Objective To analyze the clinical efficacy of microwave ablation in the colorectal cancer with simultaneously multiple liver metastases that was initially evaluated as potentially resectable.Methods The patients with potentially resectable colorectal cancer with simultaneous multiple liver metastases treated in the De-partment of General Surgery of the First Affiliated Hospital of Hebei North University,the Center of Minimally Invasive Therapy in Oncology of Traditional Chinese and Western Medicine in Dongzhimen Hospital of Beijing U-niversity of Chinese Medicine,and the Second Department of General Surgery in the Fourth Hospital of Hebei Medical University from October 1,2018 to October 1,2020 were selected in this study.The general data,pathological features,treatment methods,and clinical efficacy of the patients were collected.According to the treatment methods,the patients were assigned into a surgical resection group(conversion therapy + laparoscopic primary resection +hepatectomy)and a microwave ablation group(conversion therapy +laparoscopic primary re-section +microwave ablation).The surgical indicators(operation duration,time to first postoperative anal ex-haust,hospital stay,etc.)and postoperative complications(anastomotic stenosis,anastomotic hemorrhage,incision infection,etc.)were compared between the two groups.The survival period was followed up,including the overall survival period and disease-free survival period,and the survival curves were drawn to analyze the clinical efficacy of the two treatment regimens.Results A total of 198 patients with potentially resectable color-ectal cancer with simultaneous multiple liver metastases were included in this study.Sixty-six patients were cured by neoadjuvant chemotherapy(FOLFOX or FOLFIRI),including 30 patients in the surgical resection group and 36 patients in the microwave ablation group(with 57 tumors ablated).After the first ablation,54(94.74%)tumors achieved complete ablation,and all of them reached no evidence of disease status after re-ablation.The microwave ablation group had shorter operation duration,less intraoperative blood loss,shorter time to first post-operative anal exhaust,shorter time of taking a liquid diet,shorter hospital stay,and lower hospitalization cost than the surgical resection group(all P<0.001).In addition,the microwave ablation group had lower visual analogue scale score(P<0.001)than the surgical resection group.The incidences of complications such as inci-sion infection(P =0.740),anastomotic fistula(P =1.000),and anastomotic stenosis(P =1.000),the over-all survival period(P =0.191),and the disease-free survival period(P =0.934)showed no significant differ-ences between the two groups.Conclusions For patients with colorectal cancer with simultaneous multiple liver metastases initially assessed as potentially resectable,laparoscopic primary resection +surgical resection/microwave ablation after conversion therapy was safe,effective,and had similar survival outcomes.Microwave ablation outper-formed surgical resection in postoperative recovery,economy,and tolerability,being worthy of clinical promotion.

Objective To analyze the sensitivity of ARHGAP8 in predicting the efficacy of neoadjuvant chemotherapy in the patients with locally advanced mid-low colorectal cancer and provide accurate evidence for the treatment of advanced colorectal cancer.Methods The differentially expressed gene ARHGAP8 was screened out by bioinformatics analysis.Cancer tissue and rectal tissue of 68 patients with primary rectal cancer were select-ed.The rectal cancer tissue samples and the rectal tissue samples were collected for clinical validation of ARH-GAP8 expression by quantitative real-time PCR,Western blotting,and immunohistochemistry.The clinical and pathological features such as gender,age,tumor stage,differentiation degree,and pathological type of the pa-tients were collected for functional validation.Forty-four patients with locally advanced mid-low rectal cancer who received neoadjuvant chemotherapy were selected for immunohistochemical examination of ARHGAP8 expres-sion.The expression level of ARHGAP8 was compared between before and after chemotherapy and among different efficacy groups.Results The bioinformatics analysis revealed differences in the expression level of ARHGAP8 between the cancer tissue and rectal tissue(P＜0.001).The expression level of ARHGAP8 was correlated with tumor stage(P=0.024),lymph node metastasis(P=0.007),and age(P=0.005).Quantitative real-time PCR results showed that the mRNA level of ARHGAP8 in the cancer tissue was higher than that in the rectal tis-sue(P＜0.001).Western blotting and immunohistochemistry results demonstrated that the protein level of ARH-GAP8 in the cancer tissue was higher than that in the rectal tissue(P=0.011).The expression of ARHGAP8 was correlated with tumor size(P=0.010)and pathological stage(P=0.005),while it showed no significant association with tumor differentiation degree,lymph node metastasis,liver metastasis,Ki-67,or microsatellite instability expression level.The 44 patients receiving neoadjuvant chemotherapy included 13,8,8,and 15 pa-tients of tumor regression grades 0,1,2,and 3,respectively.Among them,65.91％(29/44)patients showed responses to the treatment.After neoadjuvant chemotherapy,the expression of ARHGAP8 in the cancer tissue was down-regulated in the patients who responded to the chemotherapy(P＜0.001).The response rate in the patients with low protein level of ARHGAP8 was 92.86％,which was higher than that(53.33％)in the patients with high pro-tein level of ARHGAP8(P=0.033).Conclusions ARHGAP8 is highly expressed in the rectal cancer tissue.The pa-tients with locally advanced mid-low rectal cancer and low ARHGAP8 expression are more sensitive to neoadjuvant chemotherapy with the XELOX protocol.ARHGAP8 can serve as a potential biomarker for the occurrence and develop-ment of rectal cancer and an important index for evaluating the efficacy of neoadjuvant chemotherapy with the XELOX protocol in the patients with locally advanced mid-low rectal cancer.