Gastrointestinal stromal tumor (GIST) is a group of tumors which is independently derived from the mesenchymal stem cells of the digestive tract,and consists of undifferentiated or multi-functional spindle or epithelioid cells.Most of the rectal stromal tumor located at the middle or lower part of the rectum,and presented with exogenous growth outside of the rectum cavity.Rectal stromal tumor accounted for 5％ of GIST.Rectal stromal tumor is easily missed or misdiagnosed because of insidious onset and non-typical clinical manifestations.The diagnosis of rectal stromal tumor relies on immunohistochemical staining (CD117 and CD34) and pathological examination.Surgical resection is the first choice for the treatment of local primary rectal stromal tumor.Protection of the integrity of the tumor is important during operation,and routine lymph node dissection is not recommended.Molecular targeted drug mesylate imatinib is adopted in the pre-and postoperative adjuvant therapy.However,due to the rarity of rectal stromal tumor,the treatment strategies need further investigation.

Objective To identify if intraoperative injecting carbon nanoparticles (CNP) is a feasible,precise and safe method of sentinel lymph node mapping (SLNM).Methods In this study,63 colon cancer patients from July 2009 to March 2011 were included.1 ml (50 mg) CNP was locally injected into subserosa around the neoplasm intraoperatively.In comparison 90 colon cancer patients underwent radical resection without CNP injection (control group).After operation both SLN and non-SLN were collected and analyzed compared with the lymphnodes collected in control group.Clinical feasibility,detection rate,and sensitivity of the method were analyzed.The categorical variables were analyzed with the Pearson Chi-square or Fisher's exact test,whereas the continuous variables were analyzed with t test,significance was determined as P ＜ 0.05.Results 1640 lymph nodes were detected in 63 patients(with an average 26.0 per case),SLNs were identified in all cases(100％),481 SLNs were collected (with an average 7.6).Totally 198 metastatic lymph nodes were detected in 31 patients (average 3.1),including 34 metastatic SLNs.Total number of lymph nodes and number of metastatic lymph nodes detected in CNP group were higher than those of control group (P =0.000,P =0.001).The sensitivity,accuracy,specificity and false negative rate were 52％,76％,100％ and 48％ respectively.The sensitivity,accuracy,specificity and false negative rate were adjusted to 79％,90％,100％ and 21％ respectively if all T4 stage patients were excluded.Conclusions SLN detection can increase the number of lymph nodes harvested and improve the detection rate of lymph node metastasis.

Objective To investigate the number, distribution and metastatic rule of lymph nodes in the mesorectum of rectal cancer specimen after processing the recta] cancer specimen with modified fat clearance technique. Methods Sixty patients with mid-low rectal cancer who had been admitted to Peking University School of Ontology from 2003 to 2008 were assigned to test group. All the 60 patients who denied neo-adjuvant therapy were treated with total mesorectal excision, and the rectums resected were processed with the modified fat clearance technique. Rectums from another 50 patients with mid-low rectal cancer in control group were fixed in formalin solution for 24 hours. The mesorectum was divided into anterior, posterior, left and right quadrants, and each quadrant was further divided into upper, middle and lower parts. The numbers of lymph nodes harvested and metastatic rate of lymph nodes between the 2 groups were analyzed by t test and chi-square test. Results (1) The numbers of lymph nodes harvested in the test and control groups were 1436 and 525, with statistical difference between the 2 groups (t =- 12. 153, P <0.05). The number of small lymph nodes(diameter≤5 mm) harvested in test group was 985. (2) The numbers of lymph nodes harvested in the anterior, posterior and bilateral mesorectum were 125,696 and 615, respectively. The numbers of lymph nodes harvested in the upper, middle and lower part of the mesorectum were 395,534 and 507, respectively. The metastatic rate of lymph nodes in the upper part of the mesorectum was 18.5% (37/200), which was significantly lower than in the middle [43.5% (87/200)] and lower [38.0% (76/200)] part of the mesoreetum (X2= 9. 414, 6.406, P < 0.05). Two hundred metastatic lymph nodes in 33 patients were harvested, 48.0% (96/200) of which with a diameter of ≤ 5 mm. Twenty percent patients had their TNM stage changed after the retrieval of metastatic small lymph nodes. Conclusions Modified fat clearance technique significandy improves the retrieval of lymph nodes, and more small lymph nodes retrieved can increase the accuracy of staging. Rectal cancer cells have strong tendency to disseminate to the distal mesorectum. Adequate excision of the distal mesorectum is key in controlling the local recurrence.

