGC7901 cells with up-regulated DLL4. DLL4 up-regulation in SGC7901 cells promoted the migration (205.4 ± 15.2 vs 22.3 ± 12.1, P < 0.05) and invasion (68.8 ± 5.3 vs 18.2 ± 6.0, P < 0.05) in vitro and tumorigenicity in vivo (2640.5 ± 923.6 mm 3 vs 1115.1 ± 223.8 mm 3 , P < 0.05). Furthermore, significantly increased mRNA level and increased secretion of matrix metalloproteinase-2 (MMP-2) proenzyme were observed in SGC7901 cells with up-regulated DLL4. However, increased MMP-9 mRNA level but decreased extracellular MMP-9 proenzyme level was observed. CONCLUSION: Our observations indicated a mechanism by which activation of DLL4-mediated Notch signaling promotes the expression and secretion of MMP-2 proenzyme and influences the progress of gastric cancer.

Transcutaneous electroacupuncture alleviates postoperative ileus after gastrectomy: A randomized clinical trial

AIM To investigate the efficacy and safety of transcutaneouselectroacupuncture(TEA) to alleviate postoperative ileus(POI) after gastrectomy.METHODS From April 2014 to February 2017, 63 gastric cancer patients were recruited from the Second Affiliated Hospital of Zhejiang University School of Medicine, Hangzhou, China. After gastrectomy, the patients were randomly allocated to the TEA(n = 33) or control(n = 30) group. The patients in the TEA group received 1 h TEA on Neiguan(ST36) and Zusanli(PC6) twice daily in the morning and afternoon until they passed flatus. The main outcomes were hours to the first flatus or bowel movement, time to nasogastric tube removal, time to liquid and semi-liquid diet, and hospital stay. The secondary outcomes included postoperative symptom assessment and complications.RESULTS Time to first flatus in the TEA group was significantly shorter than in the control group(73.19 ± 15.61 vs 82.82 ± 20.25 h, P = 0.038), especially for open gastrectomy(76.53 ± 14.29 vs 87.23 ± 20.75 h, P = 0.048). Bowel sounds on day 2 in the TEA group were significantly greater than in the control group(2.30 ± 2.61/min vs 1.05 ± 1.26/min, P = 0.017). Time to nasogastric tube removal in the TEA group was earlier than in the control group(4.22 ± 1.01 vs 4.97 ± 1.67 d, P = 0.049), as well as the time to liquid diet(5.0 ± 1.34 vs 5.83 ± 2.10 d, P = 0.039). Hospital stay in the TEA group was significantly shorter than in the control group(8.06 ± 1.75 vs 9.40 ± 3.09 d, P = 0.041). No significant differences in postoperative symptom assessment and complications were found between the groups. There were no severe adverse events related to TEA.CONCLUSION TEA accelerated bowel movements and alleviated POI after open gastrectomy and shortened hospital stay.

Retrorectal mucinous adenocarcinoma arising from a tailgut cyst:A case report and review of literature

BACKGROUND Tailgut cysts are defined as congenital cysts that develop in the rectosacral space from the residue of the primitive tail.As a congenital disease,caudal cysts are very rare,and their canceration is even rarer,which makes the disease prone to misdiagnosis and delayed treatment.We describe a case of caudal cyst with adenocarcinogenesis and summarize in detail the characteristics of cases with analytical value reported since 1990.CASE SUMMARY A 35-year-old woman found a mass in her lower abdomen 2 mo ago.She was asymptomatic at that time and was not treated because of the coronavirus disease 2019 pandemic.Two weeks ago,the patient developed abdominal distension and right waist discomfort and came to our hospital.Except for the high level of serum carcinoembryonic antigen,the medical history and laboratory tests were not remarkable.Magnetic resonance imaging showed a well-defined,slightly lobulated cystic-solid mass with a straight diameter of approximately 10 cm×9 cm in the presacral space,slightly high signal intensity on T2-weighted imaging,and moderate signal intensity on T1-weighted imaging.The mass was completely removed by laparoscopic surgery.Histopathological examination showed that the lesion was an intestinal mucinous adenocarcinoma,and the multidisciplinary team decided to implement postoperative chemotherapy.The patient recovered well,the tumor marker levels returned to normal,and tumor-free survival has been achieved thus far.CONCLUSION The case and literature summary can help clinicians and researchers develop appropriate examination and therapeutic methods for diagnosis and treatment of this rare disease.

''Sandwich'' treatment for diospyrobezoar intestinal obstruction: A case report

Intestinal obstruction is a common clinical entity encountered in surgical practice.The objective of this report is to corroborate an atypical scenario of intestinal obstruction in a Chinese patient and to focus on the diagnosis and treatment.A 27-year-old male presented with a history of gastric pain combined with nausea and abdominal distension that had been present for 5 d.The presence of a foreign body was detected by computed tomography and observed as an abnormal density within the stomach.A diospyrobezoar was revealed during gastroscopy,the extraction of which was preventeddue to its size and firmness.An endoscopic holmium laser joined with a snare was used to fragment the obstruction,which was followed by management with a conservative"sandwich"treatment strategy involving intestinal decompression with an ileus tube and Coca-Cola lavage between endoscopic lithotripsy fragmentation procedures.This strategy resulted in the successful removal of the diospyrobezoar along with multiple small bowel obstructions.The patient was discharged after abatement of symptoms.The case presented here demonstrates the implementation of a conservative,yet successful,treatment as an alternative to conventional surgical removal of intestinal obstructions.

Systematic review of laparoscopy-assisted versus open gastrectomy for advanced gastric cancer

Objective:The study compared laparoscopy-assisted gastrectomy(LAG) with open gastrectomy(OG) in the management of advanced gastric cancer(AGC).Methods:Literature search was performed in the Medline,Embase,and Cochrane Library databases to identify control studies that compared LAG and OG for AGC.A meta-analysis was conducted to examine the surgical safety and oncologic adequacy,using the random-effect model.Results:Seven eligible studies including 815 patients were analyzed.LAG was associated with less blood loss,less use of analgesics,shorter time of flatus and periods of hospital stay,but longer time of operation.The incidence of most complications was similar between the two groups.However,LAG was associated with a lower rate of pulmonary infection(odds ratio(OR) 0.19;95% confidence interval(CI) 0.05 to 0.68;P<0.05).No significant differences were noted in terms of the number of harvested lymph nodes(weighted mean difference(WMD) 1.165;95% CI-2.000 to 4.311;P>0.05),overall mortality(OR 0.65;95% CI 0.39 to 1.10;P>0.05),cancer-related mortality(OR 0.64;95% CI 0.32 to 1.25;P>0.05),or recurrence(OR 0.62;95% CI 0.33 to 1.16;P>0.05).Conclusions:LAG could be performed safely for AGC with adequate lymphadenectomy and has several short-term advantages compared with conventional OG.No differences were found in long-term outcomes.However,these results should be validated in large randomized controlled studies(RCTs) with sufficient follow-up.