Abstract: Objective:To investigate influencing factors of the number of lymph node harvest after radical resection of colorectal cancer.
Methods:The retrospective casecontrol study was conducted. The clinicopathological data of 227 patients with colorectal cancer who underwent radical resection in People′s Hospital of Changshou Chongqing from June 2010 to June 2016 were collected. The surgical method and resection extention were determined depending on the tumor location showed on imaging examinations, and all patients underwent radical resection and sufficient lymph nodes dissection. Observation indicators: (1) intra and postoperative situations; (2) influencing factors analysis of the number of lymph nodes harvest after radical resection of colorectal cancer; (3) followup and survival situations. Followup using outpatient examination and telephone interview was performed to detect patients′
survival up to October 2016. Measurement data with normal distribution were represented as ±s. Univariate analysis was done using the chisquare test or Fisher exact probability method. Multivariate analysis was performed using the binomial Logistic regression analysis.
Results:(1) Intra and post-operative situation: all the 227 patients underwent successful radical resection of colorectal cancer, including 67 with radical resection of right colon cancer, 16 with radical resection of left colon cancer, 26 with radical resection of sigmoid colon cancer and 118 with radical resection of rectal cancer. Of 227 patients, 118 received laparoscopic surgery, 109 received open surgery including 8 converted to open surgery from laparoscopic surgery.Tumor located in right hemicolon, left hemicolon, sigmoid colon and rectum were respectively detected in 67,16, 26 and 118 patients, same as results of imaging examintions. Operation time, volume of intraoperative blood loss and number of lymph nodes harvest in 227 patients were (192±72)minutes, (94±84)mL and 14±4. Of 8 patients in 227 patients with postoperative complications, 2 received secondary suture due to wound infection, 2 received reoperation due to intestinal obstruction, 1 received transverse colostomy due to anastomotic leakage, and 3 received stoma reconstruction due to stoma retraction. Duration of postoperative hospital stay of 227 patients was (22±9)days. Postoperative pathological examininations: 35 and 192 patients were respectively diagnosed with mucinous adenocarcinoma and nonmucinous adenocarcinoma. Moderate and lowdifferentiated carcinoma and highdifferentiated carcinoma were respectively detected in 47 and 180 patients. (2) The influencing factors analysis of the number of lymph nodes harvest after radical resection of colorectal cancer: univariate analysis showed that tumor location and tumor pathological T stage were related factors affecting the number of lymph node harvest after radical resection of colorectal cancer (x²=10.066, P<0.05). Multivariate analysis showed the tumor location and tumor pathological T stage were independent factors affecting the number of lymph nodes harvest after radical resection of colorectal cancer (OR=1.283, 6.075, 95% confidence interval: 1.031-1.597, 1.215-30.385, P< 0.05). (3) Followup and survival situations: 190 of the 227 patients were followed up for 4-72 months, with a median time of 32 months. During the followup, 21 patients died, 23 patients survived with tumor, and 146 patients survived without disease.
Conclusion:Tumor location and tumor pathological T stage are independent factors affecting the number of lymph node harvest after radical resection of colorectal cancer.