Early Detection and Monitoring of Cancer
Similar to screening, the goal of early detection is to reduce the cancer death rate and, by detecting cancer early before signs or symptoms of cancer appear, improve the likelihood of successful treatment.
Not only would early detection of cancer reduce mortality, but it would also save both the affected individuals and the health system money, in terms of treatment dollars, disability dollars, and lost productivity dollars.
In screening for specific cancers, there is usually insufficient scientific evidence to indicate that population based screening will reduce mortality. And due to the high specificity of most cancer tests, the cost and inconvenience of the test for the individual is high. The costs of screening and insufficient scientific evidence, usually outweighs the utility of identifying the disease at an earlier stage when treatment tends to be more effective.
What we hope to achieve, is to introduce a test that will be able to reveal the disease earlier in its growth than does the customary way in which the disease is found. Due to the test's non-invasive and simple nature for the individual users, appropriate testing intervals (neither too often nor not often enough) would allow a greater ease of gathering meaningful data (statistical significance) from the general population. In cancer, it is changes at the cellular level that initiates the disease. When this cellular alteration occurs, elevated levels of cell-free DNA related to the cancer may be found circulating in the body. This change at the DNA level is a very early indication of altered health. Elevated levels of DNA can be used as prognostic tool to detect cancer at its earliest stage.
More importantly, circulating levels of DNA can also be used to monitor for cancer recurrence/relapse or to establish cancer free status/remission of an individual. The use of this test to monitor the efficacy of cancer treatment eliminates some of the objections that may be raised when using this test for early cancer detection purposes. High specificity or overdiagnosis (benign tumour detection) are no longer issues because for disease state monitoring, the cancer has already been identified and treatment is ongoing or has already been administered. Monitoring also provides a peace of mind, first-look at treatment efficacy and remission status. This is very important for cancer survivors, where vigilance and diligence will always remain a priority. Increased levels of Cell-free DNA, relapse, would indicate that the cancer was not cured, while continued decreased levels of Cell-free DNA would indicate that the cancer was successfully removed, remission.
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