Predictive Factors And Surgical Safety Analysis For Pathological Lateral Pelvic Node Metastasis In Rectal Cancer Patients With Clinical Lateral Pelvic Node Metastasis After Neoadjuvant Chemoradiotherapy

Aim There is still no common opinion about lateral pelvic lymph node dissection(LPLND)for rectal cancer patients with clinical LPLN metastasis after neoadjuvant chemoradiotherapy(nCRT).In addition,the adverse reactions such as tissue edema,scar fibrosis and coagulation dysfunction caused by nCRT will further increase the surgical risk of LPLND.Therefore,this study was designed to explore the predictive factors for pathological LPLN metastasis in rectal cancer patients with clinical LPLN metastasis after nCRT,and the safety and feasibility of LPLND after nCRT.Method From January 2010 to February 2019,consecutive rectal cancer patients with clinical LPLN metastasis after nCRT who accepted total mesorectal excision(TME)and LPLND were systematically reviewed in our institution.The general information,perioperative outcomes,and pathological outcomes were collected and analyzed.Results In all,76 consecutive cases were included in this study:53(69.7%)patients accepted unilateral LPND,and 23(29.3%)patients accepted bilateral LPND.The pathological results showed that LPLN metastasis was found in 13(17.1%)patients.The mean operative time was 291.4±63.3 min,and the mean intraoperative blood loss was 105.3 ±22.1 ml.Severe complications occurred in 11 patients(14.5%)during the perioperative period.Multivariate logistic regression analysis showed that the post-nCRT lateral pelvic node size≥5 mm(OR=7.67,95%CI=1.45-40.63,P=0.017)and mucinous/signet-ring adenocarcinoma(OR=4.60,95%CI=1.11-19.08,P=0.035)were independent risk factors of pathological LPLN metastasis.Conlusion LPLN short diameter≥5mm after nCRT and mucinous/signet-ring adenocarcinoma were independent prediciting factors of pathological LPLN metastasis after nCRT for rectal cancer patients with clinical LPLN metastasis,and patients with these characteristics may benefit from LPLND.In addition,TME+LPLND after nCRT is safe and feasible,and does not increase the incidence of perioperative complications.