Objective Although chitosan has excellent biocompatibility and biodegradability, it is only soluble in acid solution that is not feasible for application in tissue engineering. The current study is aimed to prepare the carboxymethyl chitosan (CMC) for the purpose of improving the solubility of chitosan to meet the requirement of development of tissue engineering scaffolds. Methods The preparation methods and process conditions, such as the proportion of reactant, reaction temperature, reaction time and so on for three types of carboxymethyl chitosan were studied. Results The results indicated that optimal process conditions of three types of water soluble chitosan were obtained. Conclusion Water solubility of chitosan is greatly improved through carboxymethyl modification, which provides possibilities and foundation for further research.

OBJECTIVETo explore the efficacy prediction of the locally advanced rectal cancer patients, especially those with pathological complete response(pCR), receiving neoadjuvant chemoradiotherapy in order to execute precise preoperative neoadjuvant chemoradiotherapy.

METHODSFrom January 2000 to January 2011, 125 patients diagnosed as locally advanced rectal cancer receiving preoperative neoadjuvant chemoradiotherapy in our department with complete data were enrolled in this study, including 85 males and 40 females with mean age of 54(15 to 77) years old. All the patients received radiotherapy with 46 Gy(23 times) and administered XELOX regimen (oxaliplatin 100 mg/m(2) plus capecitabine 2 000 mg/m(2)) for 2 courses simultaneously, and underwent radical operation 6 to 8 weeks after chemoradiotherapy. The data of these patients were analyzed retrospectively. Pathological remission was divided into 4 grades. Patients achieving grade 4 were defined as pCR, and those achieving above grade 2 were defined as better response. Logistic regression analysis was used to identify significant predictors of pCR.

RESULTSAmong 125 patients, 16(12.8%) achieved pCR status, and 90(72.0%) had better response to the neoadjuvant chemoradiotherapy. Logistic regression analysis showed that age(OR:1.060, P=0.037) and preoperative positive lymph nodes detected by endorectal ultrasonography (OR:0.059, P=0.006) were independent predictors of pCR after neoadjuvant chemoradiotherapy.

CONCLUSIONSPreoperative existence of lymph node metastasis around bowel indicates the poor response to neoadjuvant chemoradiotherapy. Age is associated with pCR in patients receiving neoadjuvant chemoradiotherapy.

Adolescent ; Adult ; Aged ; Antineoplastic Combined Chemotherapy Protocols ; therapeutic use ; Capecitabine ; therapeutic use ; Chemoradiotherapy ; Deoxycytidine ; analogs & derivatives ; therapeutic use ; Female ; Fluorouracil ; analogs & derivatives ; therapeutic use ; Humans ; Lymphatic Metastasis ; Male ; Middle Aged ; Neoadjuvant Therapy ; Neoplasm Staging ; Rectal Neoplasms ; therapy ; Retrospective Studies ; Treatment Outcome ; Young Adult

Surgical resection is the best method for patients with colorectal cancer liver metastases. However, tumor recurrence rate is still high after surgery. Preoperative chemotherapy can help shrink the tumor, test biological behavior, and reduce recurrence rate; but it may also cause liver injury and delay surgery. There is still controversy whether neoadjuvant chemotherapy should be performed and how to select patients from chemotherapy before surgery. Thus, in this article, combined the research progress and the clinical experience of author's center, we discuss this issue in 4 aspects: the development of neoadjuvant chemotherapy; the indications and guideline recommendation for neoadjuvant chemotherapy; the selection of neoadjuvant chemotherapy regimens; common problems in neoadjuvant chemotherapy.

OBJECTIVETo explore the clinicopathological characteristics, efficacy, and prognostic factors for patients with rectal gastrointestinal stromal tumor(GIST).

METHODSClinicopathological and follow-up data of 61 patients with rectal GIST in our department from January 1990 to October 2012 were analyzed retrospectively and pathology specimens were reviewed. Kaplan-Meier method was used to calculate the survival. Univariate analysis and multivariate analysis were performed to investigate the influencing factors of prognosis with Log-rank test and Cox regression model.

RESULTSThere were 42 male and 19 female patients with a median age of 59 years old. Eighteen cases(29.5%) were confirmed preoperatively as GIST by biopsy and 46 cases were diagnosed as GIST by first pathological examination. Fifteen cases(24.6%) were revised as GIST after re-examination of specimes among whom 14 cases had been diagnosed as leiomyoma or sarcoma, and 1 as neurolemmoma. Tumor location was above peritoneal reflection in 12 cases(19.7%) and below peritoneal reflection in 49(80.3%). Fifty-two patients underwent surgery, including 21 extended resections(lymph nodes clearance and combined organs resection simultaneously) and 31 local resections(tumor rejection or partial resection of rectal wall). Eleven patients received preoperative imatinib(400 mg/d). Forty-one cases received imatinib therapy after operation or biopsy diagnosis, including 25 cases who received palliative treatment for postoperative recurrence. Median follow-up time was 55(6 to 391) months and follow-up longer than 2 years was carried out in 46 patients. Overall survival rates of 1-, 2-, 3- , 5-year were 98%, 95.6%, 86.0% and 73.7% respectively. There were no significant differences between local resection group(96.4%, 92%, 83.3% and 77.3%) and extended resection group (100%, 94.7%, 89.50% and 82.6%)(χ(2)=0.004, P=0.947). Univariate analysis showed that survival was only associated with recurrence and metastasis (χ(2)=4.292, P=0.038). Multivariate Cox analysis showed postoperative survival was not associated with any factors(all P>0.05). The 3-year survival rate of patients with postoperative recurrence or metastasis receiving imatinib therapy was better as compared to those who did not received imatinib(82.7% vs. 71.4%).

