Inclusion Criteria for lung cancer subjects:
* Eligible patients will be those harboring locally advanced clinical stage I-III NSCLC who are not eligible for surgical resection, or those with stage IIIa NSCLC who are deemed candidates for multi-modality therapy, i.e. concurrent chemotherapy and radiation followed by pulmonary resection.
* Age greater than 18 years
* Have the ability to give written informed consent.
* No tobacco use within the prior 6 months.
Inclusion Criteria for pancreatic cancer subjects:
* Age ≥ 18 years.
* Life expectancy of greater than 3 months.
* Ability to understand and the willingness to sign a written informed consent document.
* Histologically or cytologically confirmed diagnosis of PDAC.
* Tumor should be confirmed with imaging based on the standard-of-care baseline abdominal CT performed within 1 month before study visit 1.
* Core samples for initial diagnosis must be available at the Department of Pathology at Massachusetts General Hospital.
* Participants with a prior or concurrent malignancy whose natural history or treatment does not have the potential to interfere with the safety or efficacy assessment of the investigational imaging and standard treatment regimen are eligible for this trial.
* Scheduled study visit 1 within 1 month prior to starting neoadjuvant chemoradiotherapy (CRT)
* Subjects undergo neoadjuvant chemotherapy followed by radiotherapy (CRT) as part of their standard clinical care and based on institutional standards.
* Scheduled surgical pancreas resection within 1 month after post-CRT study visit.
* Subjects are required to undergo pre-surgical CT of abdomen within 1 month after completion of standard neoadjuvant CRT as part of routine clinical work-up.
Exclusion Criteria for lung cancer subjects:
* Electrical implants such as cardiac pacemaker or perfusion pump
* Ferromagnetic implants such as aneurysm clips, surgical clips, prostheses, artificial hearts, valves with steel parts, metal fragments, shrapnel, metallic tattoos anywhere on the body, tattoos near the eye, or steel implants ferromagnetic objects such as jewelry or metal clips in clothing;
* Pregnant or breastfeeding (a negative quantitative serum hCG pregnancy test is required for females having child-bearing potential before the subject can participate);
* Claustrophobic reactions;
* Research-related radiation exposure exceeds current Radiology Department guidelines (i.e. 50 mSv in the prior 12 months);
* Unable to lie comfortably on a bed inside the MR-PET;
* Body weight of \> 300 lbs (weight limit of the MRI table);
* Determined by the investigator(s) to be clinically unsuitable for the study (e.g. based on screening visit and/or during study procedures);
* Known history of pulmonary disease (Except lung cancer or smoking related lung disease,)
* Pneumonia or other acute respiratory illness within 6 weeks of study entry, pneumonia defined with elevated WBC, fever, infiltrate on CXR and need for antibiotics
Exclusion Criteria for pancreatic cancer subjects:
* History of radiotherapy to the upper abdomen in the past.
* History of reaction to MRI contrast (Gadoterate meglumine)
* Clinical or imaging diagnosis of acute pancreatitis within 6 weeks prior to study visit
* Participants with uncontrolled intercurrent illness or if determined by the investigator(s) to be clinically unsuitable for the study (e.g. based on screening and/or during study).
* Participants with psychiatric illness/social situations that would limit compliance with study requirements.
* Electrical implants such as cardiac pacemaker or perfusion pump;
* Ferromagnetic implants such as aneurysm clips, surgical clips, prostheses, artificial hearts, valves with steel parts, metal fragments, shrapnel, metallic tattoos anywhere on the body, tattoos near the eye, or steel implants ferromagnetic objects such as jewelry or metal clips in clothing;
* eGFR of less than 30 mL/min/1.73 m2 within the past 90 days;
* Pregnant or breastfeeding (a negative quantitative serum hCG pregnancy test is required for females having child-bearing potential at each PET/MRI study visit;
* Claustrophobic reactions;
* Research-related radiation exposure exceeds current Radiology Department guidelines (i.e. 50 mSv in the prior 12 months);
* Unable to lie comfortably on a bed inside the MR-PET;
* BMI \> 33 (limit of the PET-MRI table)
