Approaches to Pain Management and Breast Cancer John Liszka-Hackzell, MD, PhD University of Arizona Anesthesiology and Pain Medicine

Educational Objectives 1- Discuss the etiology of pain in breast cancer survivors 2- Describe the multidisciplinary approach to pain management assessment and treatment 3- Outline the appropriate use of pain evaluation tools

Reasons Why Breast Cancer Patients May Have Pain Acute postoperative pain Chronic pain Neuropathic / Phantom Breast Pain Bone pain / Metastatic Cancer

Surgical Procedures for Breast Cancer Radical Mastectomy (breast, skin, pectoralis, lymph nodes) Modified radical Mastectomy (pectoralis left intact) Lumpectomy with/without axillary nodes. Lumpectomy with Sentinel node biopsy

Surgical Procedures for Breast Cancer

Choice of Surgical Procedure or Technique May Influence the Occurrence of Chronic Pain Not shown that breast-conserving treatment vs. modified radical mastectomy decreases risk of chronic pain Evidence of more chronic pain following breast-conserving surgery and axillary node dissection (Wallace et al, Pain 1996)

Choice of Surgical Procedure or Technique May Influence the Occurrence of Chronic Pain Increased risk of chronic pain after breast-conserving procedure may be related to increased use of chemo/radiation Women who have breast prosthesis may have an increased incidence of chronic pain

Breast Cancer Surgery – Innervation Third through sixth Intercostal nerves Lateral cutaneous branch of T2 (ICB) – upper, medial portion of the arm Lateral and anterior branches – anterior chest, upper back T3 innervates the axilla, anterior and posterior torso T4 and below innervates the torso. Nipple is primarily T4

Acute Post-Operative Pain Following Breast Surgery Relationship between intensity of acute post-operative pain and Chronic post-treatment pain (Tasmuth et al, Acta Oncol, 1997). Severity of acute postoperative pain is the best predictor of chronic pain in Breast Cancer

Increased Postoperative Pain May Be Related to: Unrecognized preoperative neuropathic pain Poor postoperative pain management Pre-existing depression/anxiety Surgical technique (nerve sparing procedures) Postoperative complications (infection / bleeding) Pre-existing chronic pain

Regional anesthesia techniques in combination with general anesthesia may decrease the incidence of long-term pain Thoracic epidural Paravertebral block

Pre-emptive Pain Management Postoperative Pain and Pre-emptive Pain Management Evidence that effective preoperative and intraoperative pain management reduces postoperative pain Pre-emptive pain management may reduce risk of chronic pain

Chronic Pain Following Breast Surgery Risk Factors Age? <35 worse prognosis in general Chemo, Radiation – not associated with Phantom breast pain, but other chronic pains Chronic Pain possibly greater in patients with pre-existing anxiety/depression (Tasmuth et al, Pain, 1996)

Chronic Pain Following Breast Surgery May be seen in up to 50% of mastectomy patients “Postmastectomy pain syndrome” has four components: 1) Phantom breast pain 2) ICB neuralgia 3) Neuroma pain (scar pain) 4) Other nerve injury pains (Jung et al, Pain, 2003)

Intercostobrachial Neuralgia - Arises from the lateral cutaneous branch of the second intercostal nerve Occurs more frequently with axillary node dissection (Jung et al, Pain, 2003) Technically difficult to preserve the nerve Neuropathic pain Involves axilla and medial upper arm Neuroma formation (macro/micro)

Chronic Pain Following Breast Cancer Surgery Sensory abnormalities in the intercostobrachial nerve distribution in 60-80% of women following breast cancer surgery (breast conserving vs. radical) 25% of these women will develop intercostobrachial neuralgia (Maunsell et al, Can J Surg, 1993)

Other Nerve Injury Pains Medial and Lateral Pectoral (maj/min pectoral) Long Thoracic (post shoulder/scapula, winged scapula) Thoracodorsal (latissimus) Usually spared

Distribution / Description Chronic Pain Distribution / Description Nociceptive – injury to ligament, muscle etc. Neuropathic. Originates in the nervous system Arm, neck, shoulder, axilla, chest wall or breast “continuation of acute pain” Paresthesia, Dysesthesia, Allodynia, Hyperalgesia

Chronic Pain Neuropathic Pain Paresthesia: a sensation of tingling, pricking or numbness Dysesthesia: a spontaneous or evoked unpleasant abnormal sensation Allodynia: a painful response to a usually non-painful stimulus Hyperalgesia: an increased sensititivity to pain

Chronic Pain Phantom Breast Pain and Neuropathic Pain Neuropathic pain. Damage to peripheral nerve “Regeneration” Neuroma formation Spontaneous firing Often pain is sharp, shooting and burning

Chronic Pain Phantom Breast Pain and Neuropathic Pain - Phantom pain. Not referred, but perceived - Different from Phantom sensation - Sharp, often stabbing pain - Similar to neuropathic pain - Develops weeks to months after procedure May be associated with neuroma formation

Phantom Pain - Mechanisms Not well understood Peripheral changes. Ectopic discharges from peripheral and central neuron, sympatheric activation and loss of noiception Cortical re-mapping: pre-existing pain creates a cortical pain memory Re- organization in somatosensory cortex following amputation (Flor et at, Pain Clin Update, 2000)

Chronic Pain and Breast Cancer Postoperative radiation is a risk factor for chronic arm and breast pain Correlation between axillary radiation and arm pain (Keramopoulos et al, Oncology, 1993) Plexus injuries

Chronic Pain – Prognosis Typically decreasing over the first year 31% at 1-2 years to 20% at 4 years (Ivens et al Br J Cancer, 1992) Chronic nociceptive pain better prognosis than neuropathic Neuropathic pain / Phantom breast pain are more chronic and problematic Association with depression/anxiety

Bone Pain / Metastatic Disease Results in anemia, risk of infection, pain, fractures decreased mobility Difficult to fully control (Mercadante, Pain, 1997) May be osteolytic or osteoblastic Osteoblastic tumors may provide more mechanical stability

Acute Post-operative Pain Management of Acute Post-operative Pain Pre-emptive analgesia (block, adjuvants) may decrease risk of chronic pain Standard opioids Postoperative PCA Consider appropriate regional anesthesia for postoperative pain

Management of Chronic Pain Neuropathic Pain Multidisciplinary approach Physical therapy Occupational therapy Behavioral / Pain management Acupuncture / Chiropractic Medical Management

Management of Chronic - Neuropathic Pain

Management of Chronic - Neuropathic Pain

Management of Chronic - Neuropathic Pain

Neuropathic Pain Adjuvant Medications Lyrica (Pregabalin) Works on Ca channels Approved for DPN, PHN, Fibromyalgia Side effects: Drowsiness, Sedation, Blurred vision 300-600 mg/day (bid-tid)

Management of Chronic Pain/ Neuropathic Pain

Management of Bone Pain Opiods may attenuate bone pain Biphosphonates may be helpful, however no data suggests effect on long-term survival (Fulfaro et al, Pain, 2001) COX-2 inhibitors prevents inflammatory response, bone resorption and may reduce tumor burden

Conclusion Chronic pain seen in many patients (Nociceptive vs. Neuropathic) Surgical technique Good peri-operative pain control Multidisciplinary management Multiple options for medical management