ED06.03 Pain Management

Abstract

Pain is the most common symptom in cancer patients and it is also the most common symptom in lung cancer patients. [1] The majority of patients with lung cancer present with advanced stage of the disease at diagnosis. Symptoms may result from local effects of the tumor, from regional or distant spread or from distant effects not related to metastases-paraneoplastic syndromes. Pain in these patients may be associated with depression, fatigue [2] and may affect quality of life and patients’ performance status. Early palliative care including pain management may increase their survival. [3] Pain can be classified by type of pain or according to the origin of the pain. The location or origin of the pain determines the type of pain, thoracic or extrathoracic. Pain is often multifactorial in origin and needs to be addressed in each aspect. It can be acute or chronic. Acute pain can be caused by hemorrhage into a tumor, bone pain secondary to a pathological fracture, visceral pain, ie. from acute intestinal obstruction or perforation of a viscous. Its duration is limited and predictable. Chronic pain is differentiated by its longevity. It is estimated that approximately 75% of cancer patients live with chronic pain. [4] It must be approached with dual Aim: relieving the pain as well as preventing further recurrences of pain. Physiological pain is termed nociceptive pain due to the stimulation of the sensory nociceptors located in tissues when damaged. They are somatic, visceral, neuropathic and psychogenic pains. [5] Neuropathic pain is associated with a loss of opioid receptors in sensory afferents and an increased release of glutamate in the dorsal horn. The resultant hyperexcitability causes spontaneous pain and hyperalgesia and allodynia in areas adjacent to the nerve damage. There are three main causes of pain in patients with advanced lung cancer: Skeletal metastatic disease 34%, Pancoast tumor 31%, chest wall disease 21%. [6] The World Health Organization analgesic ladder for cancer pain relief provides a stepwise approach to managing pain in cancer patients. [7] Step 1 includes paracetamol or non-steroidal anti-inflammatory drugs. Step 2- weak opioids, ie. codeine. Step 3- strong opioids, ie. morphine. Non-opioid and adjuvant treatments can be added to steps 2 and 3. Different routes of the administration of analgesics and their side effects management will be described. Their advantages and disadvantages of each route of administration will be pointed out. The need of adjuvant treatments such as tricyclic antidepressants and anticonvulsants, corticosteroids, topical analgesics, treatments of nausea, constipation, etc., are an integral part of pain management. Interventional procedures help reduce the doses of analgesics and their side effects. [8] Special mention will be about skeletal metastases and bone targeted agents such as zoledronic acid and denosumab, which have shown ability to reduce the pain and analgesic consumption in lung cancer patients. [9] Complementary therapies which help to control pain will also be mentioned.ie. Acupuncture, [10] psychological methods of care, etc. An active multidisciplinary approach is required to manage pain in patients with advanced lung cancer. Multifactorial pain is frequent and may require several different analgesics, along with general palliative care and even special interventional procedures. Patients with advanced lung cancer live longer as there are more treatment options. It is of utmost importance to preserve a good quality of life with a better performance status to enable them to receive now further available therapies.