RECAF

The best weapon against cancer has been demonstrated to be early detection. Unfortunately, the methods available to accelerate cancer detection are limited (PSA for prostate cancer, mammograms for breast cancer, Pap smears for cervical cancer and colonoscopy for colorectal cancer are the most commonly used). While there is controversy on the use of PSA, with two large studies appearing in the New England Journal of Medicine; one concluding that the impact of prostate screening for saving lives is marginal and the other claiming that it reduces mortality by 20%, the marker continues to be used 50 million times every year! The impact of programs designed for early detection of breast and cervical cancers is undeniable.

Unlike other commonly used cancer markers, RECAF is elevated in early stages of breast and prostate cancers, when the cure rates are the highest. There is no particular reason why this feature should be limited to those two malignancies (which for practical reasons are the only two we have studied so far) and therefore it is reasonable to expect that RECAF will be able to detect other types of cancer in the early stages.

The sensitivity and specificity data found in these studies is shown in the following two tables:

The following statistics illustrate the importance of early diagnosis in relation to the outcome of breast cancer: patients diagnosed at Stage I have a 5 year survival of 87%. At Stage II the 5 year survival rate is still high (75%). Survival drops to 46% when the patient is diagnosed at Stage III and at Stage IV it is only 13%.

Please note that these values of sensitivity/specificity are unobtainable with PSA or any other available diagnostic tool other than a biopsy.

Also note that a biopsy can grade how aggressive a prostate cancer is and therefore a positive result does not necessarily result in treatment but rather in a biopsy which in turn determines the course of action; all RECAF does is to provide a more accurate indication than PSA as to whether or not a biopsy is needed.

We have been able to detect RECAF in saliva and while the test performance is not as good as its serum counterpart, the logistics and cost of collecting large numbers of saliva samples are very favorable when compared to blood extraction. A way to marry the higher performance of blood testing with the lower cost of saliva testing is to design the saliva assay so that it detects as many cancers as possible and then sort out the false positives with a blood test on those individuals whose saliva tested positive.

This is perhaps one of the most promising uses of the RECAF cancer test. Following treatment, CEA, CA125 and PSA are used for monitoring recurrence of colorectal, ovarian and prostate cancer respectively.

Unfortunately there is only a handful of markers available for a small number of malignancies. On the other hand, RECAF works for all cancers and since the type of cancer will already be known to the Oncologist, using one test for monitoring a variety of cancers is very convenient and considerably cheaper given the economies of scale resulting from using the same test in all cancer patients.