Clinical efficacy and prognosis of simultaneous resection of synchronous colorectal liver metastasis in patients admitted in different phases / 中华消化外科杂志

Objective:To investigate the clinical efficacy and prognosis of simultaneous resection of synchronous colorectal liver metastasis in patients admitted in different phases.Methods:The retrospective cohort study was conducted. The clinicopathological data of 346 patients who underwent simultaneous resection of synchronous colorectal liver metastasis in the First Affiliated Hospital of Naval Medical University (Changhai Hospital of Shanghai) from January 2000 to April 2021 were collected. There were 217 males and 129 females, aged (58±12)years. Patients under-went simultaneous resection of synchronous colorectal liver metastasis. Observation indicators: (1) clinicopathological features of patients with synchronous colorectal liver metastasis in 2000?2010 and 2011?2021; (2) surgical and postoperative situations of patients with synchronous colorectal liver metastasis in 2000?2010 and 2011?2021; (3) analysis of prognosis of patients with synchro-nous colorectal liver metastasis in 2000?2010 and 2011?2021. Follow-up was conducted using telephone interview or outpatient examination to detect survival of patients. The follow-up was performed once every 3 months, including blood routine test, liver and kidney function test, car-cinoembryonic antigen (CEA) test, CA19-9 test, abdominal B-ultrasound examination, and once every 6 months, including chest computed tomography (CT) plain scan, liver magnetic resonance imaging (MRI) and/or CT enhanced scan, abdominal or pelvic MRI and/or CT enhanced scan, within postoperative 2 year. The follow-up was performed once every 6?12 months within postoperative 2?5 years including above reexaminations. Electronic colonoscopy was performed once a year after operation. The follow-up was up to November 12, 2021. Measurement data with normal distribution were represented as Mean± SD, and comparison between groups was conducted using the t test. Measurement data with skewed distuibution were represented as M(range). Count data were described as absolute numbers, and comparison between groups was conducted using the chi-square test. Comparison of ordinal data was conducted using the rank sum test. Kaplan-Meier method was used to calculate survival rates and draw survival curves, and Log-Rank test was used to conduct survival analysis. Results:(1) Clinicopathological features of patients with synchronous colorectal liver metastasis in 2000?2010 and 2011?2021. Of the 346 patients, 59 cases underwent simultaneous resection within 2000?2010 and 287 cases underwent simultaneous resection within 2011?2021. The gender (males and females), cases with or without fundamental diseases, cases with the number of lymph nodes harvested in primary lesion as <12 or ≥12, the tumor diameter of primary lesion, the tumor diameter of liver metastasis lesion, the number of liver metastasis lesions, cases with or without preoperative treatment, cases with or without postoperative treatment, cases with adjuvant therapy as perioperative treatment, surgery or other treatment were 47, 12, 36, 23, 19, 40, (5.5±2.4)cm, (2.1±0.7)cm, 1.6±0.5, 59, 0, 16, 16, 0, 16, 43 in patients admitted in 2000?2010, respectively. The above indicators in patients admitted in 2011?2021 were 170, 117, 121, 166, 58, 229, (4.2±2.0)cm, (3.0±2.0)cm, 1.9±1.4, 208, 79, 34, 235, 74, 29, 184, respectively. There were significant differences in the above indicators between patients admitted in 2000?2010 and 2011?2021 ( χ2=8.73, 7.02, 4.07, t= 4.40, ?6.04, ?3.10, χ2=21.05, 28.82, 26.68, P<0.05). (2) Surgical and postoperative situations of patients with synchronous colorectal liver metastasis in 2000?2010 and 2011?2021. Cases with surgical methods as complete open surgery or laparoscopy combined with open surgery, the operation time, time to postoperative initial liquid food intake, cases with or without postoperative complications, cases with postoperative duration of hospital stay as ≤10 days or >10 days were 58, 1, (281±57)minutes, (5±1)days, 33, 26, 14, 45 in patients admitted in 2000?2010, respec-tively. The above indicators in patients admitted in 2011?2021 were 140, 147, (261±82)minutes, (3±1)days, 233, 54, 198, 89, respectively. There were significant differences in the above indicators between patients admitted in 2000?2010 and 2011?2021 ( χ2=49.04, t=2.24, 7.53, χ2=17.56, 26.02, P<0.05). There was no death in the 346 patients. (3) Analysis of prognosis of patients with synchro-nous colorectal liver metastasis in 2000?2010 and 2011?2021. Of the 346 patients, 295 cases were followed up for 47(range, 1?108)months. Of the 29 patients admitted in 2000?2010 who were followed up, there were 27 cases died. The median survival time, 1-, 3-, 5-year overall survival rates, 1-, 3-, 5-year disease free survival rates of patients admitted in 2000?2010 were 18.0 months (95% confidence interval as 12.7?23.3 months), 82.8%, 11.5%, 3.8%, 53.6%, 8.3%, 4.2%, respec-tively. Of the 266 patients admitted in 2011?2021 who were followed up, there were 109 cases died. The median survival time, 1-, 3-, 5-year overall survival rates, 1-, 3-, 5-year disease free survival rates of patients admitted in 2011?2021 were 54.0 months (95% confidence interval as 38.1?70.4 months), 93.3%, 61.8%, 47.0%, 68.2%, 33.7%, 28.3%, respectively. There were significant differences in overall survival rate and disease free survival rate between patients admitted in 2000?2010 and 2011?2021 ( χ2=47.57, 9.17, P<0.05). Conclusions:With the increase of the operation volume of simultaneous resection of synchronous colorectal liver metastasis, the operation time, time to postoperative initial liquid food intake, postoperative duration of hospital stay and postoperative complications have significantly decreased, while the overall survival rate and disease free survival rate have significantly increased.

