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Posts Tagged ‘CT Colonography’

Have an overview, how computed tomography is viable for bowel/colorectal cancer!

 

In Computed tomography, as we know, X-rays are used to scan body organs/tissues, where a computer unit is employed for cross-sectional image (slice) construction. The technology is feasible for a variety of medical conditions; in case of patients with cancer/colorectal polyps, CT colonography (virtual colonoscopy) is a practicable approach over traditional colonoscopy procedure, for the diagnosis.

Colonoscopy (endoscopic procedure) is commonly used to visualize interior of the colon/large intestine for irregular growths, tissue inflammation, bleeding and ulcers. The large bowel cancer includes cancerous growth on colon, rectum/alimentary canal, appendix; in the U.S., death rate due to colon/colorectal cancer is high, in contrast to other medical conditions.

For patients suspected of cancer/polyps in the large intestine, computed tomography colonography is a feasible approach for early-stage detection of such, so that the tumor could be taken out, prior it develops further.

People that have a family history, or at increased risk of colorectal cancer (malignant disorder) are proposed for an early scan; men and women, 50+ years are even suggested to go for colon cancer/polyps screening, taking expert consultation.

Various medical groups/associations suggest individuals for – CT colonography once in every 5 years, and colonoscopy in every 10 years.

Stay tuned with MedicExchange, for various health related blogs and stories, from the radiology community, and related!

The random finding of a renal mass is comparatively common at unenhanced computed tomography; imaging standard can be applied for reliable identification of majority of these lesions as benign without extra diagnostic examination.

The medical research study was conducted by Stacy D. O’Connor, Perry J. Pickhardt, David H. Kim, M. Raquel Oliva and Stuart G. Silverman from Department of Radiology, University of Wisconsin School of Medicine and Public Health, Madison, WI; Department of Radiology, Brigham and Women’s Hospital, Harvard Medical School, Boston, MA.

The study is available in American Journal of Roentgenology, and the research objective was to explore the incidence and clinical relevancy of the accidental findings of renal masses at low-dose unenhanced CT, and to identify the results for characteristics that can be utilized to lead assessment.

Image data of unenhanced CT colonography (examinations) of about 3001 sequentially registered patients – both men and women (mean age: 57 years) without symptoms were retroactively examined for appearance of solid and cystic renal masses, 1 cm in diameter, or larger than that. Index mass in each patients was evaluated for morphologic features, size, mean attenuation etc.

Masses with attenuation less than 20 HU or greater than 70 HU, or comprising fat were termed benign, if they did not comprise septation/thickened walls, mural nodules or thick calcifications. Masses that had attenuation in the range of 20 and 70 HU, or any of these characteristics were termed vague. The diagnostic performance of CT colonography in discovery of renal cell carcinoma was gauged for masses, with 2 or more years of further observation.

About the findings, at the least one renal mass was recognized in about 433 patients. Except for 13.2% indeterminate cases, about 86.8% masses (376 patients) were categorized as benign; mean size of index masses was 25 ± 16 mm. The attenuation zone of 20–70 HU was utilized for sorting 53 indeterminate lesions. Further data were obtainable for 81.5% of cases (353 patients), with 312 benign, and 41 indeterminate masses – 4 of this were analyzed as renal cell carcinoma.

On grounds of indeterminate criteria, the specificity and sensitivity for renal cell carcinoma were 89.4% and 100% respectively; the negative and positive predictive values were 100% and 9.8%, in the relative manner.

Conclusion: The accidental finding of a renal mass is comparatively common at unenhanced computed tomography, but imaging standard can be utilized for reliable recognition of majority of these lesions as benign without extra diagnostic examination. Mean attenuation solely seems reliable for concluding which renal masses require further assessment.

Compared to non-seniors, extracolonic findings were more rapid in seniors, despite there was no statistical deviation in rate of recommendation for additional imaging amid both the groups.

 

The medical research study was conducted by Michael Macari, MD, Gregory Nevsky, MD, John Bonavita, MD, Danny C. Kim, MD, Alec J. Megibow, MD, MPH and James S. Babb, PhD from the Department of Radiology, New York University School of Medicine, New York, NY.

