GI Organ Tracking Via Balloon Applicators

Inclusion Criteria:

Scheduled to receive intra-thoracic or abdominal radiation therapy. It is not required that the stomach be in the radiation field.
At least 18 years of age.
ECOG performance status ≤ 1
Ability to understand and willingness to sign an IRB approved written informed consent document (or that of legally authorized representative, if applicable).

Exclusion Criteria:

Prior trauma or surgical intervention that would alter the anatomy of the upper airs (nasogastric route), esophagus or stomach.
Previous complete or partial surgical resection of the esophagus, stomach, or duodenum.
Presence of implantable devices (e.g., automatic internal cardiac defibrillator, cardiac or gastric pacemaker).