Study on Weight Loss in Advanced Cancer Patients

Inclusion Criteria: * Have a primary diagnosis of unresectable or stage IV 1) non-small cell lung cancer (NSCLC), 2) pancreatic adenocarcinoma, or 3) colorectal cancer * Note: Patients do not need to have cachexia to be eligible * Plan to start first-line systemic anti-cancer therapy (chemotherapy, immunotherapy, targeted therapy, interventional clinical trial) in the next 6 weeks or has started first-line systemic therapy in the previous 6 weeks. * NOTE: Patients who received systemic anti-cancer therapy previously as part of adjuvant or neoadjuvant treatment and have since recurred are still eligible if such treatment ended \> 6 months prior to enrollment. Patients receiving concurrent radiation with systemic therapy or received local therapy alone (surgery, radiation therapy \[RT\]) prior to first line therapy remain eligible. Patients receiving maintenance treatment after first line therapy are not eligible * Have an Eastern Cooperative Oncology Group (ECOG) performance status of 0, 1 or 2 * Be able to understand, speak and read English * Be 18 years of age or older Exclusion Criteria: * Have contraindications to physical function assessments (30-second arm curl, Timed-Up-And-Go test, or 30-second chair-stand test) per the treating provider or their designee * Have any planned major surgeries within the next 3 months * Have received chemotherapy or surgery for separate primary cancer within the past 3 years other than early local staged non-melanoma skin cancer * Be pregnant