Understanding the Implications of the Breast Cancer Pathology Report: A Case Study

Case Study A.K. is a 50-year-old Caucasian female who was recently diagnosed with breast cancer and is presenting for an opinion regarding adjuvant therapy following a right segmental mastectomy and sentinel lymph node biopsy. The advanced practitioner (AP) in the outpatient oncology treatment center will be expected to participate in the discussion regarding the patient's care plan. In her review of the final pathology, the AP notes that the breast tumor is infiltrating ductal carcinoma, the most common type of invasive breast cancer. It starts in the cells that line the milk ducts in the breast, grows outside the ducts, and often spreads to the lymph nodes. Infiltrating ductal carcinoma represents 65% to 85% of all breast cancer cases (College of American Pathologists, 2011). The breast tumor measures 1.2 × 0.9 × 1.0 cm(3) (T1), is estrogen receptor positive with an H score of 280, is progesterone receptor negative with an H score of 0, and is HER2 equivocal 2+ by immunohistochemistry with a fluorescence in situ hybridization ratio of 1.9 with a copy number of 5. The Ki-67 proliferation rate is 60%, and the nuclear grade is 2/3, with a Nottingham score of 5/9. The surgical margins from the segmental mastectomy are clear by 0.4 mm. There is lymphovascular invasion present. Of two sentinel lymph nodes, none is positive (N0). There has been no workup for metastatic disease. Additionally, the AP notes that the patient is premenopausal and that A.K.'s family history is positive for a maternal aunt diagnosed with a stage I breast cancer at age 75. What is the recommended plan of care for A.K.?