A burgeoning clinical experience has begun to define the nature of optimal therapies for cancer pain and the outcomes that may be anticipated when these therapies are competently administered. Although the existing data are inadequate for a detailed economic analysis of diverse analgesic approaches, current information is beginning to clarify the issues and concerns that must be addressed as such analyses are attempted.
A paradigm for economic analyses of cancer pain management must include justification for the costs of optimal care, agreement about the elements that constitute this care, and recognition of the link between cancer pain and the broader clinical approach known as palliative care. This paradigm strongly supports a more specific framework for cost analysis that has been developed by the pain panel of the US Agency for Health Care Policy and Research (AHCPR) .
Justifying the Costs of Pain Management
Numerous surveys have established that chronic pain is experienced by 30% to 50% of cancer patients who are receiving active antineoplastic therapy and by 75% to 90% of those with advanced disease [2,3]. The extraordinary prevalence of this problem assures that a high aggregate cost will be incurred by the provision of optimal care to all patients. It is useful to explore the justification for these costs as a starting point for economic analyses of management strategies.
There are several compelling reasons to ensure access to qualified caregivers and a system of care that is capable of providing the best possible therapy for cancer pain. First, the costs of unrelieved pain are potentially very high. Pain is strongly associated with morbid effects on mood and other aspects of quality of life [4,5]. Severe pain produces a stress response, encourages immobility, reduces the likelihood of salutary behaviors (such as the maintenance of good nutrition), and complicates the medical evaluation and treatment of the neoplasm. Substantial costs may result from the management of pain-related complications, such as deep venous thrombosis caused by immobility, or from the need to repeat procedures or tests that could not be performed adequately due to pain.
Hospitalizations for pain control are common and extremely expensive. For example, an analysis of unscheduled admissions at the City of Hope Medical Center estimated an annual cost for uncontrolled cancer pain that exceeded $5 million . A recent Canadian survey suggested that good palliative care could lower overall costs by reducing the frequency of hospitalization .
Second, the cost of optimal pain management compares very favorably with the costs of other cancer care. Cancer treatment in the United States is strongly oriented to expensive antineoplastic therapies, many of which have never been shown to have more than marginal effects on survival. There is increasing recognition of the need to assess these therapies in terms of a broader range of potential benefits and burdens, including cost . Although comparisons remain speculative in the absence of meaningful economic data, it is likely that optimal pain management and other palliative care interventions are far less expensive than many primary antineoplastic approaches. It is difficult to justify the failure to improve symptom control on economic grounds, given these disparities.
Third, it is a moral imperative of medicine to provide comfort, if this is possible and consistent with the larger goals of care . Indeed, comfort and function may be the most important treatment objectives in a disease, like cancer, that is often incurable.
Elements of Pain Management
There is good evidence that the expert administration of simple pharmacologic approaches can provide satisfactory pain relief to at least 70% of cancer patients [2,3,10]. These simple approaches, which were originally promulgated by the Cancer Unit of the World Health Organization (WHO) , have been endorsed by many national organizations [11-13] and were recently refined in a consensus document developed by the AHCPR . Those patients who are unable to attain adequate analgesia through optimal pharmacotherapy have numerous other options, all of which are selected on the basis of clinical experience. Although the proportion of patients who could potentially benefit from the full array of pharmacologic and nonpharmacologic analgesic therapies is unknown, specialists in cancer pain generally believe it to be extremely high, probably more than 90%.
Although conventional practice settings do not routinely achieve success rates of 70% to 90% , the clinical approaches that potentially yield these outcomes can be explored to define the nature and costs of optimal cancer pain management. These approaches include a comprehensive assessment, pharmacotherapy, and alternative analgesic approaches for refractory pain (Table 1).
Assessment of Cancer Pain
The management of cancer pain relies strongly on a comprehensive assessment. The goals of this assessment include:
1. Detailed information about pain characteristics (such as onset and duration, course, intensity, location, and quality).
2. Elucidation of the etiology of the pain and its relationship to the cancer.
3. Identification of the pain syndrome and development of inferences about the pathophysiology of the pain.
4. Understanding of the impact of the pain and related symptoms on physical and psychosocial functioning.
5. Evaluation of the extent of disease and concurrent medical, psychological, and social disturbances.
In patients with active cancer, the pain assessment is likely to identify an underlying structural lesion directly related to the neoplasm. A survey of patients referred to a pain service in a major cancer hospital noted that previously unsuspected lesions were identified in 63% of patients who were comprehensively evaluated; this outcome altered the known extent of disease in virtually all patients, changed the prognosis for some, and provided an opportunity for a primary antineoplastic therapy in approximately 15% .
These data underscore the potential costs of a comprehensive pain assessment. Pain evaluation is time consuming, requires a physical examination, and commonly leads to imaging procedures that clarify the relationship between the neoplasm and the symptom. The costs of this assessment cannot be eliminated and, indeed, could potentially yield savings related to improved management of both symptoms and the underlying disease.
The need for meaningful cost analyses in this area is illustrated by the evaluation of back pain in patients with metastatic cancer. In a substantial, but ill-defined, proportion of patients, a careful clinical evaluation of this pain syndrome suggests the need for a relatively expensive procedure, magnetic resonance imaging. The purpose of this procedure is to diagnose or exclude one potential cause of back pain, epidural extension of the neoplasm, which can produce devastating neurological impairment if not treated early. Given the dire consequences of untreated epidural disease, clinicians must maintain a low threshold for imaging. Although the overall cost of this imaging is undoubtedly very high, it is likely balanced by the savings inherent in the early discovery of epidural disease in some patients. Indeed, it may be speculated that prevention of one case of paralysis may save the health care system an amount sufficient to justify, on a cost basis, many negative imaging procedures. Economic analyses of this type are lacking and are needed to assess the cost implications of cancer pain evaluation.
The Role of Primary Therapy
The first step in the management of cancer pain involves consideration of primary therapy directed against the etiology of the pain. Radiotherapy can both provide analgesia and reduce the risks associated with morbid structural pathology, such as impending fracture or epidural spinal disease . Some patients are offered chemotherapy specifically for analgesic purposes, and the decision to pursue a surgical treatment is often influenced by the potential for analgesic consequences.
The costs associated with the requirement for expert oncologic care to optimize analgesic outcomes merge with those associated with treatments to prolong life. Economic models that clarify these considerations will be complex. In some situations, it may be possible to distinguish the use of radiotherapy for curative or life-prolonging intent from its use as a primary analgesic modality. In other cases, this distinction will have little meaning. Regardless, it is important to recognize that access to competent oncologic care, particularly radiotherapy, is an element of the costs that must be borne to optimize pain management .