07 Jun Simple Blood Test May Help Assess Risk of Colorectal Cancer
MedicalResearch.com Interview with:
Gilles Jobin, MD, FRCP, MSc
Chief of Gastroenterology
Maisonneuve-Rosemont Hospital
Associate Professor of Medicine
University of Montreal
Montréal, Qc
MedicalResearch.com: What is the background for this study?
Dr. Jobin: It is known that the immune system has a role to play in keeping the body free of cancer and tumor cells. There is a lot of scientific literature that shows that when someone has cancer, certain cells from the immune system do not function very well. These cells are called natural killer or NK cells and they are the first ones to respond when there is a virus, a bacteria or a tumor cell in the body.
If the activity of these cells is very low, then there is a higher risk of someone developing a cancer, and if someone has cancer, there are greater chances that their NK cell activity is low.
In the last few decades, a few tests have been developed to measure NK Cell activity but they have been used in research only because they were complicated and difficult to use.
The current study measured NK Cell activity (NKA) with a new commercially available simple blood test to investigate its clinical application in the detection of colorectal cancer in patients presenting for prescribed colonoscopy. The aim of this study is to evaluate the sensitivity, specificity, positive and negative predictive values of this in vitro diagnostic device in patients with colorectal cancer (CRC) and adenomatous polyps (AP).
MedicalResearch.com: What are the main findings?
Dr. Jobin: In our research, we looked at whether we could confirm that patients who were diagnosed with colorectal cancer (also called CRC) by colonoscopy would have low NK cell activity. This research tested the activity of NK cells in more than 800 people coming to our hospital for colonoscopy. We showed that indeed, those patients who had CRC had very low NK cell activity, making this test highly sensitive for this type of cancer.
In this population, the prevalence was 2.8% for CRC and 13.4% for AP of 10 mm or higher
In the 762 evaluable subjects, statistically significant differences were found between the NKA of patients positive for CRC (n=21) and that of patients negative for CRC (n=741)
CRC mean 344.2 pg/mL (SD:881.7)
CRC-negative mean 731.5 pg/mL (SD:1019.3), p=0.001
CRC median 87.0 pg/mL (IQR:49.0-151.0)
CRC-negative median 294.8 pg/mL (IQR: 98.7-895.5), p≤0.001
Receiver Operator Characteristics (ROC) analysis of the data show that the optimum cut-off for detection of CRC is 181.3 pg/mL, with an area under the curve of 71%
At a cut-off of 200 pg/mL, sensitivity of the IVDD for detection of CRC was 85.7%, with a specificity of 59.6%, positive and negative predictive values of 5.7% and 99.3% respectively The positive and negative predictive values adjusted for prevalence of CRC in an average risk population (at 0.5%) were 1.1% and 99.9% respectively.
At a cut-off of 200 pg/mL, sensitivity of the IVDD for detection of AP 10 mm or higher was 42.2%, with a specificity of 58.3%, positive and negative predictive values of 13.5% and 86.7% respectively. At a cut-off of 500 pg/mL, sensitivity was 56.9%, with a specificity of 35.0%, positive and negative predictive values of 11.9% and 84.0% respectively
MedicalResearch.com: What should readers take away from your report?
Dr. Jobin: The present study using a new simple blood test confirms that the measurement of NKA may be a useful tool in clinical practice to assess the risk of colorectal cancer. These interesting results must now be confirmed in a population-based screening study.
As demonstrated in our results, the characteristics of this test are interesting. The results show that the test could be useful in assessing the risk of colorectal cancer in patients presenting for a colonoscopy, could therefore be helpful in assessing the importance and urgency of these colonoscopies and could help in the management of our waiting list for this procedure. These results also encourage us to look at the use of this test as a screening tool in an average risk population.
MedicalResearch.com: What recommendations do you have for future research as a result of this study?
Dr. Jobin: Our study was conducted in a higher risk population (symptoms, personal or family history, etc.). More studies are needed to:
• – Document the use of this test in an average risk population and therefore confirm its role in colorectal screening programs
• – Document the evolution of NK Cell activity after surgery (removal of polyps or tumours)
MedicalResearch.com: Thank you for your contribution to the MedicalResearch.com community.
Citation:
A New Blood Test for the Detection of Colorectal Cancer (CRC): Measurement of Natural Killer Cell Activity (NKA) in Patients Undergoing Colonoscopy
Presentation Number: Tu2088
Author Block: Gilles Jobin1,2, Mathieu Provençal3, Guy Aumais1,2, Louis-Charles Rioux1,2, Karl Herba1,2, Gidej Durivage1,2, Jean-René Lachance1,2, Karen Matouk1,2
1 Department of Medicine, University of Montreal, Montreal, Quebec, Canada; 2Division of Gastroenterology, Maisonneuve-Rosemont Hospital, Montreal, Quebec, Canada; 3Department of Biochemistry, Maisonneuve-Rosemont Hospital, Montreal, Quebec, Canada
Note: Content is Not intended as medical advice. Please consult your health care provider regarding your specific medical condition and questions.
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Last Updated on June 7, 2016 by Marie Benz MD FAAD