Assessing How Normal Variations in CT Scanning Affects Its Interpretation

Study Overview
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Brief Summary
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The purpose of the study is to see how measurements of tumor differences vary with slight changes in CT scan parameters. Reproducible radiomic features can be extracted for abdominal tumors, and specifically colorectal liver metastases, imaged with clinical CT scanners even in the setting of variable scan parameters and variable contrast timing. Participants will be consented to undergo an additional CT of their abdomen.

Official Title
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Stability of Radiomic Features for Abdominal Tumors on Contrast Enhanced CT

Conditions
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Colorectal Cancer Metastatic

Intervention / Treatment
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* Diagnostic Test: CT scan


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Patients ≥ 18 years of age on the day of signed informed consent Patients scheduled and approved for contrast enhanced CT that includes imaging of the abdomen and pelvis following the Department of Radiology standard of care protocol as per local institutional guidelines Patients with measurable colorectal liver metastases on prior imaging, with at least one tumor greater than 2.0 cm in axial maximal diameter Exclusion Criteria: Patient who is pregnant and/or lactating Patient scheduled for CT that includes the abdomen with a multiphasic contrast enhanced protocol (e.g. Triple Phase or Quadruple Phase Liver CT) Patient who require reduced intravenous contrast dose based on the Department of Radiology contrast policy as per local institutional guidelines Any other medical condition, including mental illness or substance abuse, deemed by the Investigator to be likely to interfere with a patient's ability to sign informed consent, cooperate and participate in the study, or follow up procedures

Ages Eligible for Study
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Minimum Age: 18 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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No

