Expression of EGFR in breast cancer and its correlation to molecular subtyping and hormone receptor status / 中华内分泌外科杂志

ABSTRACT

Objective To study the expression of epidermal growth factor receptor 1 (EGFR) protein in breast cancer and its correlation to molecular subtyping and hormone receptor status.Methods 467 cases of breast cancer were included.According to ER,PR,HER2,and Ki-67 status,the cases were categorized into 4 molecular subtypes,including 185 cases of luminal A,109 cases of luminal B,76 cases of HER2-enriched,and 70 cases of triple-negative breast cancer (TNBC).According to ER and PR status,the cases were divided into 4 subtypes,including 240 cases of ER+/PR+,50 cases of ER+/PR-,4 cases of ER-/PR+,and 173 cases of ER-/PR-.Results EGFR protein expression rates in Luminal A,Luminal B,HER2-enriched and TNBC were 16.8％(31/185),54.1％(59/109),97.4％(74/76),78.6％(55/70),respectively.The EGFR expression in HER2-enriched was significantly higher than those in TNBC,Luminal B and Luminal A(P＜0.01),and EGFR expression in TNBC was significantly higher than those in Luminal B and Luminal A (P＜0.01),furthermore,EGFR expression in Luminal B was significantly higher than that in Luminal A (P＜0.01).EGFR protein expression rates in ER+/PR+ subtype,ER+/PR-subtype,ER-/PR+ subtype and ER-/PR-subtype were 25.4％ (61/240),52.0％ (26/50),75.0％ (3/4),88.4％(153/173),respectively.The EGFR expression in ER-/PR-subtype was significantly higher than in ER+/PR+ subtype and ER+/PR-subtype (P＜0.01),and EGFR expression in ER+/PR-subtype was significantly higher than that in ER+/PR+ subtype (P＜0.01).EGFR protein expression rate was higher in ER-/PR-subtype than in ER-/PR+ subtype,and EGFR protein expression rate was higher in ER-/PR+ subtype than that in ER+/PR+ subtype and ER+/PR-subtype,but all of the difference were not statistically significant (P＞0.05).Conclusion EGFR protein expression is closely related to breast cancer molecular subtyping and negative hormone receptor expression,which is a potential biomarker of anti-breast cancer therapy.