The study is available in online journal of Radiological Society of North America, and the research objective was to retrospectively assess the rate of recommendations for additional imaging for significant extracolonic findings and prevalence of polyps amongst group of senior citizens (above 65 years of age), and non-seniors (below 65 years of age) experiencing low-dose computed tomography colonography.

HIPAA compliant, and approved by institutional review board, the study was comprised of 454 patients, which had 204 non-seniors, and 250 seniors – they underwent CT colonography at outpatient clinic. The cases were prospectively indicated by abdominal radiologist, skilled in CT colonography – the reports were examined for determination of frequency of polyps, extracolonic findings and recommendation for additional imaging (RAI).

For the non-senior group, the percentage for at least one reported polyp was 14.2%, and for seniors – it was 13.2%, and not significantly different. The percentage level for at least one extracolonic with non-seniors was 55.4%, where as for seniors – it was 74.0%. recommendation for additional imaging of 4.4% for non-seniors and 6.0% for seniors was not significantly different.

Conclusion: Compared to non-seniors, extracolonic findings were more rapid in seniors, despite there was no statistical deviation in rate of recommendation for additional imaging amid both the groups.

CT Colonography or Virtual Colonoscopy can detect colonic as well as extra-colonic abdomino-pelvic lesions, an added advantage over colonoscopy.  Virtual colonoscopy uses computerized tomography (CT) to produce hundreds of cross-sectional images of the abdominal organs which are analysed tp produce a veirtual image of the inside of the colon and rectum while colonoscopy is the endoscopic examination of the colon using a colonoscope allowing direct vizualisation of the colon and rectum.

The new findings were reported in the September issue of the American Journal of Roentgenology.

Even though CT colonography (CTC) cannot be compared to CT pelvis and abdomen, the extracolonic findings detected during the procedure can be significant and provides a clear advantage over conventional optical colonoscopy Dr. Ganesh R. Veerappan, MD, of Walter Reed Army Medical Center in Washington and colleagues conducted a retrospective study to analyse the significance of these lesions.

The researchers found that out of the 2277 patients who underwent CTC, about 45 percent cases had extracolonic findings and a quarter of these findings were significant. Further radiology procedures, surgery and follow-up revealed 7 high-risk lesions among the significant lesions and the radiology studies added approximately $50 extra per patient. The virtual colonoscopy examination found six intracolonic malignancies and three adenomas with high-grade dysplasia.

“CT colonography [CTC] not only identifies colorectal cancer [CRC] but also doubles the yield of identifying significant early extracolonic lesions, resulting in lives saved,” Ganesh Veerappan reported in the journal.

The team concluded that the odds of identifying high-risk lesions were raised by 78% with CTC and thus the examination should be considered as an alternative to conventional colonoscopy in colo-ractal cancer screening or as a one-time screening procedure for intracolonic and extra-colonic lesions.

A study suggests that Virtual colonoscopy or CT colonography can detect malignant cancer outside the colon. According to the study, one out of every 200 people having no symptom of disease possess unsuspected malignant cancer, that too outside the colon.

Colonoscopy is usually done to detect Colorectal cancer, which is supposed to be one of the leading causes of cancer death in U.S. It is recommended to start colorectal cancer screening for people with average risk at the age of 50, but the uneasiness caused by the conventional optical colonoscopy resist people from undergoing screening.

Compared to optical colonoscopy, Virtual colonoscopy has many advantages.

• Less invasive
• Produce detailed image of the interior portion of colon without inserting the scope into it
• The risk of bleeding in the colon, which usually occur with the optical colonoscopy is almost null
• It can be done without sedating the patient
• The structures outside the colon, like pelvis, abdomen and portions of the lungs can be assessed to a limit with this technique. In some cases, virtual colonoscopy is used to diagnose extracolonic parts and most of them appear to be clinically relevant.
• Cost effective
• Saves on time, taking just 10 minutes or less.

The study was conducted by Pickhardt, M.D., professor of radiology and chief of GI Imaging, at the University of Wisconsin School of Medicine & Public Health, and colleagues. For the study, the researchers selected 10,286 adults (5,388 men and 4,898 women) with a mean age of 59.8 years who showed no symptom of the disease. The selected population underwent colorectal cancer screening with virtual colonoscopy either at the University of Wisconsin or at National Naval Medical Center and their medical records were reviewed. It took a mean time 30.2 months for follow-up.

