Leading expert in virtual colonoscopy, Dr. Perry Pickhardt, MD, explains how CT colonography detects cancers outside the large bowel. He details the significant advantage of extracolonic findings. Dr. Pickhardt reveals that virtual colonoscopy finds more cancers outside the colon than inside it. The detection rate for these extracolonic cancers is approximately 1 in 300 examinations. These findings include renal cell carcinoma, liver cancer, lymphoma, and lung cancer. The procedure also screens for abdominal aortic aneurysms and osteoporosis.
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Virtual Colonoscopy for Extracolonic Cancer Detection and Screening
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- Virtual Colonoscopy Advantages Beyond the Colon
- Extracolonic Cancer Detection Rates and Types
- The Significance of Incidental Findings
- Additional Screening Benefits of CT Colonography
- The Future of CT Abdominal Screening
- Full Transcript
Virtual Colonoscopy Advantages Beyond the Colon
Dr. Perry Pickhardt, MD, highlights a key benefit of virtual colonoscopy. The procedure provides a comprehensive diagnostic CT scan of the abdomen. This scan evaluates organs beyond the large bowel. Patients receive an examination of their kidneys, liver, and the bases of their lungs. Dr. Anton Titov, MD, discusses how this capability can identify serious problems early.
Dr. Pickhardt views these extracolonic findings as a major advantage, not a drawback. He explains that this feature transforms the screening test. It offers a more complete health assessment for asymptomatic patients.
Extracolonic Cancer Detection Rates and Types
Dr. Perry Pickhardt, MD, provides crucial data on cancer detection. Virtual colonoscopy finds a cancer outside the colon in about 1 in every 300 patients. This detection rate is significant for a screening test in healthy individuals.
These extracolonic cancers can include renal cell carcinoma and liver cancer. The scan can also detect lymphoma and lung cancer at the base of the lungs. Dr. Perry Pickhardt, MD, notes that any organ within the scan's field of view can be involved.
Interestingly, Dr. Anton Titov, MD, learns that this rate is higher than for colorectal cancer itself. Virtual colonoscopy finds more cancers outside the colon than inside it during screening.
The Significance of Incidental Findings
The issue of "incidentalomas" is central to modern radiology. Dr. Perry Pickhardt, MD, clarifies that this is not unique to CT colonography. It applies to any cross-sectional imaging like CT or MRI scans.
He describes this as a double-edged sword. The challenge is to focus workups only on findings of legitimate clinical significance. When managed correctly, these incidental findings become a powerful tool for early diagnosis.
Dr. Perry Pickhardt, MD, emphasizes the importance of expert interpretation. This minimizes unnecessary follow-up tests and procedures for patients.
Additional Screening Benefits of CT Colonography
Dr. Perry Pickhardt, MD, outlines further advantages of the virtual colonoscopy exam. The procedure can screen for abdominal aortic aneurysms. This eliminates the need for a separate ultrasound screening as currently recommended by guidelines.
CT colonography also allows for osteoporosis screening. The scan can provide bone density information. This could potentially reduce the need for a dedicated DEXA scan in some patients.
Dr. Anton Titov, MD, discusses how this multi-purpose screening adds tremendous value. It makes virtual colonoscopy a highly efficient preventive health tool.
The Future of CT Abdominal Screening
Dr. Perry Pickhardt, MD, is optimistic about the evolution of this technology. He suggests we may not always call the procedure CT colonography. It could be renamed as a comprehensive CT abdominal screening exam.
This reflects the broader diagnostic potential of the scan. As more data becomes available, the significant advantage of extracolonic evaluation will become clearer. Dr. Pickhardt believes this will lead to wider global acceptance of the technique.
Dr. Anton Titov, MD, concludes that virtual colonoscopy presents a new paradigm for cancer screening. It offers a powerful combination of colorectal and extracolonic evaluation in a single test.
Full Transcript
Virtual colonoscopy is a CT scan of the abdomen. How often does CT colonography find cancers outside the large bowel? What is the significance of "incidental findings" during virtual colonoscopy? A leading virtual colonoscopy screening expert discusses CT colonography.
