Pain Management for Ovarian Cancer Pain
Strong opioids, particularly oral morphine, are the cornerstone of treatment for moderate to severe ovarian cancer pain, following the WHO analgesic ladder approach from non-opioids to strong opioids based on pain severity. 1
Assessment of Pain
- Assess pain severity using patient self-report tools:
- Visual Analogue Scales (VAS)
- Numerical Rating Scales (NRS)
- Verbal Rating Scales (VRS)
- Determine pain characteristics:
- Location and radiation pattern
- Intensity (at rest and with movement)
- Timing (onset, duration, persistent or intermittent)
- Quality (somatic, visceral, or neuropathic components)
WHO Analgesic Ladder for Ovarian Cancer Pain
Step 1: Mild Pain (WHO Level I)
- Non-opioid analgesics:
- Acetaminophen/paracetamol: 500-1000 mg every 4-6 hours (maximum 4-6g daily) 1
- NSAIDs (with gastroprotection for prolonged use):
- Ibuprofen: 200-600 mg every 6-8 hours (maximum 2400 mg daily)
- Naproxen: 250-500 mg every 8-12 hours (maximum 1250 mg daily)
Step 2: Moderate Pain (WHO Level II)
- Weak opioids combined with non-opioids:
- Tramadol: 50-100 mg every 4-6 hours (maximum 400 mg daily) 1
- Dihydrocodeine: 60-120 mg modified release tablets (maximum 240 mg daily)
- Alternative: Low doses of strong opioids (morphine or oxycodone)
Step 3: Severe Pain (WHO Level III)
- Strong opioids:
- Morphine sulfate oral: Starting dose 20-40 mg daily, titrated as needed (no upper limit) 1
- Oxycodone oral: Starting dose 20 mg daily
- Fentanyl transdermal: Starting dose 25 μg/h (for stable pain)
- Hydromorphone: Alternative to morphine with similar efficacy profile
Dosing and Administration Principles
- Titrate opioid doses to effect as rapidly as possible
- Provide around-the-clock dosing for persistent pain
- Include "breakthrough" doses (at least 10% of total daily dose)
- If more than four breakthrough doses are needed daily, increase baseline opioid treatment 1
- For oral morphine, if given parenterally, the equivalent dose is 1/3 of the oral medication 1
Management of Specific Pain Types
Neuropathic Pain Components
- Add co-analgesics to opioid therapy:
Pain with Inflammatory Component
- Trial of NSAIDs or glucocorticoids 1
Managing Opioid Side Effects
- Constipation: Prophylactic laxatives should be prescribed with all opioids
- Nausea/vomiting: Anti-emetics, particularly during initiation
- Drowsiness/cognitive impairment: May improve after 3-5 days; consider dose reduction or opioid rotation
- For refractory side effects: Consider opioid rotation or alternative approaches (nerve block, radiotherapy)
Additional Interventions
- Radiotherapy: Particularly effective for bone metastases or tumors compressing neural structures 1
- Surgical interventions: May be necessary for pain caused by impending fractures or obstruction of hollow organs 1
- For refractory pain: Consider referral to pain specialist for interventional approaches
Common Pitfalls to Avoid
- Undertreatment of pain due to fear of opioid side effects
- Failure to address neuropathic components with appropriate co-analgesics
- Inadequate management of opioid-induced side effects
- Insufficient breakthrough pain coverage
- Research shows that only 54% of women with ovarian cancer pain were given high-intensity medication near death, indicating room for improvement 2
Special Considerations for Elderly Patients
- Older women (≥70 years) are less likely to receive appropriate high-intensity pain medication 2
- Start with lower doses but do not underdose based on age alone
- Monitor more closely for side effects
By following this structured approach to pain management in ovarian cancer, most patients can achieve satisfactory pain relief and maintain quality of life throughout their disease course.