Study Plan
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How is the study designed?
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Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Cohort 1<br>-15 second time gap between routine abdominal CT and add on CT, Noise Index of 12 | Diagnostic Test: CT scan<br>* Patients with colorectal liver metastases scheduled for abdominopelvic CECT will be consented to undergo an additional CT of their abdomen (termed add-on CT) within 15 seconds, before or after, their clinical portal venous phase CT (PV CT), which is performed at a fixed delay of 80 seconds at our institution.<br>|
| Cohort 2<br>-15 second time gap between routine abdominal CT and add on CT, Noise Index of 14 | Diagnostic Test: CT scan<br>* Patients with colorectal liver metastases scheduled for abdominopelvic CECT will be consented to undergo an additional CT of their abdomen (termed add-on CT) within 15 seconds, before or after, their clinical portal venous phase CT (PV CT), which is performed at a fixed delay of 80 seconds at our institution.<br>|
| Cohort 3<br>-15 second time gap between routine abdominal CT and add on CT, Noise Index of 16 | Diagnostic Test: CT scan<br>* Patients with colorectal liver metastases scheduled for abdominopelvic CECT will be consented to undergo an additional CT of their abdomen (termed add-on CT) within 15 seconds, before or after, their clinical portal venous phase CT (PV CT), which is performed at a fixed delay of 80 seconds at our institution.<br>|
| Cohort 4<br>-10 second time gap between routine abdominal CT and add on CT, Noise index 12 | Diagnostic Test: CT scan<br>* Patients with colorectal liver metastases scheduled for abdominopelvic CECT will be consented to undergo an additional CT of their abdomen (termed add-on CT) within 15 seconds, before or after, their clinical portal venous phase CT (PV CT), which is performed at a fixed delay of 80 seconds at our institution.<br>|
| Cohort 5<br>-10 second time gap between routine abdominal CT and add on CT, Noise index 14 | Diagnostic Test: CT scan<br>* Patients with colorectal liver metastases scheduled for abdominopelvic CECT will be consented to undergo an additional CT of their abdomen (termed add-on CT) within 15 seconds, before or after, their clinical portal venous phase CT (PV CT), which is performed at a fixed delay of 80 seconds at our institution.<br>|
| Cohort 6<br>-10 second time gap between routine abdominal CT and add on CT, Noise index 16 | Diagnostic Test: CT scan<br>* Patients with colorectal liver metastases scheduled for abdominopelvic CECT will be consented to undergo an additional CT of their abdomen (termed add-on CT) within 15 seconds, before or after, their clinical portal venous phase CT (PV CT), which is performed at a fixed delay of 80 seconds at our institution.<br>|
| Cohort 7<br>- 5 second time gap between routine abdominal CT and add on CT, Noise index 12 | Diagnostic Test: CT scan<br>* Patients with colorectal liver metastases scheduled for abdominopelvic CECT will be consented to undergo an additional CT of their abdomen (termed add-on CT) within 15 seconds, before or after, their clinical portal venous phase CT (PV CT), which is performed at a fixed delay of 80 seconds at our institution.<br>|
| Cohort 8<br>- 5 second time gap between routine abdominal CT and add on CT, Noise index 14 | Diagnostic Test: CT scan<br>* Patients with colorectal liver metastases scheduled for abdominopelvic CECT will be consented to undergo an additional CT of their abdomen (termed add-on CT) within 15 seconds, before or after, their clinical portal venous phase CT (PV CT), which is performed at a fixed delay of 80 seconds at our institution.<br>|
| Cohort 9<br>- 5 second time gap between routine abdominal CT and add on CT, Noise index 16 | Diagnostic Test: CT scan<br>* Patients with colorectal liver metastases scheduled for abdominopelvic CECT will be consented to undergo an additional CT of their abdomen (termed add-on CT) within 15 seconds, before or after, their clinical portal venous phase CT (PV CT), which is performed at a fixed delay of 80 seconds at our institution.<br>|
| Cohort 10<br>+ 5 second time gap between routine abdominal CT and add on CT, Noise index 12 | Diagnostic Test: CT scan<br>* Patients with colorectal liver metastases scheduled for abdominopelvic CECT will be consented to undergo an additional CT of their abdomen (termed add-on CT) within 15 seconds, before or after, their clinical portal venous phase CT (PV CT), which is performed at a fixed delay of 80 seconds at our institution.<br>|
| Cohort 11<br>+ 5 second time gap between routine abdominal CT and add on CT, Noise index 14 | Diagnostic Test: CT scan<br>* Patients with colorectal liver metastases scheduled for abdominopelvic CECT will be consented to undergo an additional CT of their abdomen (termed add-on CT) within 15 seconds, before or after, their clinical portal venous phase CT (PV CT), which is performed at a fixed delay of 80 seconds at our institution.<br>|
| Cohort 12<br>+ 5 second time gap between routine abdominal CT and add on CT, Noise index 16 | Diagnostic Test: CT scan<br>* Patients with colorectal liver metastases scheduled for abdominopelvic CECT will be consented to undergo an additional CT of their abdomen (termed add-on CT) within 15 seconds, before or after, their clinical portal venous phase CT (PV CT), which is performed at a fixed delay of 80 seconds at our institution.<br>|
| Cohort 13<br>+ 10 second time gap between routine abdominal CT and add on CT, Noise index 12 | Diagnostic Test: CT scan<br>* Patients with colorectal liver metastases scheduled for abdominopelvic CECT will be consented to undergo an additional CT of their abdomen (termed add-on CT) within 15 seconds, before or after, their clinical portal venous phase CT (PV CT), which is performed at a fixed delay of 80 seconds at our institution.<br>|
| Cohort 14<br>+ 10 second time gap between routine abdominal CT and add on CT, Noise index 14 | Diagnostic Test: CT scan<br>* Patients with colorectal liver metastases scheduled for abdominopelvic CECT will be consented to undergo an additional CT of their abdomen (termed add-on CT) within 15 seconds, before or after, their clinical portal venous phase CT (PV CT), which is performed at a fixed delay of 80 seconds at our institution.<br>|
| Cohort 15<br>+ 10 second time gap between routine abdominal CT and add on CT, Noise index 16 | Diagnostic Test: CT scan<br>* Patients with colorectal liver metastases scheduled for abdominopelvic CECT will be consented to undergo an additional CT of their abdomen (termed add-on CT) within 15 seconds, before or after, their clinical portal venous phase CT (PV CT), which is performed at a fixed delay of 80 seconds at our institution.<br>|
| Cohort 16<br>+ 15 second time gap between routine abdominal CT and add on CT, Noise 12 | Diagnostic Test: CT scan<br>* Patients with colorectal liver metastases scheduled for abdominopelvic CECT will be consented to undergo an additional CT of their abdomen (termed add-on CT) within 15 seconds, before or after, their clinical portal venous phase CT (PV CT), which is performed at a fixed delay of 80 seconds at our institution.<br>|
| Cohort 17<br>+ 15 second time gap between routine abdominal CT and add on CT, Noise 14 | Diagnostic Test: CT scan<br>* Patients with colorectal liver metastases scheduled for abdominopelvic CECT will be consented to undergo an additional CT of their abdomen (termed add-on CT) within 15 seconds, before or after, their clinical portal venous phase CT (PV CT), which is performed at a fixed delay of 80 seconds at our institution.<br>|
| Cohort 18<br>+ 15 second time gap between routine abdominal CT and add on CT, Noise 16 | Diagnostic Test: CT scan<br>* Patients with colorectal liver metastases scheduled for abdominopelvic CECT will be consented to undergo an additional CT of their abdomen (termed add-on CT) within 15 seconds, before or after, their clinical portal venous phase CT (PV CT), which is performed at a fixed delay of 80 seconds at our institution.<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| assess the stability (reproducibility) of radiomic measurements obtained from repeat abdominal CT scans | There will be 18 cohorts, each cohort differing by the length of the time gap in acquisition and noise index. In addition each acquisition will be reconstructed in 21 different ways (combinations of 3 slice thicknesses and 7 ASiR levels). | 2 years | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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colorectal liver metastases, CT scan, 17-010