Medicine A 74-year-old woman has metastatic bone disease on x-ray. Which of the following mediators is least likely to be involved? A interleukin-6 (IL-6) B ectopic parathyroid hormone (PTH) C tumor necrosis factor (TNF) D interleukin-1 (IL-1) 💡 Explanation A 74-year-old woman has metastatic bone disease on x-ray. Which of the following mediators is least likely to be involved? ✓ Correct Answer: B. ectopic parathyroid hormone (PTH)