Gemcitabine and Erlotinib Before and After Surgery in Treating Patients With Pancreatic Cancer That Can Be Removed by Surgery

This is a single arm, non-randomized phase II study. Eligible, fully registered patients will receive preoperative chemotherapy consisting of gemcitabine plus erlotinib. Preoperative chemotherapy will be followed by exploratory laparotomy and pancreaticoduodenectomy. Patients will then receive postoperative chemotherapy consisting of gemcitabine plus erlotinib. Up to 123 patients will be accrued to this study, with the expectation that 78 patients will remain fully eligible and evaluable for the primary endpoint. The primary and secondary objectives for the study are listed below. Primary Objective: To estimate the proportion of patients alive at two years from the date of registration Secondary Objectives: 1. To determine the resection rate (defined as the fraction of patients who proceed to planned surgery with removal of primary tumor \[R0/R1\]) following induction treatment with gemcitabine plus erlotinib 2. To estimate the time to disease progression/relapse 3. To evaluate the rate of R0, R1, and R2 resections (defined as per the 6th edition of the AJCC Cancer Staging Manual) in patients treated with preoperative gemcitabine plus erlotinib chemotherapy 4. To evaluate the toxicity profile of preoperative gemcitabine plus erlotinib and the feasibility of postoperative gemcitabine plus erlotinib 5. To evaluate response rates to preoperative chemotherapy for patients treated with preoperative gemcitabine and erlotinib 6. To identify molecular predictors of pancreatic cancer response to gemcitabine combined with erlotinib 7. To identify genetic profiles of pancreatic adenocarcinoma that may be associated with response to neoadjuvant therapy After completion of postoperative chemotherapy treatment, patients are followed every 3 months for 2 years and then every 6 months for 2 years.