Gemcitabine and Celecoxib in Treating Patients With Metastatic Pancreatic Cancer

DISEASE CHARACTERISTICS: Histologically or cytologically confirmed metastatic pancreatic cancer Radiographic evidence of disease No known brain metastases PATIENT CHARACTERISTICS: Age Any age Performance status ECOG 0-2 OR Karnofsky 60-100% Life expectancy Not specified Hematopoietic WBC at least 3,000/mm^3 Absolute neutrophil count at least 1,500/mm^3 Platelet count at least 100,000/mm^3 Hepatic Bilirubin no greater than 1.5 times upper limit of normal (ULN) AST/ALT no greater than 2.5 times ULN Renal Creatinine normal OR Creatinine clearance at least 60 mL/min Cardiovascular No symptomatic congestive heart failure No unstable angina pectoris No cardiac arrhythmia Gastrointestinal No history of peptic ulcer disease No gastrointestinal bleeding within the past 3 months Other Not pregnant or nursing Negative pregnancy test Fertile patients must use effective contraception No prior allergic reactions to compounds of similar chemical or biological composition to study drugs or to sulfonamides No prior allergic reaction, asthma, or urticaria after taking aspirin or NSAIDs No ongoing or active infection No other uncontrolled illness No psychiatric illness or social situation that would preclude study compliance No other malignancy within the past 5 years except basal cell skin cancer or carcinoma in situ of the cervix PRIOR CONCURRENT THERAPY: Biologic therapy Not specified Chemotherapy No prior chemotherapy for metastatic pancreatic cancer More than 6 months since prior neoadjuvant or adjuvant chemoradiotherapy (including gemcitabine) for pancreatic cancer Endocrine therapy Not specified Radiotherapy See Chemotherapy More than 6 months since prior radiotherapy Surgery Not specified Other More than 30 days since prior investigational agents No other concurrent investigational or commercial agents or therapies for the malignancy No other concurrent nonsteroidal anti-inflammatory drugs (NSAIDs) No other concurrent cyclo-oxygenase-2 (COX-2) inhibitors (e.g., rofecoxib) Concurrent acetaminophen-containing medications or low-dose aspirin (up to 325 mg/day) for cardiac prophylaxis allowed