Clinical efficacy of conformal sphincter preservation operation versus intersphincteric resection in the treatment of low rectal cancer / 中华消化外科杂志

Objective:To investigate clinical efficacy of conformal sphincter preservation operation (CSPO) versus intersphincteric resection (ISR) in the treatment of low rectal cancer.Methods:The retrospective cohort study was conducted. The clinicopathological data of 183 patients with low rectal cancer who were admitted to two medical centers (117 in the Changhai Hospital of Naval Medical University and 66 in the Huashan Hospital of Fudan University) from August 2011 to April 2020 were collected. There were 110 males and 73 females, aged (57±11)years. Of 183 patients, 117 cases undergoing CSPO were allocated into CSPO group, and 66 cases undergoing ISR were allocated into ISR group, respectively. Observation indicators: (1) surgical situations of patients with low rectal cancer in the two groups; (2) postoperative complications of patients with low rectal cancer in the two groups; (3) follow-up; (4) influencing factors for prognosis of patients with low rectal cancer; (5) influencing factors for satisfaction with the anal function of patients with low rectal cancer. Follow-up was conducted using outpatient examination, questionnaire and telephone interview to determine local recurrence, distal metastasis, survival, stomal closure, satisfaction with the anal function of patients. Measurement data with normal distribution were represented as Mean±SD, and comparison between groups was analyzed using the t test. Measurement data with skewed distribution were represented as M (range). Count data were described as absolute numbers or percentages, and comparison between groups was analyzed using the chi-square test. Comparison of ordinal data was analyzed using the rank sum test.The Kaplan-Meier method was used to draw survival curves, and life table method was used to calculate survival rates. Log-rank test was used for survival analysis. Univariate analysis was performed using the linear regression. Variables with P<0.10 in the univariate linear regression analysis were included for multivariate analysis. Multivariate analysis was performed using the COX stepwise regression model and linear regression analysis. Results:(1) Surgical situations of patients with low rectal cancer in the two groups: cases with laparoscopic surgery, operation time, volume of intraoperative blood loss, distance from tumor to distal margin, cases with postoperative chemotherapy, duration of postoperative hospital stay were 44, (165±54)minutes, (142±101)mL, (0.6±0.4)cm, 76, (6.6±2.5)days for the CSPO group, respectively, versus 55, (268±101)minutes, (91±85)mL, (1.9±0.6)cm, 9, (7.9±4.7)days for the ISR group, showing significant differences between the two groups ( χ2=35.531, t=8.995, -3.437, -3.088, χ2=44.681, t=2.267, P<0.05). (2) Postoperative complications of patients with low rectal cancer in the two groups: 19 patients in the CSPO group had complications. There were 6 cases with grade Ⅰ complications, 12 cases with grade Ⅱ complications, 1 case with grade Ⅲb complication. Fourteen patients in the ISR group had complications. There were 4 cases with grade Ⅰ complications, 7 cases with grade Ⅱ complications, 1 case with grade Ⅲa complication, 2 cases with grade Ⅲb complications. There was no significant difference in the postoperative complications between the two groups ( χ2=0.706, P>0.05). Patients with complications in the two groups were improved after symptomatic and supportive treatment. There was no perioperative death in the postoperative 30 days of the two groups. (3) Follow-up: 183 patients received follow-up. Patients of the CSPO group and ISR group were followed up for (41±27)months and (37±19)months, respectively, showing no significant difference between the two groups ( t=-1.104, P>0.05). There were 2 cases with local recurrence and 9 cases with distal metastasis of the CSPO group, respectively, versus 3 cases and 4 cases of the ISR group, showing no significant difference between the two groups ( χ2=1.277, 0.170, P>0.05). The 3-year disease-free survival rate and 3-year total survival rate were 84.0% and 99.0% for the CSPO group, versus 88.6% and 92.8% for the ISR group, showing no significant difference between the two groups ( χ2=0.218, 0.002, P>0.05). The stomal closure rate was 92.16%(94/102) and 96.97%(64/66) for 102 patients of CSPO group and 66 patients of ISR group up to postoperative 12 months,respectively, showing no significant difference between the two groups ( χ2=1.658, P>0.05). Of the 8 cases without stomal closure in the CSPO