One advantage of virtual colonoscopy is the ability to identify potentially serious problems outside of the colon.
Dr. Anton Titov, MD: During CT colonography, patients get a large bowel evaluation. They also receive a diagnostic CT scan of their kidneys, liver, and bases of the lungs. It is known that Steve Jobs' pancreatic cancer was initially discovered on a screening CT scan. He had a CT of the abdomen for other reasons. How do you view the opportunity to find serious problems outside of the colon with CT colonography?
Dr. Perry Pickhardt, MD: The meaning of "incidentalomas" has been quite controversial. What is the potential significance of findings outside the colon? How often do you discover cancers? Kidney or liver cancer, or even lung cancer.
Dr. Anton Titov, MD: What are the problems outside the colon that you see during screening virtual colonoscopy?
Dr. Perry Pickhardt, MD: Sure. This is an issue that is related not just to CT colonography. The incidental findings issue is relevant for any cross-sectional imaging. In any patient getting a CT scan, we see other organs beyond the intended target. With CT colonography, we call these extracolonic findings. But the "incidentaloma" issue applies to our entire practice of radiology.
I view this as a double-edged sword. A lot of people assume this is a drawback or disadvantage of virtual colonoscopy. CT colonography finds things outside of the colon. It is not possible for the radiologist to clearly limit workup to only those things that are truly of legitimate significance.
By doing that, we actually turn the equation around completely. Extracolonic findings are a huge advantage of virtual colonoscopy. We screen for abdominal aortic aneurysms. You don't need an ultrasound in addition to the colonoscopy. Current guidelines call for abdominal aortic aneurysm screening by ultrasound.
We can do osteoporosis screening during virtual colonoscopy. The patient doesn't really need their bone densitometry study, for example. We can find a cancer in completely healthy asymptomatic 50- to 60-year-old patients. We find a cancer outside of the colon in about 1 of every 300 patients.
That might be a lung cancer at the base of the lungs. It might be a renal cell carcinoma or a lymphoma. Any organ can potentially be involved.
Dr. Anton Titov, MD: All of those cancers add up. The rate of cancer detection outside the large bowel is roughly 1 in 300. But only 1 in 500 patients who have virtual colonoscopy will have a colon cancer found. It is the large polyps being the reason we are screening, not so much looking for cancers themselves in the colon.
Dr. Perry Pickhardt, MD: But it is an interesting fact that virtual colonoscopy, as a colorectal screening test, finds more cancers outside of the colon than inside of the colon. It is a very powerful combination. The additive value of that extracolonic evaluation makes virtual colonoscopy the best.
In the future, we may not be calling it CT colonography. Maybe we call it a CT screening or an abdominal screening exam. This is actually very interesting because you are more likely to find cancer outside of the colon while doing CT colonography.
Dr. Anton Titov, MD: That presents virtual colonoscopy in a different light for colon cancer screening. CT colonography is more widely accepted around the world. Then more and more data will be available for meta-analysis.
Dr. Perry Pickhardt, MD: Yes, that is correct. We will also show over time that this problem of unnecessary workup can be reduced to a minimum. I am very hopeful for this extracolonic evaluation of other organs for cancer. It will prove to be a significant advantage to CT colonography.
Virtual colonoscopy detects cancers outside the colon. What is the significance of extracolonic findings? Virtual colonoscopy for cancer screening outside the colon. The chance to find cancer outside the colon during a virtual colonoscopy examination is higher than to find colorectal cancer. It is approximately 1 in 300 virtual colonoscopy examinations. Cancers of kidneys, liver cancer, or even lung cancer.
What are the problems outside the colon that you see in virtual colonoscopy in asymptomatic patients? The incidental findings issue is relevant for any of our cross-sectional imaging (CT, MRI). An incidentaloma is seen frequently on CT scans. The "incidentaloma" issue applies to our entire practice of diagnostic radiology. We can find a cancer in completely healthy asymptomatic 50- to 60-year-old patients.