Clinical features of bilateral primary breast cancer by molecular subtypes / 中华普通外科杂志

ABSTRACT

Objective To analyze the clinicopathological features of bilateral primary breast cancer (BPBC) by molecular subtypes.Methods Clinical data of 145 BPBC patients were reviewed focusing on the clinicopathological features of different molecular subtype and the concordance of molecular subtype between first and second primary breast cancers.Results Of the first primary breast cancers ( FPBC),91 cases (62.8％ ) were Luminal A subtype,Luminal B subtype in 13 cases (9.0％ ),Human epidermal growth factor receptor 2 (HER-2) subtype in 14 cases (9.7％ ),triple negative breast cancer (TNBC) in 27 cases ( 18.6％ ).Of the second primary breast cancers ( SPBC ),Luminal A subtype was found in 93 (64.1％ ) cases,Luminal B subtype in 10(6.9％ ) cases,HER-2 subtype in 14(9.7％ ) cases and TNBC in 28( 19.3％ ) cases.Most TNBC patients were young ( age ≤ 50 ) with high frequency of grade Ⅲ in FPBC.Molecular subtypes do not vary with tumor size,clinical stage,lymph node status and pathological types ( P ＞ 0.05 ).Most FPBC of Luminal A and TNBC were concordant same subtypes in SPBC ( K ＞ 0.04 ),while Luminal B and HER-2 subtypes often had discordant phenotypes in SPBC ( K ＜ 0.04).BPBC were more likely to have concordant subtypes if the two tumors developed in short time interval.Conclusions The distribution and clinical leatures of each subtype in BPBC is similar to unilateral breast cancer.Patients whose FPBC are Luminal A or TNBC often have concordant phenotypes for their SPBC,a short time interval between two cancers also predicts concordance.