opioids with or without olanzapine in treating patients with moderate to severe cancer pain

Conditions: Hematopoietic/Lymphoid Cancer; Pain; Unspecified Adult Solid Tumor, Protocol Specific

Summary: rationale: opioids lessen pain caused by cancer. it is not yet known whether opioids are more effective when given together with or without olanzapine in treating cancer pain. purpose: this randomized clinical trial is studying opioids to see how well they work when given together with or without olanzapine in treating patients with moderate to severe cancer pain.

objectives: * to assess the analgesic effect of olanzapine when administered in combination with opioids in patients with cancer pain. * to assess the opiod-sparing effect of olanzapine vs placebo. * to assess the effect of olanzapine on opioid adverse effects. outline: patients undergo opioid titration with a step 3 opioid to maintain a less than 4/10 level of pain (on a 0-10 numeric pain rating scale) to establish a opioid starting dose. when the pain rating increases, patients are randomized to 1 of 3 treatment arms. * arm i: patients receive oral opioid and oral placebo once daily for 4 weeks. * arm ii: patients receive oral opioid and 2.5 mg oral olanzapine once daily for 4 weeks. * arm iii: patients receive oral opioid and 5 mg oral olanzapine once daily for 4 weeks. patients undergo quality of life assessments at baseline and three times weekly by questionnaires using a scale from 0-3 and pain assessments periodically by brief pain inventory, edmonton symptom assessment scale, linear analogue scale assessments, and mini-mental state examination.

Eligibility criteria:
disease characteristics: * moderate to severe cancer pain * pain score ≥ 7/10 (0-10 numeric pain rating scale) * requires strong opioids (step 3) for pain control or are already on stable doses of step 3 opioids * opioid induced cognitive dysfunction or cognitive impairment, defined as cognitive disorder not otherwise specified according to diagnostic and statistical manual of mental disorders (dsm-iv) allowed * no nonmalignant pain * if patient has both malignant and nonmalignant pain, eligibility will be determined by the predominant site of pain patient characteristics: * life expectancy ≥ 3 months * normal renal function * not pregnant or nursing * negative pregnancy test * must have a telephone * able to complete patient questionnaires alone or with assistance * no delirium * no hepatic dysfunction * no nursing home patients * no intractable nausea or vomiting * no true allergy or intolerance to opioids * no gastrointestinal pathology that influences absorption of opioids * no drug seeking behavior or recent substance abuse history * no major depression * no respiratory compromise * no evidence of severe or uncontrolled systemic disease (e.g., unstable or uncompensated respiratory, cardiac, hepatic, or renal disease) * no evidence of any other significant clinical disorder or laboratory finding that makes it undesirable for the patient to participate in the study prior concurrent therapy: * more than 1 month since prior radiotherapy, chemotherapy, or radionuclides * more than 1 month since prior bisphosphonates * no prior surgery that influences absorption of opioids * no concurrent therapeutic procedures or treatments that influence pain * no concurrent active radiation or antineoplastic therapies * no concurrent retroviral therapies * no concurrent drugs that interfere with cyp34a, cyp1a2, or cyp2d6 * no concurrent drugs that interfere with morphine metabolism * no concurrent medications that will influence the disposition of morphine or methadone * no other concurrent antiemetics, antianxiety, or neuroleptic agents

Keywords: unspecified adult solid tumor, protocol specific hematopoietic/lymphoid cancer pain