What happened, in summary

At age 73, a woman had a history of grade 3 ductal carcinoma of the left breast diagnosed in 2001. The tumor was T2N0, estrogen-receptor-negative, and HER2-negative.

She underwent left mastectomy followed by adjuvant doxorubicin and cyclophosphamide. She also received annual intravenous zoledronic acid for osteoporosis, with one infusion held when renal impairment developed. The bone-strengthening treatment was initially prescribed for fracture prevention rather than metastatic breast cancer.

Seven years later, she developed a separate cancer in the right breast. That second tumor was T2N1 and estrogen-receptor-positive, with a distinct treatment course that later included endocrine therapy, radiation, bone-targeted medicines, and management of metastatic bone disease. She was also diagnosed in 2008 with a separate non-metastatic renal cell carcinoma and underwent left nephrectomy.

The 2001 left-sided cancer and the later right-sided cancer had different receptor profiles and treatment paths. Her left-sided journey consisted of mastectomy and adjuvant chemotherapy. The later metastatic and end-of-life course followed the right-sided, hormone-receptor-positive cancer.