Comparative study on mammography between triple negative and triple positive breast cancer

Abstract

Objective To analyze the mammographic findings of triple-negative breast cancer [TNBC,which is estrogen receptor (ER) negative,progesterone receptor (PR) negative,and human epidermal growth factor receptor 2 ( HER2 ) negative ] and triple-positive breast cancer ( TPBC,which is ER positive,PR positive,and HER2 positive ),and to evaluate the relationship of immunohistochemologic receptor status and mammographic findings.Methods The immunohistochemistry results of 631 cases with breast cancers were reviewed,including 117 cases of TNBC and 44 cases of TPBC.All of the patients took mammography at initial diagnosis.We retrospectively evaluated the visibility,morphology,distribution and size of the lesion (masses and calcifications) and breast density on mammography of TNBC,and compared them with those of TPBC.The age onset and tumor sizes of TNBC and TPBC were compared by using Chi-square test and t test.Results The visibility rate of TNBC and TPBC on mammography were 88.0％(103/117) and 90.9％ (40/44),and the difference between them was insignificant ( x2 =0.055,P ＞0.05).TNBC was more frequently associated with merely a mass (56/103) than TPBC (12/40) (x2 =6.860,P＜0.01 ),and the mean diameter of the mass of TNBC [ ( 2.6 ± 1.4 ) cm ] was larger than that of TPBC [(2.0 ± 0.6) cm] (t =2.087,P ＜ 0.05). TNBC were less frequently associated with microcalcifications (37/103) than TPBC ( 24/40 ) ( x2 =7.423,P ＜ 0.01 ).Mammographic density and lesion visibility were similar between the two different immunophenotypes of breast cancers.The mean age of TNBC (52±9) was more than that of TPBC (48 ±8) (t =2.759,P ＜0.01).Infiltrating ductal carcinoma was the main pathologic type of both groups.Basal-like breast cancer accounted for 49％ (57/117 ) of TNBC while none happened in TPBC.Conclusions TNBC shows merely a mass with indistinct margins,lager size and is less associated with microcalcifications.These mammographic features might be useful in diagnosing triple negative breast cancer. Key words: Mammography; Breast neoplasms; Comparative study