Prevention of Pegfilgrastim-Induced Bone Pain (PIBP)

Inclusion Criteria: * Diagnosis of a non-hematologic (non-myeloid) malignancy * Scheduled to receive chemotherapy; chemotherapy may be given for adjuvant, neoadjuvant, curative, or palliative intent * Scheduled to receive the first dose of pegfilgrastim (Neulasta®) to ameliorate chemotherapy-induced neutropenia * Creatinine ≤ 1.5 times upper limit of normal * Able to understand English * More than 6 months since prior surgery on the heart Exclusion Criteria: * Pregnant or nursing * Clinical evidence of active gastrointestinal bleeding, prior gastrointestinal bleeding, or gastric or duodenal ulcers * Allergy to naproxen * Prior development of the triad of asthma, rhinitis, and nasal polyps after taking acetylsalicylic acid (aspirin) or other NSAIDs * Concurrent nonsteroidal anti-inflammatory drugs (NSAIDs), such as aspirin, ibuprofen, or any product containing naproxen (e.g., Naprosyn, EC-Naprosyn, Anaprox, Anaprox-DS, Naprosyn suspension, or Aleve), on a regular basis * Concurrent steroids on a regular basis * Concurrent prescription or non-prescription medications for preexisting chronic pain; concurrent cardioprotective doses (≤ 325 mg/day) of aspirin allowed * Concurrent therapeutic doses of warfarin