This case study evaluated decision coaching with a breast cancer survivor considering continuing extended endocrine therapy from eight years to 10 years. The survivor, aged 58 years and who completed surgery and chemotherapy eight years ago, was concerned about side effects of endocrine therapy. Decision coaching based on the Ottawa Decision Support Framework involved an oncology nurse using the Ottawa Personal Decision Guide. Compared to baseline (2 out of 4), decisional comfort improved (3 out of 4) post decision coaching. The survivor felt more certain, but wanted further advice from her oncologist. She was leaning toward discontinuing endocrine therapy given she valued quality of life over a small risk of recurrence. Audio-recording analysis using the Decision Support Analysis Tool revealed high decision coaching quality (10/10). Breast cancer survivors facing preference-sensitive decisions about extended endocrine therapy could be supported with decision coaching by oncology nurses to ensure informed values-based decisions.