group, 2 cases refused due to advanced age, 4 cases subjectively refused, and 2 cases were irreducible due to scar caused by radiotherapy. Two cases in the ISR group had no stomal closure including 1 case of postoperative liver metastasis and 1 case of subjective refusal. There were 92 and 61 patients followed up to 12 months after stomal closure, of which 75 cases and 38 cases completed questionnaires of satisfaction with the anal function. The satisfaction score with the anal function was 6.8±2.8 and 5.4±3.0 for CSPO group and ISR group, respectively, showing a significant difference between the two groups ( t=-2.542, P<0.05). Fifty-four cases in the CSPO group and 21 cases in the ISR group had satisfaction score with the anal function >5, showing no significant difference between the two groups ( χ2=3.165, P>0.05). (4) Influencing factors for prognosis of patients with low rectal cancer: results of COX stepwise regression analysis showed that gender and pT staging were independent influencing factors for disease-free survival rate of patients with low rectal cancer ( hazard ratio=2.883, 1.963, 95% confidence interval as 1.090 to 7.622, 1.129 to 3.413, P<0.05). Gender and pT staging were independent influencing factors for total survival rate of patients with low rectal cancer ( hazard ratio=10.963,3.187, 95% confidence interval as 1.292 to 93.063, 1.240 to 8.188, P<0.05). (5) Influencing factors for satisfaction with the anal function of patients with low rectal cancer: results of univariate analysis showed that surgical method and tumor differentiation degree were related factors for satisfaction with the anal function of patients with low rectal cancer (partial regression coefficient=1.464, -1.580, 95% confidence interval as 0.323 to 2.605, -2.950 to -0.209, P<0.05). Results of multivariate analysis showed that surgical method, tumor differentiation degree and preoperative radiotherapy were independent influencing factors for satisfaction with the anal function of patients with low rectal cancer (partial regression coefficient=1.637, -1.456, -1.668, 95% confidence interval as 0.485 to 2.788, -2.796 to -0.116, -2.888 to -0.447, P<0.05). Conclusion:Compared with ISR, CSPO can safely preserve the anus in the treatment of low rectal cancer, without increasing the incidence of postoperative complications, which can also guarantee the oncological safety and improve the postoperative anal function.

A Preliminary study on the preoperative risk score system for simultaneous operation for patients with colorectal cancer and liver metastases / 中华肝胆外科杂志

Objective:This study aims to analyze the prognosis of patients who underwent a simultaneous operations for colorectal cancer and liver metastases, and to establish a prognostic scoring system for these patients.Methods:From January 2010 to March 2019, the clinicopathological data of patients with colorectal cancer and liver metastases simultaneously operated at Shanghai Changhai Hospital were collected. The clinicopathological prognostic factors on tumor recurrence and survival outcomes on follow-up were analyzed. Single and multiple factors Cox regression analyses were used to determine the risk factors which affected the prognosis of patients. Using the risk factors of poor prognosis on Cox analysis, 1 point was given to each risk factor. Patients were then divided into different groups according to the different total scores. The median overall survival and disease-free survival of each group were analyzed.Results:Of 234 patients included in this study, there were 126 males and 108 females. The average age was (57.4±10.8) years. The median survival was 44.85 months. The 1-, 3-, and 5-year survival rates of the whole group were 87.3%, 55.2%, and 22.9%, respectively. Primary tumor in right colon, preoperative carcinoembryonic antigen ≥200 ng/ml, multiple liver metastases, and poorly differentiated adenocarcinoma/mucinous adenocarcinoma were independent risk factors of poor prognosis. After 1 point was given to each of the above 4 items, patients were then divided into the low-risk (0-1) and high-risk (2-4) groups. The median survivals of patients in the low-risk group ( n=174) and high-risk group ( n=60) were 53 months and 29 months, respectively. The corresponding median disease-free survivals were 21.34 months and 8.48 months, respectively. The differences between the 2 groups were significant ( P<0.05). Conclusion:The results of this study preliminary established a predictive scoring system for patients with simultaneous colorectal cancer and liver which can play a role in selecting treatment options for these patients.