The results showed that 58 patients had unsuspected colorectal cancers, 22 patients had invasive colorectal cancer, extracolonic cancer was found in 36 patients and 31 patients with localized cancers.

Dr. Pickhardt commented,

Although extracolonic evaluation at screening CT colonography does carry some disadvantages, such as patient anxiety, inconvenience, or the potential for benign biopsy, our results suggest that early detection of asymptomatic extracolonic cancer represents an additional benefit of screening CT colonography that is not available with optical colonoscopy. Virtual colonoscopy is an accurate, safe and convenient screening test that could potentially be a life-saving examination.

University of Nebraska Medical Center (UNMC) lymphoma experts say that patients who are completely treated for lymphoma are recieving unnecessary Computed Tomography (CT) and Positron Emission Tomography (PET) examinations during their follow-up visits, often on the patient’s requests.

UNMC oncologist, Julie Vose, M.D., and co-author Malik Juweid, M.D. published their comments regarding this issue in a letter the editor in the March Edition of the ‘New England Journal Of Medicine’. They said that only a small percent of the Hodgkin’s lymphoma recurrences are diagnosed by PET/CT while majority is detected by the patient himself or during the doctor’s routine examination of the patient without imaging.

This leads to unnecessary radiation exposure and also unnecessary expediture. The radiation exposure has the risk of other cancers like lung and breast cancer.

During follow-up, physical examination, educating the patient about symtioms, routine blood tests and a yearly chest x-ray would be sufficient. Dr. Vose said that that the policy is not to do a scan unless there are symptoms or positive examination findings.

“In patients at low risk of recurrence, reducing the exposure to excessive radiation is an important goal,” she said.

The American College of Radiology (ACR) writes to Obama stating the benefits of CT colonography (CTC), also known as virtual colonoscopy, and his recent physical examination which included the test, as a rationale to require medicare coverage for the latest colorectal cancer screening technology.

Studies have shown that CTC is accurate as standard colonography and the benefits include low invasiveness, lack of sedation, lesser cost, much less procedure time and more importantly the patient can go back to work directly after the procedure which will attract more people to undergo the test and thus saves more lives.

Colorectal is the second leading cause of cancer deaths in the United States; and while Medicare denies CTC coverage, many private insurers like CIGNA, United Healthcare, and Anthem Blue Cross Blue Shield now cover screening as wellas diagnostic CT colonography. The congress needs to act to require Medicare coverage to CTC.

The American Cancer Society endorses CT colonography and added it to its list of recommended colorectal cancer screening exams and suggests that the exam be repeated every five years.

Even when the Medicare and Medicaid Services denies CT colonoscopy (CTC) coverage for senior citizens, President Obama himself underwent this screening test for colon cancer screening as part of his first physical exam as commander-in-chief.

CT colonoscopy (CTC), also called virtual colonoscopy, is a non-invasive test that is widely accepted by radiologists and gastro-enterologists as a patient friendly and quite effective screening test for large bowel cancer. Inspite of recommendations from organizations like American College of Radiology, and various studies supporting it,  the medicare has refused to cover the test.

Now the news that Obama has recieved virtual colonoscopy test has spiced up  the controversy again. The American College of Radiology (ACR) stated in their press release that the administration has to ensure that seniors have the same access as the President to this less invasive, cutting-edge care.

“……The President and his doctors have unparalleled access to the latest medical and scientific information. The fact that he opted for CTC should put to rest any empty arguments against the viability of CT colonography. It’s time for all patients who want a CT colonography to be covered for this lifesaving exam. Medicare needs to provide coverage now,”said James H. Thrall, MD, chair of the ACR Board of Chancellors.

Contrary to the opinion of ACR, American College of Gastroenterology (ACG) wrote to the President that “while a ‘virtual’ exam is better than no exam, for most people, colorectal screening by colonoscopy is the preferred strategy.”

ACG president Dr. Philip O. Katz, wrote that, “Our 11,000 physician members are concerned that you missed an important opportunity to set an example of the power of prevention by taking the test proven to prevent colorectal cancer by polyp detection and removal.”