Skip to 0 minutes and 7 seconds On the other hand, in clinic, pathologist based on the tissue histology and cell morphology from biopsy to give a score such as TNM scoring system to staging and describe the progression of cancer development. What is TNM staging system? T describes the size of the tumor, usually the tumor remains in the primary organ at this stage. N described how the nearby lymph nodes are invaded by the tumor. M described the migration of the tumors to the distal organs. However, Biomarker candidates must undergo clinical verification and validation before actually receiving regulation agent approval and becoming a routine biomarker. For most of the candidate markers, the clinical validation process is just beginning.
Skip to 1 minute and 13 seconds There are modern methods and technology be used to identify the biomarkers and applied the biomarkers to drive clinical practice. Such as DNA microarray is to identify disease related irregular gene expressions profile; Flow cytometry use specific antibodies that recognize cell surface protein to identify typical cells. Tissue microarray and ELISA also use specific antibodies that can identify the disease related abnormal protein expressions. These modern molecular biomarkers may need to be incorporated into pathological staging system such as TNM for clinical validation. More importantly, it must also demonstrate clinical value of using these biomarkers beyond those information that are already available at the time of diagnosis by using traditional method.
Skip to 2 minutes and 20 seconds After identified a potential clinically useful biomarker, a reliable detecting method also needs to be developed. The ideal biomarker assay should be sensitive, specific, cost-effective, fast, and robust. In addition, it should be against inter-operator and inter-institutional variability. The biomarkers and the assay system for measuring the biomarkers have to be validated carefully. Could the potential biomarker be sensitive and specific enough to represent a pathological condition? What kind of the specimen needs to be collected for testing? Is it convenient or low risk for collecting the specimen from patients? Is there interference to the test, eg, needs fasting or not before collecting the samples for testing, would menstrual cycle, drug, or dietary supplement may interfere the test? Does the biomarker express in typical population?
Skip to 3 minutes and 37 seconds Does age or sex affect? Based on the developed test results and the gold standard of clinical diagnosis, one can draw a two by two plot indicating the performance of sensitivity, specificity, precision and accuracy of the developed test, To evaluate whether the newly developed test is clinically valuable. Is the false positive or false negative rate acceptable compared to the clinical gold standard diagnosis? All of the issues described above need to be concerned and validated. The main challenge of translational research for biomarkers is, extensive analytical and prospective clinical testing data are required for FDA approval and clearance. Many of new tests are conducted on tissue rather than on standard serum or plasma samples. There for requiring new and detailed sample-stability testing protocols.
Skip to 4 minutes and 53 seconds Many tests employ algorithms for the interpretation of analyte measurements, in order to provide a single result; however, the analytical process is not fully transparent, thereby posing a regulatory risk. Finally, could the test be affordable, and be beneficial to the most patients also need to be concerned. We hope you enjoy in today’s class!
TNM staging system vs. molecular diagonosis
In traditional clinical practice, physicians usually use the TNM staging system to describe a patient’s cancer condition.
In this video, Prof. Yang will introduce a new concept, the molecular diagnosis. This is a new way of looking at “tumor”, “cancer”, or other diseases.