Open reduction and fixation with cannulated screws via the modified Burks-Schaffer approach versus arthroscopic EndoButton plating for avulsion fracture of the tibial attachment of the posterior cruciate ligament / 中华创伤骨科杂志

Objective To compare the clinical outcomes between open reduction and fixation with cannulated screws via the modified Burks-Schaffer approach versus arthroscopic EndoButton plating for avulsion fracture of the tibial attachment of the posterior cruciate ligament(PCL).Methods From February 2013 to August 2017,41 patients with acute displaced avulsion fracture of the tibial PCL attachment were treated operatively at Department of Trauma Surgery,The Affiliated Hospital to Qingdao University.They were 24 men and 17 women,aged from 18 to 65 years (average,39 years).The lefi knee was injured in 22cases and the right knee in 19.They were divided into 2 groups according to their different fixation methods.The open reduction and fixation group (23 cases) received open reduction and fixation with cannulated screws via the modified Burks-Schaffer approach while the arthroscopic group (18 cases) arthroscopic Endobutton plating.The 2 groups were compared in terms of operation time,bleeding,objective knee scores and knee range of motion (ROM) after operation.Results All the 41 patients were followed up from 23 to 40months (average,27.2 months).Their follow-up revealed no incision infection,malunion,nonunion or loosening of the implants.Their knee X-ray films at the final follow-ups showed bony union of all the avulsion fractures.There were significant differences between the open reduction and fixation group and the arthroscopic group in operation time (52.6±7.3 min versus 86.8±9.2 min) and bleeding (63.9±12.7 mL versus 19.7 ± 10.2 mL) (P ＜ 0.05).There was no significant difference in the objective knee scores or knee ROM between the 2 groups (P ＞ 0.05).Conclusions Both open reduction and cannulated screw fixation via the modified Burks-Schaffer approach and arthroscopic EndoButton plating can achieve satisfactory clinical outcomes in the treatment of avulsion fracture of the tibial PCL attachment.Although the 2 methods make no significant differences in stability of the knee joint or in clinical scores,the latter leads to less bleeding and the former shorter operation time.

A single center retrospective study on surgical efficacy of T3NxM0 middle-low rectal cancer without neoadjuvant therapy / 中华胃肠外科杂志

OBJECTIVE@#To investigate the surgical efficacy and prognostic factors of T3NxM0 middle-low rectal cancer without neoadjuvant therapy.@*METHODS@#Clinical data of patients with middle-low rectal cancer undergoing TME surgery with T3NxM0 confirmed by postoperative pathology at Colorectal Surgery Department of Changhai Hospital from January 2008 to December 2010 were analyzed retrospectively.@*INCLUSION CRITERIA@#(1)no preoperative neoadjuvant chemoradiotherapy (nCRT); (2) complete preoperative evaluation, including medical history, preoperative colonoscopy or digital examination, blood tumor marker examination, and imaging examination; (3) distance between tumor lower margin and anal verge was ≤ 10 cm; (4) negative circumferential resection margin (CRM-). Finally, a total of 331 patients were included in this study. According to the number of metastatic lymph node confirmed by postoperative pathology, the patients were divided into N0 group without regional lymph node metastasis (190 cases) and N+ group with regional lymph node metastasis (141 cases). The perioperative conditions, local recurrence, distant metastasis and prognostic factors were analyzed.@*RESULTS@#Compared to N0 group in the perioperative data, N+ group had higher ratio of tumor deposit [29.8%(42/141) vs. 0, χ²=64.821, P0.05). The median follow-up period was 73.4 months. The merged 5-year local recurrence rate was 2.7%(9/331), 5-year distant metastasis rate was 23.3% (77/331), 5-year disease-free survival (DFS) rate was 73.4%, and 5-year overall survival (OS) rate was 77.2%. Multivariate analysis showed that lymph node metastasis (HR=3.120, 95%CI: 1.918 to 5.075, P<0.001), nerve invasion (HR=0.345, 95%CI: 0.156 to 0.760, P=0.008) and vascular invasion (HR=0.428, 95%CI: 0.189 to 0.972, P=0.043) were independent risk factors for DFS in patients with T3NxM0 rectal cancer after operation. Preoperative carcinoembryonic antigen level (HR=1.858, 95%CI:1.121 to 3.079, P=0.016), lymph node metastasis (HR=3.320, 95%CI: 1.985 to 5.553, P<0.001) and nerve invasion (HR=0.339, 95%CI: 0.156 to 0.738, P=0.006) were independent risk factors for OS in patients with T3NxM0 rectal cancer after operation.@*CONCLUSIONS@#Optimal local control rate of middle-low rectal cancer patients with T3NxM0 and CRM- can be achieved by standard TME surgery alone. For patients with preoperative elevated blood carcinoembryonic antigen level, regional lymph node metastasis, or neurovascular invasion confirmed by pathology after surgery, adjuvant chemoradiotherapy should be actively applied after surgery to improve prognosis.

