 PRE-OPERATIVE NEOADJUVANT CHEMOTHERAPY: Patients receive nab-paclitaxel intravenously IV over 30 minutes and gemcitabine hydrochloride IV over 30 minutes on days 1, 8, and 15. Treatment repeats every 28 days for 2 courses in the absence of disease progression or unacceptable toxicity. Beginning 3-6 weeks after completion of chemotherapy, patients undergo IG-IMRT 5 days a week for 28 fractions and receive fluorouracil IV continuously on days 1-7 for 6 weeks. 