CONCLUSIONSRectal GIST are more common in the lower rectum. Surgery is the main treatment for rectal GIST. Local complete resection is the mainstay treatment. Extensive resection and lymph node clearance may not improve survival. Imatinib can improve the prognosis of patients with recurrence or metastasis.

Benzamides ; Female ; Gastrointestinal Stromal Tumors ; therapy ; Humans ; Imatinib Mesylate ; Male ; Neoplasm Recurrence, Local ; Piperazines ; Prognosis ; Pyrimidines ; Rectal Neoplasms ; pathology ; therapy ; Retrospective Studies ; Survival Rate

OBJECTIVETo explore clinicopathologic characteristics, surgical features and prognostic factors in patients with primary gastrointestinal lymphoma(PGIL) in order to provide evidence for optimizing surgical treatment.

METHODSClinicopathological data of 57 PGIL patients undergoing abdominal surgery in Sun Yat-sen University Cancer Center between October 1990 and January 2015 were retrospectively collected. The survival rates were compared among patients with different clinicopathologic characteristics by Kaplan-Meier method, while Cox regression model was employed to analyze the prognostic factors.

RESULTSAmong 57 patients, 43 were male and 14 were female, with a median age of 48 (range 16 to 80) years. Seventeen (29.8%) cases were classified as Musshoff I( stage, 19 (33.3%) cases as II( stage, 9 (15.8%) cases as III( stage, and 12(21.1%) cases as IIII( stage. Forty-four (77.2%) cases underwent selective operation, 13(22.8%) cases underwent emergent operation due to acute abdomen. Thirty-two(56.1%) cases had radical resection, 18 (31.6%) cases had partial resection and the rest 7(12.3%) cases failed to perform resection. Four (7.0%) cases received simple surgical operation, and 53 (93.0%) cases received comprehensive treatment, including 5(8.8%) cases with preoperative chemotherapy and surgery, 40 (70.2%) cases with surgery and postoperative chemotherapy, and 8 (14.0%) cases with surgery and perioperative chemotherapy. Stage III( and IIII( accounted for 76.9%(10/13) in patients undergoing emergent operation and accounted for 25.0%(11/44) in patients undergoing selective operation, whose difference was statistically significant (χ=9.503, P=0.002). Univariate prognostic analysis showed that T lymphocyte source pathological cell phenotype (P=0.000), clinical Musshoff stage III( and IIII((P=0.001), emergent operation (P=0.000) and incomplete tumor resection(P=0.007) had worse 5-year overall survival. Multivariate Cox regression analysis indicated that tumor pathological cell phenotype (HR=13.75, 95%CI:3.546-53.308, P=0.000) and surgical timing (HR=7.497, 95%CI:1.163-48.313, P=0.034) were independent prognostic risk factors of patients with stage I( and II(.

CONCLUSIONSSurgical operation is an important part of comprehensive treatment for PGIL. T lymphocyte source and ulcerative lymphoma indicates poorer prognosis.

Objective To preliminarily explore the clinical efficacy of ipsilateral simultaneous pancreas and kidney transplantation (SPK) .Methods Ipsilateral SPK was performed in 40 patients from September 2016 to August 2018 .During a follow-up period of 6 to 29 months ,we summarized the efficacy and complications of the technique .Results Up to now ,38 patients achieved an exceelent clinical efficacy with no major surgical complications .However ,two patients died of severe pneumonia .The postoperative serum levels of creatinine at 3 ,6 ,12 ,24 months were 107 ,102 ,107 ,110 umol/L ;creatinine clearance rate 64 ,67 ,64 ,63 ml/min;fasting glucose 4 .6 ,5 .1 ,4 .6 ,5 .2 mmol/L ;glycated hemoglobin 4 .8％ , 5 .4％ ,4 .9％ ,5 .2％ respectively .And 1/2-year pancrea and kidney graft survival rates both were 92％ . Complications included kidney graft rejection (n= 11) ,pancreas graft rejection (n= 12) ,simultaneous renal & pancreas graft rejection (n=6) ,renal graft DGF (n=1) ,pulmonary infection (n=14) ,urinary tract infections (n=18) ,gastrointestinal bleeding (n=10) diarrhea (n=6) ,splenic venous thrombosis (n=2) ,incomplete ureteric obstruction of renal allograft (n=3) ,urine leakage (n=1) and pancreas allograft dysfunction (n= 2) .There were no severe surgical complications .After aggressive interventions ,all postoperative complications were cured and none required excision of kidney or pancreas .Conclusions Ipsilateral SPK has definite therapeutic efficacy and it is worth wider popularization .