An invasive carcinoma formed of irregular groups of large malignant cells exhibiting focal ductal differentiation. Anaplasia and mitosis are moderate and stromal fibrosis is mild to moderate. Focal DCIS of intermediate grade is noted.
Immunostaining was done with appropriate positive and negative controls and revealed:
Estrogen receptor: positive strong nuclear reaction in 80% of tumor cells, Allred score 8/8.
Progesterone receptor: positive strong nuclear reaction in 30% of tumor cells, Allred score 6/8.
HER2/neu: negative score 0.
Ki-67 labeling index about 25%.
Referred paraffin block for immunostaining of breast tru- cut biopsy diagnosed as breast cancer.
One referred paraffin block.
Breast mass, core biopsy, referred slide for review and immunostaining: