Which of the following would be considered a cancer-related red flag warranting urgent referral?

• A. History of cancer.
• B. Age under 40 with limb pain.
• C. Mild, non-worsening pain.
• D. Pain that improves with rest.

Answer: (A)

A cancer history is a major red flag that requires urgent referral because new limb or bone pain in someone with prior cancer could signal recurrence or metastasis. Metastatic disease can spread to bone and other tissues, and early detection changes management and prognosis, so clinicians escalate evaluation promptly with imaging and oncologic assessment. The other scenarios—being under 40 with limb pain, mild, non-worsening pain, or pain that improves with rest—are more typical of benign musculoskeletal issues or overuse injuries and do not by themselves indicate cancer recurrence or metastasis.