Evaluation of Respiratory Motion-Corrected Cone-Beam CT in Radiation Treatment of Thoracic and Abdominal Cancers

Evaluation of Respiratory Motion-Corrected Cone-Beam CT in Radiation Treatment of Thoracic and Abdominal Cancers

Tumors must be seen clearly on CT scan to be radiated completely and safely. Breathing causes tumors to move. If the tumor moves during breathing, it can look blurred on the CT scan. This makes it difficult to see on CT scan. The investigators wish to investigate whether a new computer method makes tumors less blurry and easier to see on CT scan. Cone-beam CT is a type of CT scanner attached to the radiation treatment machine that produces 3D images of the patient. Since your tumor can move because of your normal breathing, it is often blurry and difficult to see accurately in a standard cone-beam CT scan. The investigators intend to use a computer method which processes the cone-beam CT data in a way that reduces the blurring and makes the tumor easier to see.

Inclusion Criteria:

• Patients must have histologic proof of a thoracic or abdominal malignancy, confirmed at MSKCC and suitable for radiation therapy, in order to be eligible for this study. Thoracic malignancies (study group 1) include those in lung and gastro-esophageal junction. Abdominal malignancies (study group 2) include those in liver and pancreas. Patients having both thoracic and abdominal malignancies will be placed in only one of the study groups, because the limited field-of-view of the CBCT precludes imaging of both malignancies in the same scan. Patients must be older than 18 years of age
• At least part of the tumor must be visible as observed in a diagnostic or planning CT. The tumor must exhibit at least 5 mm motion from respiration as observed in the respiration-correlated CT (RCCT) at simulation. The RCCT scan must be interpretable and not exhibit excessive motion artifacts caused by irregular patient breathing.
• Patients must have Karnofsky Performance Status ≥ 70%

Exclusion Criteria:

• Mesothelioma and other tumors of the pleura
• Pregnant Women
• Allergic to iodine or intravenous contrast agent (applies only to patients with a pancreas or liver malignancy)
• Renal impairment due to the use of a contrast agent
• Patients with pacemakers and defibrillators