MSRA-0881

A 72-year-old man with metastatic breast cancer presents to surgery with his wife. He has known bone metastases in his pelvis and ribs, but his pain is not adequately managed with paracetamol, diclofenac, and MST 30 mg bd. His wife reports that he is using 10mg of oral morphine solution approximately 6-7 times a day for breakthrough pain. The hospice palliative care team attempted to use a bisphosphonate, but it resulted in persistent myalgia and arthralgia. What is the next appropriate step?