Preliminary investigation of intramural lateral spread distance in pull-through conformal resection of low rectal cancer / 中华胃肠外科杂志

<p><b>OBJECTIVE</b>To investigate the intramural lateral spread distance in low rectal cancer in order to provide basis for safety lateral resection margin of pull-through conformal resection (PTCR).</p><p><b>METHODS</b>The patients with low rectal cancer who received low anterior resection or abdominal-perineal resection in Changhai Hospital from December 2015 to March 2016 were enrolled and Surgical specimens were collected. After the specimens were fixed in 10% formaldehyde for 24 hours, a piece of tissue that was 1.5 cm in length and 0.5 cm in width from the edge of tumor was cut. The tissue was obtained in the direction of 3, 5, 7 and 9 o'clock clockwise. The distance of intramural lateral spread was measured in the specimens and the risk factors were analyzed.</p><p><b>RESULTS</b>A total of 83 specimens were collected and the overall proportion of intramural lateral spread was 71.1%(59/83). The rate of lateral spread from 3 to 9 o'clock was 34.9%(29/83), 26.5%(22/83), 32.5%(27/83) and 37.3%(31/83) respectively, and the difference was not statistically significant(χ=2.444 9, P=0.485 3). The median distance of lateral spread in each direction was all 0 mm and the quartile range was 1 mm, 0.5 mm, 0.55 mm and 1 mm respectively. The 5th percentile (P5) of each direction was all 0 mm and the 95th percentile(P95) of each direction was 2.5 mm, 1.6 mm, 2.6 mm, 2.5 mm, respectively and the difference was not statistically significant either(χ=5.331 0, P=0.148 9). The rate of lateral spread of T1, T2, T3 and T4 was 0/4, 58.3%(14/24), 83.0%(44/53) and 1/2 respectively, and there was significant difference(P=0.005 0). The multivariate analysis indicated that T stage (P=0.002 2, OR=3.741, 95% CI: 1.606-8.716) was the risk factor of intramural lateral spread.</p><p><b>CONCLUSIONS</b>The intramural lateral spread does exist in low rectal cancer and T stage is the risk factor of lateral spread. The lateral resection margin should be 5 mm from the tumor edge at least when PTCR is performed.</p>

In vitro fabrication of tissue-engineered osteochondral composite graft in a home-made double-chamber stirring bioreactor / 中国组织工程研究

BACKGROUND:Articular cartilage injury is often complicated by subchondral bone damage to form osteochondral defects, and its treatment remains a pressing problem in orthopedics. Osteochondral composite grafts fabricated by tissue engineering technology provide a new way to repair osteochondral defects. OBJECTIVE:To explore the feasibility of fabricating osteochondral composite grafts in an independently designed double-chamber stirring bioreactor. METHODS: Goat bone marrow mesenchymal stem cels were seeded into β-tricalcium phosphate scaffolds. The cel/scaffold constructs were subjected to chondrogenic and osteogenic induction simultaneously in the double-chamber stirring bioreactor. According to the applied shear stress, they were divided into dynamic and static culture groups. The proliferation of bone marrow mesenchymal stem cels was detected by MTT test and scanning electron microscope examination. Osteogenesis and chondrogenesis related genes were detected by RT-PCR for the evaluation of chondrogenic and osteogenic differentiation. RESULTS AND CONCLUSION:The bone marrow mesenchymal stem cels in both dynamic and static culturegroups demonstrated satisfactory proliferation and differentiation. Better proliferation and differentiation ability were found in the dynamic culture group. Fabrication of osteochondral composite grafts in the independently.designed double-chamber stirring bioreactor is feasible, which is better under the mechanical stimulus environment than the static environment.

