Aprepitant in Preventing Nausea and Vomiting in Patients Undergoing Chemotherapy and Radiation Therapy for Pancreatic Cancer

PRIMARY OBJECTIVES: I. Discern the gastrointestinal toxicities associated with 5-FU (fluorouracil)/Gemcitabine (gemcitabine hydrochloride) chemotherapy when combined with upper abdominal radiation therapy. II. Determine if the addition of prophylactic Aprepitant/5HT-3/Dexamethasone therapy to standard chemoradiation for patients with pancreatic cancer results in less nausea and vomiting when compared to historical controls. SECONDARY OBJECTIVES: I. To determine the impact of prophylactic Aprepitant/5HT-3/Dexamethasone therapy on the impact of emesis on daily living, as measured using the MASCC Antiemesis (MAT) tool. OUTLINE: CHEMORADIOTHERAPY: Patients undergo radiation therapy once daily on days 1-5 for 5.5 weeks. Patients also receive gemcitabine hydrochloride intravenously (IV) over 30 minutes once weekly and either fluorouracil IV continuously or capecitabine orally (PO) twice daily on days 1-5. PROPHYLACTIC THERAPY: Beginning 1 hour before chemoradiotherapy, patients receive aprepitant PO on days 1-3. Treatment repeats every 7 days for 5.5 weeks in the absence of disease progression or unacceptable toxicity. CONSOLIDATION CHEMOTHERAPY: Two to four weeks after completion of chemoradiotherapy and prophylactic therapy, patients without disease progression or a declining performance status receive gemcitabine hydrochloride IV over 30 minutes on days 1 and 8. Treatment repeats every 21 days for 2 courses in the absence of disease progression or unacceptable toxicity. After completion of study treatment, patients are followed periodically.