Predictive Value Of Serum IL-6 Level After Neoadjuvant Hormonal Therapy In Biochemical Recurrence Of Prostate Cancer Patients Undergoing Radical Prostatectomy

Objective: To investigate the value of serum interleukin-6(IL-6)levels after neoadjuvant hormonal therapy(NHT)in predicting biochemical recurrence of patients with prostate cancer(PCa)after radical prostatectomy(RP).Methods: We collected clinicopathologic data of 294 PCa patients who received RP after NHT from the Affiliated Hospital of Qingdao University and the Affiliated Cancer Hospital of Fudan University from 2011 to 2014.Enzyme-linked immunosorbent assay was used to measure the preoperative serum IL-6 concentration of the patients.According to the median concentration of IL-6,the patients were divided into high-level group and low-level group.The Student’s t-test and Chi-square test were used to compare the differences in clinical and pathological characteristics between the two groups,and the survival differences between the two groups were analyzed using Kaplan-Meier survival analysis.A multivariate Cox proportional risk regression model was used to identify the impact of post-NHT IL-6 level on the prognosis.Results: There were no significant differences between the high-level group and low-level group in terms of age,body mass index,smoking,hypertension,diabetes,positive incisal margin,seminal vesicle invasion and Gleason scores(P > 0.05).Compared with low-level group,the high-level group showed significantly increased capsule invasion rate(χ2=3.890,P < 0.05),lymph node positive rate(χ2=13.397,P < 0.01),pathological T-stage(χ2=4.613,P< 0.05),and prostate-specific antigen(PSA)level(χ2=11.15,P < 0.01).Kaplan-Meier survival analysis showed that the probability of biochemical recurrence in the high-level group was significantly higher than that in the low-level group(P < 0.05).The multivariate Cox proportional risk regression model was used to identify the independent risk factors for postoperative biochemical recurrence,including high IL-6 level(HR=1.531,95%CI=1.011-2.318,P < 0.05),lymph node metastasis(HR= 1.818,95%CI = 1.093-3.025,P < 0.05),high tumor T stage(HR= 1.769,95%CI=1.132-2.762,P < 0.05),and PSA ≥20ng/ml(HR = 3.108,95%CI = 1.421-6.799,P < 0.05).Conclusion: Increased serum IL-6 level after NHT in prostate cancer patients after RP is associated with earlier biochemical recurrence and poor prognosis.IL-6 can predict the biochemical recurrence of RP after operation,which is helpful for making informed clinical decision.In addition,lymph node metastasis,tumor T stage and PSA ≥ 20ng/ml were independent prognostic risk factors in patients after RP.