Analysis Of The Correlative Factors Of Immunohistochemical Markers Alternation After Neoadjuvant Therapy

Objective:To observe the discordance of immunohistochemical results in neoadjuvant patients before and after neoadjuvant therapy(NAT),and to investigate the factors associated with the alternation of immunohistochemical results after NAT.Methods:The clinical and pathological data of a total of 237 breast cancer patients who received NAT at the Department of Breast Surgery,Second Hospital of Jilin University from January 2017 to January 2021 were retrospectively collected.To observe the phenomenon describing the alteration of immunohistochemical biomarkers ER,PR and HER2 expression after NAT,the Mc Nemar-Bowker test was used to analyze the discordance of ER,PR,HER2 expression before and after NAT;the Pearson chi-square test or the chi-square test with consecutive correction was used to verify that ER,PR,HER2 expression after NAT was correlated with factors including patients’ body mass index(BMI)at diagnosis,age at diagnosis,menopausal statement,T-stage of surgical tumor after treatment,and N-stage after treatment.Logistic regression was used to analyze the factors influencing the positive to negative and negative to positive conversion of biomarkers.Results:Discordance of ER and PR expression profiles and molecular subtype of patients pre-and post-NAT were statistically significant(P<0.05,P<0.05,P<0.01).Discordance of PR expression status after NAT was correlated with postoperative pathological N stage after NAT(P=0.040),and patients with pN stage 0,1,or 2 were less likely to have altered PR expression status after NAT and are more inclined not to have altered status compared with patients with pN stage ≥3.Obesity at diagnosis had a significant effect on molecular staging discordance after NAT(P=0.033),and patients with higher BMI at diagnosis are more tended to undergo molecular staging alternation after NAT(P=0.019);whether age was greater than or equal to 50 years or menopausal statement at diagnosis did not show significance in the sample(P>0.05).Postoperative pathological N stage after NAT was correlated with molecular subtype alternation after NAT,and patients with pN stage 0 and1 were less likely to have molecular typing alternations after NAT compared with patients with pN stage ≥3.Conclusion:The expression status of IHC biomarkers ER,PR and HER2 appeared to change after NAT,with alterntion in ER,PR and molecular typing reported to be statistically significant.In the correlation factor analysis,it was found that altered PR expression status after NAT was associated with a greater tendency to alter PR expression status after NAT in patients with pN stage ≥3 compared to patients with lower pN stage;whether BMI ≥24 at diagnosis was significantly correlated factor of molecular typing alteration,and the larger the BMI,the higher the likelihood of molecular typing alteration after NAT;altered molecular typing after NAT was also associated with postoperative N stage,indicating patients with pN stage ≥3 were more likely to have altered molecular type after NAT compared to patients with lower pN stage.