Multivariate analysis of the relationship between free DNA concentration in the blood and prognosis of non-small cell lung cancer / 中国综合临床

Objective To investigate the association of circulating free blood DNA and prognosis of non-small cell lung cancer (NSCLC).Methods Forty-six untreated NSCLC patients and 21 controls were selected as our subjects,and all underwent a 6 years follow-up.The level of circulating free blood DNA was determined by real-time quantitative polymerase chain reaction (qPCR) targeting the human β-globin gene.Overall survival of the patients were analyzed by Kaplan-Meier method and Cox-regression.Results At the end of follow-up,the median free DNA concentration of experimental patients was higher than that of control patients(52 μg/L vs.29 μg/L,P =0.03).The median free DNA concentration of experimental death patients (87％) died was significantly higher than that of still survived patients (59 mg/L vs.25 mg/L,P =0.02).No association of DNA concentration with tumor pathology,clinical stage,age,gender,smoking or pulmonary inflammatory conditions were found in current study.Conclusion For NSCLC patients,the circulating free blood DNA level was negative correlation with the survival of the patients,suggesting that it may be utilized as a prognostic factor for survival analysis.But there is no relationship of free blood DNA concentration with tumor pathology,age,gender,smoking or pulmonary inflammatory conditions.

CT-guided percutaneous lung biopsy diagnosis of diffuse lung diseases / 中国医学影像技术

Objective To assess the diagnostic value of the CT-guided percutaneous lung biopsy in diffuse lung diseases. Methods CT-guided percutaneous lung biopsy was performed using 18G or 20G biopsy needle in 68 patients with diffuse lung diseases. The main imaging changes of these patients included network of diffuse nodular or nodular, diffuse reticular lines shadow and diffuse ground-glass density in the lungs. Results Punctures were successful in all 68 patients, and the diseases were clearly diagnosed, including 19 patients with malignant (9 bronchioloalveolar carcinoma and 10 metastatic carcinoma) and 49 with benign (27 disseminated pulmonary tuberculosis, 8 sarcoidosis, 7 silicosis and coal worker's lung, 2 interstitial pneumonia, 4 pulmonary alveolar proteinosis allergic and 1 pneumonia) lesions. The major complications of puncture were pneumothorax and bleeding, and the incident rate of complications was 17.65%. Conclusion CT-guided percutaneous lung biopsy is a useful, safe technique with low complications, high accuracy rate for the diagnosis of diffuse lung diseases.

A study on the number of lymph node harvested after radical resection of invasive rectal carcinoma / 中华普通外科杂志

Objective To evaluate the number of lymph node harvested during radical resection of invasive rectal carcinoma(stage Ⅰ toⅢ).Methods From January 2000 to June 2008,the pathological data of colorectal carcinoma patients who were operated on were retrospectively reviewed.Exclusion criteria included recurrent colorectal tumor,Tis tumor,R1 or R2 resection,tumor resection transanally or endoscopically,synchronous diseases affecting the surgical procedure for the reetal cancer(familial adenomatous polyposis.synchronous coloreetal carcinoma)and rectal cancer receiving perioperative neoadiuvant chemoradiation.Statistical analysis was performed using Mann-Whitney Test and Chi-Square Test (SPSS 15.0).Results were expressed as mean±SEM.Results A total of 2282 patients were identified.including 1216 cases in the rectal carcinoma group and 1066 cases in the colon carcinoma group.There were no significant difference in gender(719/1216 vs.593/1066,P=0.092)and overall TNM stage (P=0.067)between the two groups.But patients of rectal cancer were younger(58.6±0.4 vs.62.0±0.4.P=0.000).The lymph node retrieval in the rectal carcinoma group was significantly less than that of colon carcinoma group(9.4±0.1 vs.10.5±0.1,P=0.000).There were significantly less rectal cancer patients with a 1ymph node harvest equal to or more than 12 nodes(P=0.000).Patients in the low rectal cancer group(≤7 cm from the anal verge.n=834)had less lymph nodes harvested than the mid-high rectal cancer group(＞7 am and≤15 cm from the anal verge.n=382)(9.2±0.1 vs.9.9±0.2,P=0.009).Conclusion The lymph node harvest in the rectal carcinoma group was significantly less than that in the colon carcinoma group.A new standard may be necessary to define the adequate number of lymph nodes for rectal cancer.