What are the available drugs for relieving bone cancer pain?

Bone cancer pain is a chronic pain with a unique and complex mechanism. It is related to neuropathic pain and inflammatory pain. Severe pain is extremely detrimental to the recovery of bone cancer patients and can be relieved by analgesic drugs.

1. Opioids

Opioids are a type of analgesic commonly used in clinical practice and are the basis for analgesic treatment of bone cancer. They mainly include codeine, dihydrocodeine, hydromorphone, oxycodone, methadone, morphine, fentanyl, pethidine, etc. However, the therapeutic dose of opioids is large, and long-term use can cause side effects such as drowsiness, constipation, tolerance, and addiction.

2. Nonsteroidal anti-inflammatory drugs

The new cyclooxygenase-2 (COX-2) specific inhibitor has anti-tumor and anti-angiogenic effects. In the animal model of bone cancer pain, short-term use of this drug can slightly relieve severe bone pain, and long-term use can also reduce the destructive effects of tumor tissue and osteoclasts.

3. Bisphosphonates

Bisphosphonates were originally used to treat hypercalcemia caused by malignant tumors. These drugs can directly inhibit osteoclast activity and increase the pH value of the local microenvironment of tumor bone, thereby avoiding the activation of acid-sensitive ion channels. When analgesics and radiotherapy are ineffective in treating bone cancer pain, bisphosphonates can be considered.

4. Osteoprotegerin (OPG)

Osteoprotegerin is a drug under development that binds and blocks RANK-L. Normally, RANK-L binds to CSF-1, stimulating the formation of osteoclasts and the activation of mature osteoclasts. OPG inhibits the activation of osteoclasts by RANK-L, thereby inhibiting bone destruction. It reduces the pain that occurs as a result, but cannot completely eliminate pain behavior and neurochemical changes.