The paper summarized the explorations of public hospital pilots in the compensation mechanism and identified the following findings.For example,by means of fiscal support of public hospital infrastructure and development spending,cancellation of drug markup,higher service prices, and reformed payment mode of medical insurance,these hospitals have made initial changes at their business operating mechanism, motivation-guidance of compensation, and their makeup of medical revenue.In addition,such hospitals are found with lower cost of medical care per visit,and higher income of medical workers.The authors also pointed out such problems as inflated drug pricing and expenses,lack of scientific pricing mechanism for medical services,vague definition of policy-related losses,and old-fashioned practice of government investment and health insurance payment.Based on such findings,the paper advised to adjust health care prices by stages and to improve the management of health insurance and the coherence of compensation mechanism.

Aim To study the effects of agmatine on the proliferation ability of neural progenitor cells from neonatal rat hippocampus.Methods Hippocampus of neonatal rat was isolated and made into single-cell suspension,which was cultured in serum-free medium and then using CCK-8 kit assay,the survival rate of neurospheres incubated with various concentrations of agmatine and efaroxan.Furthermore,the effect of these drugs was measured with()~3H-thymidine incorporation assay.Results Cells we cultured could continuously proliferate and cultured as floating neurospheres.CCK-8 kit assay revealed that agmatine 1 ?mol?L~(-1) and 10 ?mol?L~(-1) enhanced the survival rate of neural stem cell,and the result alike with()~3H-thymidine incorporation assay.Efaroxan 10 ?mol?L~(-1) inhibit proliferation effect of agmatine on neural stem cell.Conclusion Agmatine was found to increase the proliferation of neural stem cell and efaroxan can block the proliferation effect.It suggested that imidazolineⅠ receptor may be related to the proliferation effect.

Objective To evaluate the prognostic value of microsatellite instability (MSI) in stage Ⅱ colon cancer patients.Methods 120 stage Ⅱ colon cancer patients underwent radical resection in the Department of Colorectal Surgery,Beijing Cancer Hospital from 2000 to 2007.Tissue samples were collected and DNA was extracted for MSI determination using PCR following the Pentaplex panel.Clinical parameters were also combined and analyzed statistically to explore the association between MSI status and clinical parameters.Results The incidence of high frequency of microsatellite instability (MSI-H) was 20.8％ in these 120 stage Ⅱ colon cancer patients.There was a significant correlation between the status of MSI and tumor differentiation (x2 =9.69,P =0.021);However MSI status was demonstrated to be a prognostic factor for disease free survival or overall survival (all P ＞ 0.05).Nor was MSI status associated with tumor relapse or metastasis.Age and preoperative serum CEA level were identified as independent factors for DFS by Cox regression.Conclusion In stage Ⅱ colon cancer patients,MSI status correlates with tumor differentiation,but is not a prognostic factor.

