Does bone metastasis cause intermittent or constant pain?

From the Guidelines

Bone metastasis typically causes constant pain that gradually worsens over time, though it can also present as intermittent pain in some cases. The pain often begins as intermittent, especially when bearing weight or moving, but frequently progresses to become constant and may be more severe at night 1. This pain occurs because cancer cells that spread to the bone release substances that stimulate nerve endings and break down bone tissue, causing both structural damage and inflammation. Some key points to consider in the management of bone metastasis include:

• The investigation and management of patients with bone metastases should be discussed within a multidisciplinary team with links to all therapeutic modalities of relevance 1
• External beam radiation therapy (EBRT) remains the treatment of choice for localized moderate to severe bone pain due to bone metastases 1
• Bone-targeting agents like bisphosphonates or denosumab are recommended for patients with bone metastases, whether they are symptomatic or not 1 The nature of the pain depends on several factors including the location of the metastasis, the type of primary cancer, and the extent of bone involvement. Some patients experience breakthrough pain, which is a temporary flare of severe pain that occurs despite otherwise controlled background pain. Treatment typically involves a multimodal approach including analgesics (from NSAIDs to opioids), bone-targeting agents like bisphosphonates or denosumab, radiation therapy, and in some cases surgery to stabilize weakened bones. Early intervention is crucial as effective pain management can significantly improve quality of life for patients with bone metastases.

From the Research

Bone Metastasis Pain Characteristics

• The pain associated with bone metastasis can be intermittent or constant, depending on the individual case and the underlying mechanisms involved 2, 3.
• The pain is thought to be distinct from neuropathic or inflammatory pain and is caused by a complex pathophysiologic process between host and tumor cells 2.
• The process involves cellular invasion, migration, adhesion, and stimulation of osteoclastic and osteoblastic activity, leading to bone destruction and pain 2.

Pain Management Strategies

• Various treatment modalities have been tried and tested to improve pain management, including non-steroidal anti-inflammatory drugs (NSAIDs), opioids, bisphosphonates, and radiotherapy 4, 5, 6.
• Bisphosphonates have shown an analgesic effect in some studies and are considered standard care for the reduction of skeletal events associated with bone metastases 5.
• The management goal of cancer pain due to bone metastasis is not only to achieve pain relief but also to prevent pain progression and skeletal-related events (SREs) 6.

Pain Patterns and Mechanisms

• Cancer pain due to bone metastasis can be crippling and a chronic state that causes sarcopenia 6.
• The mechanism of pain due to bone metastasis is complicated and involves various interactions among tumor cells, bone cells, activated inflammatory cells, and bone-innervating neurons 6.
• It is essential to diagnose whether the pain is based on background pain or breakthrough pain due to bone metastasis to achieve optimal management 6.