Most patients with advanced cancer, and up to 60% of patients with any stage of the disease, experience significant pain. The World Health Organization (WHO) estimates that 25% of all cancer patients die with unrelieved pain. Although pain can be adequately in most cancer patients, it remains under-treated because of unfounded fears of opioid addiction, unavailability of analgesics from pharmacies, and cultural factors; however, it is the responsibility of healthcare professionals to address these barriers. Despite nearly 2 decades of awareness, medical oncologists continue to see poor pain management education during training, inadequate pain assessment, reluctance to prescribe opioids, and regulatory barriers. These trends are documented in every care setting, including designated cancer centers, where one-third of cancer patients continue to receive an inadequate dose of analgesics. Minority and elderly cancer patients continue to be more likely to have inadequate pain management, including administration of analgesics and palliative radiotherapy. The management of cancer-related pain is an ethical responsibility of healthcare professionals to relieve unnecessary suffering, as part of the duty to care.
Pain Symptoms: Cancer pain syndromes vary by tumor type and are related to patterns of tumor growth and metastasis. Pain may also be related to anti-neoplastic therapy. Many patients have pain caused by other co-morbid nonmalignant conditions, such as arthritis. Thorough evaluation is needed to distinguish cancer-related from non–cancer-related pains.
Elements of Management:
First and foremost, elements of cancer pain management include adequate management of symptoms to relieve suffering while undertaking a diagnostic evaluation that determines the cause of the pain. Once the cause of the pain is determined, specific interventions are selected to target it to provide durable pain relief and prevent potential cancer-related morbidity, such as pathologic fracture and spinal cord compression. Interventions to relieve cancer pain should be chosen according to the:
(1) cause of the pain
(2) patient prognosis and performance status
(3) prior therapies; and, most important
(4) the preferences of the patient in the context of overall goals of care
Ongoing care is needed to monitor the efficacy of the pain management plan relative to the evolution of other symptoms during treatment or to later disease progression. Recurrent pain or new sites of pain often are the first indications of cancer progression and should be promptly evaluated.