Objective:To evaluate diagnostic value of contrast-enhanced harmonic endoscopic ultrasonography (CEH-EUS) for pancreatic cystic lesions.Methods:Endoscopic and clinical follow-up data of patients with pancreatic cystic lesions diagnosed by EUS in Department of Gastroenterology of the First Affiliated Hospital of Naval Medical University with CEH-EUS video from March 2013 to April 2020 was retrospectively analyzed.Results:A total of 36 patients were included. There were 16 cases of serous cystadenomas (SCA), 10 cases of mucinous cystic neoplasm (MCN), 5 cases of intraductal papillary mucinous neoplasms (IPMN, 3 with complex type, 2 with main pancreatic duct type) and 5 cases of pancreatic pseudocyst (PPC). 87.5%(14/16) of SCA and 86.7%(13/15) of MCN+ IPMN had hyperenhanced cystic wall with obvious peak and similar washout as surrounding tissue, whereas only 20%(1/5) PPC had hyperenhanced cystic wall. The hyperenhancing effect of PPC was significantly lower than that of SCA and MCN+ IPMN ( P=0.0035 and P=0.0048, respectively ). Mural nodules were detected in 17 cases of pancreatic cystic lesions by EUS, of which 3 cases had hyperenhanced mural modules and 14 cases had hypoenhanced mural nodules by CEH-EUS. Patients showing hyperenhanced mural modules were all finally diagnosed as pancreatic malignancy (1 IPMN, 2 MCN), and the accuracy was 100%. Conclusions:CEH-EUS can have a obvious advantage of differentiating pseudocyst and other pancreatic cystic lesions, while not very useful for differentiating SCA and MCN. Pancreatic cystic lesions showing hyperenhanced mural nodules under CEH-EUS may imply malignancy potential.

Objective To investigate the feasibility,safety,and short term efficacy of endoscopicultrasound guided radiofrequency ablation (EUS-RFA).Methods Three patients with advanced,inoperable pancreatic carcinoma underwent EUS-RFA.Under the guidance of EUS,a 22 gauge fine needle was punctured into the pancreatic carcinoma,and 1 Fr radiofrequency (RF) catheter was placed into the cancer through this 22 gauge needle.RFA was applied at 10 watts for 2 minutes,and then 15 watts for another 2 minutes.The second needle's tract was selected and punctured about 1 ～ 1.5 cm apart from the first needle tract,and the ablation was repeated.Results The average age of these 3 patients was 63 years old.Two patients were diagnosed to have pancreatic tail cancer and one was pancreatic body cancer,and the mean diameter of the tumor was 3.6 cm.Pre-operative EUS-FNA confirmed the presence of malignant cells.EUS-RFA was performed three times at an interval of 2 weeks in the first patient and one time in the last two patients.The average session of EUS-RFA of each lesion was 3.67 times.After 2 weeks,EUS showed that the diameter of the lesions was reduced by 13.9％ on average.There were vacuolar degenerations of variable sizes in those lesions.The serum level of CA19-9 was averagely decreased by 46.5％.Abdominal pain was not obviously aggravated.There were no episodes of pancreatitis,perforation or bleeding within 48 hours after the procedure.The mean follow-up time was 49 days,and no complications occurred.Conclusions EUS-RFA can reduce the diameter of pancreatic carcinoma and decrease the serum level of CA19-9,and it is feasible and safe.

Objective To detect the levels of AKAP12 methylation by methylation‐specific high‐resolution melting curve(MS‐HRM ) in peripheral blood in patients with colorectal cancer and investigate its clinical significance .Methods We used MS‐HRM technology to detect the levels of AKAP12 methylation in peripheral blood in 60 lung cancer patients ,and analyzed the relationship between the levels of AKAP12 methylation and pathological parameters of lung cancer patients .Results 34(56 .7% ) of the 60 lung cancer patients were found to be methylated at the AKAP12 promoter region by MS‐HRM ,the methylation levels of 18 cases ranged between 1% -20% ,14 cases ranged between 20% -60% ,2 cases ranged between 60% -100% .There was no significant differences between the levels of AKAP12 methylation and lung cancer patients′age and gender(P>0 .05) .However ,it was signifi‐cantly higher in the patients with high pathological stage and differentiation degree (P<0 .05) .Conclusion AKAP12 promoter re‐gion methylation was related to tumor progression and malignant degree .