13 doctors weighed in:
Can an abdominal pelvic cat scan screen for colon cancer or see a mass in the rectum?
13 doctors weighed in

Dr. Robert Green
Internal Medicine - Oncology
6 doctors agree
In brief: Sometimes
Sometimes a cat scan will be able to see a mass in the colon or rectum but it is not a good test for screening for colorectal cancer.
There is a specialized type of ct scan that creates a virtual image of the inside of the colon that is sometimes used when a patient is not a good candidate for a colonoscopy.

In brief: Sometimes
Sometimes a cat scan will be able to see a mass in the colon or rectum but it is not a good test for screening for colorectal cancer.
There is a specialized type of ct scan that creates a virtual image of the inside of the colon that is sometimes used when a patient is not a good candidate for a colonoscopy.
Dr. Robert Green
Dr. Robert Green
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Dr. Carlo Contreras
Surgery - Oncology
6 doctors agree
In brief: Potentially
If the masses are large enough, they can be seen on cat scan.
In order to increase the chances of these being seen, the cat scan has to be administered as a "ct colonography". Oral contrast agent needs to be swallowed, and an air enema needs to be administered during the ct scan. Traditionally, colonoscopy is considered the most reliable and accessible way to screen for colorectal cancer.

In brief: Potentially
If the masses are large enough, they can be seen on cat scan.
In order to increase the chances of these being seen, the cat scan has to be administered as a "ct colonography". Oral contrast agent needs to be swallowed, and an air enema needs to be administered during the ct scan. Traditionally, colonoscopy is considered the most reliable and accessible way to screen for colorectal cancer.
Dr. Carlo Contreras
Dr. Carlo Contreras
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Dr. John Lipman
Radiology
2 doctors agree
In brief: Possibly & Yes
These are 2 different scenarios.
Screening is performed in asymptomatic patients. You can screen for colon cancer with a special type of ct scan called virtual colonscopy. If a polyp is found it would still need to be removed with a colonscopy masses in the rectum can be seen with a pelvic ct scan.

In brief: Possibly & Yes
These are 2 different scenarios.
Screening is performed in asymptomatic patients. You can screen for colon cancer with a special type of ct scan called virtual colonscopy. If a polyp is found it would still need to be removed with a colonscopy masses in the rectum can be seen with a pelvic ct scan.
Dr. John Lipman
Dr. John Lipman
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1 comment
Dr. Andrew Turrisi
It "sees" large things, and is diagnostic rather than screening, and always requires biopsy confirmation to prove cancer. Things following up symptoms and signs are not true screening, which is for those without either symptoms or signs
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Dr. Arnon Rubin
Board Certified, Internal Medicine
20 years in practice
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