Eligible patients will have a diagnosis of both pancreatic adenocarcinoma and cachexia defined as greater than 5% unintentional weight loss within 6 months prior to screening visit. Patients must be greater than 18 years of age; and have greater than 3 months life expectancy.

This study will observe a standard of care intervention (tube feeding) for potential benefit. Peptamen will be administered through a jejunal or a gastrojejunal feeding tube and dosing will be calculated using the Mifflin St. Jeor equation. It will be administered daily for the duration of the protocol.

In this study, we will prospectively evaluate advanced pancreatic adenocarcinoma patients with cachexia, who are receiving enteral feeding, with a peptide based diet (medical food), through a jejunal or gastrojejunal feeding tube. We plan to collect serum samples routinely and establish a cohort of patients with this clinical syndrome. Our aims are to establish the feasibility and efficacy of enteral nutrition and its relationship to meaningful clinical outcomes. Furthermore, we will assess for a correlation between cachexia, activity, and patient reported outcomes on domains of quality of life in an optional activity tracker sub-study.

Inclusion Criteria:

• Advanced or locally advanced pancreatic cancer patients (can include new or recurrent diagnosis) referred to SOCCI-CSMC for chemotherapy
• Cachexia defined as greater than 5% unexplained weight loss within 6 months prior to screening visit or consultation with medical oncologist
• Candidate for enteral feeding with Peptamen, a peptide based formula. Must have jejunal or gastrojejunal tube either previously placed or at least prior to Day 1 of study
• Age ≥ 18 years.
• ECOG performance status 0-2
• Greater than or equal to 3 month life expectancy
• Ability to understand and the willingness to sign a written informed consent
• May have received prior anti-cancer treatment, complete or partial resection of primary tumor
• Patients must be ambulatory and have access to a smart phone to participate in the activity tracker sub-study

Exclusion Criteria:

• Patients with known brain metastases should be excluded from this clinical trial because of their poor prognosis and because they often develop progressive neurologic dysfunction that would confound the evaluation of neurologic and other adverse events
• Malignant ascites requiring paracenteses
• Uncontrolled intercurrent illness including, but not limited to, ongoing or active infection, symptomatic congestive heart failure, unstable angina pectoris, cardiac arrhythmia, or psychiatric illness/social situations that would limit compliance with study requirements
• Bowel obstruction, partial or total
• Pregnancy

Pancreatic cancer patients with cachexia receiving enteral feedings by way of gastrojejunal or jejunal tube.