Objective To investigate the role of double contrast-enhanced ultrasonography (DCUS) in the diagnosis of rectal gastrointestinal stromal tumors (GISTs). Methods In eleven patients with rectal GISTs before surgery, gastrointestinal ultrasound contrast agent were injected into rectal lumen and tumor’s two dimensional ultrasound features were analyzed. Microbubbles were injected into the vein to investigate the feature of lesion microcirculation perfusion. After the surgery, according to the tumor diameter and mitotic count, rectal GISTs were classified as very low-risk, low-risk, intermediated-risk and high-risk tumors. The very low-risk and low-risk tumors were grouped together as one group while the intermediated-risk and high-risk tumors were grouped together as another group. According to ultrasound performance and pathological type, ultrasonic features of rectal GISTs with different risk levels were estimated. Results Among all rectal GISTs cases, 63.6%(7/11) were low-risk. Under DCUS, the tumor diameter was less than 5 cm, with regular round, hypoechogenicity, uniform low enhancement and less internal liquefaction necrosis. For the 36.4%(4/11) high-risk cases, under DCUS, the tumor diameter was≥5 cm, with irregular round or lobulation, mixed hyperechogenicity and hypoechogenicity, nonuniform high enhancement, large blood vessel and common liquefied necrosis region. The biological behavior of rectal GISTs was relevant to lesion size, liquefaction necrosis and enhancement mode of ultrasound contrast and irrelevant to the bound and shape of lesion. The accuracy of DCUS and contrast-enhanced ultrasonography were 90.9%(10/11) and 72.7%(8/11) respectively. Conclusions DCUS is considered as an effective tool in diagnosingrectal GISTs and can get useful information of the biological characteristics. It has great value for the diagnosis and treatment of rectal GISTs.

Objective To assess the validity of transanal local excision for stage Ⅰ low rectal carcinoma.Methods The clinical data of 93 patients with stage Ⅰ low rectal carcinoma who underwent transanal excision (group A,n=45)or radical resection(group B,n=48)were retrospectively analyzed.Twenty-four T1 patients and 21 T2 patients in group A received postoperative adjuvant radiation therapy and adjuvant chemoradiotherapy,respectively.All patients in group B received radical surgery only.The 5-year survival rates,recurrence rates,and postoperative complications between the 2 groups were compared.Results The 5-year survival rates were 100%(24/24)for T1 patients,86%(18/21)for T2 patients in group A,and 100%(18/18)for T1 patients,93%(28/30)for T2 patients in group B,with no significantly statistical difference between the 2 groups(P＞0.05).The recurrence rates were 4%(1/24)for T1 patients,19%(4/21)for T2 patients in group A,and 0(0/18)for T1 patients,7%(2/30)for T2 patients in group B,with no significance between the 2 groups(P＞0.05).The incidence of postoperative complications in group A was 2%(1/45),which was significantly lower than that of 15%(7/48))in group B(P＜0.05).Conclusions Transanal local excision of early low rectal carcinoma,combined with postoperative chemotherapy for T1 patients or chemoradiotherapy for T2 patients, results in a low complication rate and good sphincter function,and provides satisfactory local control and 5-year survival rates.

Objective To evaluate the preoperative T staging value of rectal carcinoma by using double contrast-enhanced ultrasonography (DCUS).Methods 71 patients with rectal carcinoma were examined by ultrasound after infusing contrast agent and bolus injection of SonoVue preoperatively.The border,shape and perfusion patterns of the tumor were observed.After surgery,the T staging made by DCUS and perfused contrast-enhanced ultrasonography (PCUS) was compared with final pathologic results respectively.Results The accuracy of PCUS and DCUS in determining the T stage of rectal carcinoma were 71.8％(T1 72.7％％,T250.0％,T374.4％,T476.9％) and 85.9％(T190.9％,T275.0％,T387.1％,T484.6％) respectively.The difference between these two methods was statistically significant (P ＜0.05).Conclusions DCUS is a new valuable method for T staging of rectal carcinoma with its high accuracy preoperatively.

ObjectiveTo study serum proteomic fingerprints of colorectal cancer during onset and progression and to screen tumor markers related to prognosis.Methods Serum from colorectal cancer patients, non-cancer patients, and healthy control were profiled using WCX ProteinChip or magnetic beads and analyzed by mass spectrometry. Results Seven protein peaks were found related to colorectal cancer. Several peaks were closely related to lymph node metastasis, distal organ metastasis and decreased after surgery. The diagnostic model composed of 3398.3、5477.1、8453.9 u can detect CEA negative colorectal cancer in 100%. Conclusion Protein fingerprinting technology (PFT) in conjunction with bioinformatics can significantly identify novel biomarkers in the serum of colorectal cancer patients with potential values for prognostic evaluation, detection of CEA negative colorectal cancer and changing its progression.

Objective To introduce a novel technique of intracolonic shunt procedure used in the anus - preserving operation for acute intestinal obstruction resulted from cancer at low and middle portions of rectum and assess the clinical significance. Methods In total, 81 patients with acute obstruction of low and middle portion of rectum caused by cancer were randomly ( random number) divided into control group and study group. In control group, 42 patients were operated with preventive transverse colonostomy or terminal ileum stoma after low proximal resection of rectum involved in cancer, while 39 patients were operated with intracolonic shunt procedure by using a biodegradable anastomosis ring and a condom placed 5 cm above anastomosis for protection in study group. Results There were no significant differences in sex, age, tumor site, tumor size and the distance from anstomosis to anal-edge between two groups. In both groups, the bowel movement resumed in 2 ~ 5 days after operation (P > 0.05). In study group, the rate of anastomosis leakage was 7.7% (3/39), and leakages were treated with drainage for 7.1 days in average to be healed, and the biodegradable anastomosis ring detached and were discharged in 14 -23 days (17 days in average), and there were no complications of drainage happened. The anastomotic stenosis occurred in three patients (7. 7% ) within 6 months after operation. In control group, 11.9% patients (5/42) had anastomosis leakage and they treated with drainage for 18.2 days in average to get the leakage healed, and 35. 7% patients (15/42) had stoma complications, and anastomotic stenosis happened in 28.6% patients (12/42) within 6 months after operation, and 7. 1% patients need another operation because of severe anastomosis stenosis. There were no significant differences in rate of anastomosis leakage between tow groups ( P > 0. 05), but there were significant differences in drainage days after anstomosis leakage happened and 6 - months anastomosis stenosis between two groups (P<0.05). Conclusions In the anus -preserving operation for acute intestinal obstruction at low and middle portions of rectum caused by cancer , the intracolonic shunt procedure is convenient and safty, and reduces the hazard incurred by anastomosis leakage and anastomosis stenosis compared with classic stoma operation.