Cancer DNA Detection in Blood and Urine

The American Cancer Society estimates that approximately 29,480 men will die of prostate cancer in the United States in 2014. Many of these men were initially diagnosed with aggressive prostate cancer (so-called "high risk" prostate cancer), often with cancer that extended beyond the prostate gland itself or was of a high Gleason score, or was associated with a Prostate Specific Antigen [PSA] level > 20 ng/ml. In contrast to the more favorable outcomes in men with low and intermediate risk disease, nearly 50% of men with high-risk prostate cancer will have a recurrence of their cancer despite a complete course of treatment. One of the mainstays of care for men with high-risk prostate cancer is a combination of radiation therapy and hormone suppression (more appropriately called androgen deprivation [ADT]). Despite advances, a clear need exists for improved clinical management of high risk disease.

One of the challenges in the overall management of men with high risk prostate cancer is the lack of a reliable test allowing clinicians to monitor tumor response both during and after radiation therapy. The commonly used marker, prostate specific antigen (PSA), is less useful in men receiving ADT. In these men, the PSA is level is strongly suppressed by the ADT and is a less reliable surrogate for detecting active tumor. Importantly, ADT is given both during and for up to 3 years following radiation therapy, limiting the utility of PSA testing for an extended period of time during which the window for curative therapies may close. The development of an accurate, noninvasive monitoring test is needed, to guide early implementation of salvage strategies aimed at increasing the proportion of patients cured of their disease.

Prior research from our group and several others has demonstrated that prostate cancers nearly universally harbor stable, cancer-specific changes (modifications) of the DNA. Furthermore, published studies have shown that this modified (methylated) DNA can be readily detected in urine and blood specimens from men with primary prostate cancer.

Investigators hypothesize that large scale assessment of cancer-specific DNA changes and rearrangements in the urine and plasma of prostate cancer patients using technology developed by our group (qMBD-seq), will allow for more informative and accurate tracking of disease burden and therapeutic response in men receiving radiation therapy and ADT for high-risk prostate cancer.

Investigators have two straightforward primary objectives for this pilot study. First we will establish the background levels of modified DNA in individuals with no history of prostate cancer. Second, investigators will quantify cancer-specific methylated DNA in men with known high risk prostate cancer. Investigators will begin by collecting urine and plasma specimens from normal volunteers. In parallel investigators will collect specimens for quantitation of cancer-specific DNA modifications in men with known high-risk prostate cancer receiving standard treatment in the Department of Radiation Oncology. Patient samples will be collected at multiple time points before, during, and after radiation treatment and then will be subjected to careful DNA sequencing and analysis. This will allow investigators to simultaneously characterize and quantify prostate cancer specific DNA occurring anywhere in the genome, thereby allowing investigators to predict which patients have prostate cancer still present in their body after treatment even if the PSA is very low or undetectable. If successful, this project will be an important first step in the development of a noninvasive test to track disease burden and therapeutic response during and after radiation therapy for high-risk prostate cancer.