伴管状成分的乳腺浸润性小叶癌11例临床病理分析OA

Objective To investigate the clinicopathological features and immunophenotypic characteristics of in-vasive lobular carcinoma(ILC)of the breast with tubular components.Methods The clinicopathological data of 11 cases of ILC with tubular components were retrospectively analyzed.Immunohistochemical staining was used to detect the expression of ER,PR,HER2,Ki67,E-cadherin,p120,β-catenin,CK5/6,and p63 in the cancer tissues,re-view relevant literature and analyze its relationship with clinical pathological characteristics.Results The mean age of the patients was 47.3 years(ranging from 35 to 66 years);most of the tumors were located in the left side(8/11)and the upper inner quadrant(5/11);the mean maximum diameter of the tumors was 29.4 mm(ranging from 19.0 to 70.0 mm);lymph node metastasis was common(6/11).Microscopically,small and uniform tumor cells were ar-ranged in single-file linear/cord-like structures,mixed with varying amounts of tubular structures.The tubular struc-tures and single-file linear/cord-like structures were intermingled,showed invasive growth in the fibrous stroma and surrounding adipose tissue.Among them,10 cases were accompanied by lobular carcinoma in situ components(10/11).Immunohistochemistry showed that ER and PR were both positive(11/11,100%);HER2 was positive in 1 case,negative in 9 cases,and 1 case showed IHC 2+without FISH detection;the Ki67 proliferation index ranged from 10%to 40%;no expression of CK5/6 or p63 was observed in any case.In the tubular structures,tumor cells were negative for E-cadherin(0/11),showed membranous positivity for p120(7/11),and exhibited membranous posi-tivity for β-catenin(4/4);in the single-file linear/cord-like structures,tumor cells were negative for E-cadherin(0/11),showed cytoplasmic positivity for p120(11/11),and were negative for membranous β-catenin(0/4).Conclu-sion ILC with tubular components is rare in clinical practice,immunohistochemically,the tubular components lack membranous E-cadherin expression but mostly retain membranous expression of p120 and β-catenin.It should be dif-ferentiated from tubular carcinoma,tubulolobular carcinoma,and mixed invasive ductal and lobular carcinoma.