Revista de la Sociedad Española del Dolor
versión impresa ISSN 1134-8046
AGUILAR, J.L. et al. Pain in clinical hematology. Rev. Soc. Esp. Dolor [online]. 2010, vol.17, n.1, pp.32-50. ISSN 1134-8046.
Objective: The present review aims to provide an update on the pain management and/ or palliative care provided to patients with hematological disease, whether malignant or not. In hematology, several entities may require alleviation of pain or other distressing symptoms. It is generally acknowledged that only 5% of patients with malignant hematological disease experience pain, while this percentage ranges from 70 to 80% in other types of cancer (lung, prostate and breast, which frequently lead to bone metastases). Pain may be caused by the disease itself, due to leukemic or myelomatoid infiltration, bone destruction (75-80%), the therapies administered (15-19%), mucositis in neutropenic patients, methotrexate, thalidomide (paresthesias), bortezomib (Velcade®), imatinib (Glivec®), bone marrow transplantation, neurotoxicity of cytostatic agents (vincristine, cisplatin) and radiotherapy. Pain is unrelated to malignant disease in 3-5% of patients (muscular weakness and myalgia, decubitus ulcers, postherpetic neuralgia, diagnostic procedures). Classically, sickle cell disease, which is not a prevalent disease in Spain, is included among the benign hematological diseases that produce pain exacerbations. According to our experience, 10 years after our previous review on the topic, the percentage of hematological patients requiring specific management of "pain" (understood as "global pain" = physical, emotional, spiritual, social, occupational, familial...) can increase if, in addition to patients with pain, we also include those with unpleasant symptoms of varying severity throughout the course of their disease. The World health Organization (WHO) estimates that 9 million new cases of cancer occur each year, that there are 6.7 million annual deaths from cancer and that almost 25 million persons are still alive 3 years after diagnosis. Pain is moderate to intense in 40-50% of patients and very intense or intolerable in 25-30%. The WHO predicts that there will be 15 million new cases of cancer by 2020. Hematological cancer (leukemia, lymphoma and myeloma) is the fifth most frequent form of cancer and the second most frequent cause of death from cancer. Pain management and palliative care are based on symptom control (including pain) and the provision of appropriate emotional support to patients and their families. Material, methodology and results: We provide an update of the literature and summarize our experience in pain management and palliative care. The general features of symptoms in these patients are described, and the definition and classification of pain and the terms used in pain management are discussed. Next we focus on oncohematological pain, methods to measure this pain, and the therapeutic strategy still recommended by the WHO for its control. This strategy includes the "analgesic elevator", which increases the speed in moving up the steps of the analgesic ladder when required by the situation. The concept of opioid rotation is also discussed, as well as treatment of the most common adverse effects of opioids: constipation, nausea-vomiting, drowsiness and sedation, especially in older patients. The key to successful analgesia and symptom control lies in individually tailored analgesic regimens and the use of the oral route whenever possible (leading to greater patient comfort). In particular, we describe pain related to mucositis and sickle cell disease, as well as the methodological principles in which symptom control is based and the pharmacological therapies used to relieve pain. The distinct routes of administration of these drugs are described, with their benefits and drawbacks. Conclusions: Only 5% of patients with hematological disease experience severe pain. Oral opioid administration, according to the analgesic scale of the WHO, is the most effective, simple and efficient (cost/effectiveness) method for the management of pain in hematological disease. Conversion tables for use in opioid rotation are available. With this approach, pain can be controlled in approximately 85% of patients. Analgesic techniques with subcutaneous infusion or catheters are also excellent methods for the management of pain in these patients, but are more expensive and complex. Such techniques are generally only necessary in the remaining 15% of patients and require a normal platelet count and, in order to prevent the risk of infection, a normal granulocyte count, as well as a rigorous clinical follow-up.
Palabras clave : Pain; Hematology; Oncology; Palliative care; Symptoms.