Characterizing the Aggressiveness of Prostate Cancer with Multimodality Imaging
Abstract
Most laypeople have formed a belief that cancer of any type is lethal and requires immediate aggressive treatment. This is an important psychological factor that influences treatment decisions for newly diagnosed prostate cancer. Although approximately 50% of these men will be diagnosed with slowly growing (low-risk) prostate cancer, most men and their physicians will opt for aggressive treatment. These low-risk patients receive little benefit from this overtreatment, but often experience significant treatment complications, including erectile dysfunction (90%), urinary incontinence (50%), and gastrointestinal side effects (70%). Most men with low-risk prostate cancer will die with this disease, not as a result of it. Overtreatment of prostate cancer is one of the most challenging problems in the health care of men. It is an extremely important public health issue that consumes significant healthcare resources and reduces quality of life for men afflicted with this disease. The problem of overtreatment arises partly from how prostate cancer is diagnosed. Men who have a positive digital rectal exam or an elevated prostate-specific antigen (PSA) test undergo an invasive biopsy where 12 needle core samples are taken systematically throughout the prostate. Since only a small portion of the prostate is sampled and tested, there is a risk of missing small cancerous regions or sampling only the less aggressive ones. This leads to an uncertain diagnosis based on biopsy alone and, as a result, conservative decision-making. In fact, some physicians advise treatment for all patients instead of active surveillance, where low-risk prostate cancer is not treated but is monitored for any significant changes that might indicate that the cancer is becoming more aggressive. This situation can be corrected by improved diagnostic tools based on new imaging methods (a goal of this research) that can non-invasively and confidently determine the aggressiveness of tumors throughout the entire prostate. Molecular imaging is a new method of non-invasively measuring important biological processes inside tumors without using an invasive biopsy. In this project, we will use a non-invasive molecular imaging assay and demonstrate its capability to improve the detection of prostate tumors throughout the entire prostate and determine their aggressiveness. This molecular imaging assay will combine clinical magnetic resonance imaging (MRI) methods with state-of-the-art MRI techniques to measure the concentration of naturally occurring sodium in the prostate and the addition of positron emission tomography (PET) to measure the presence of a protein (known as PSMA) found on prostate tumor cells. Elevated amounts of sodium or PSMA are indicative of prostate cancer and can be used to differentiate between low- and high-risk cancer for better diagnosis and improved treatment decisions. Improved cancer identification and enhanced active surveillance using molecular imaging methods, combined with training of physicians and patients to accept them, will increase the confidence of men with low-risk disease to choose active surveillance using molecular imaging to assess possible changes in the aggressiveness of the prostate lesions instead of immediate and aggressive treatment. This Idea Development Award will demonstrate the ability of our molecular imaging to improve detection of prostate tumors and accurately determine their aggressiveness by comparing non-invasive molecular imaging to pathological examination, an invasive but infallible means of diagnosis. This project will study 45 men with biopsy-proven prostate cancer. Prior to prostatectomy, they will undergo molecular imaging. After surgery, sections of their prostates will be examined under a microscope by a pathologist. This examination is the gold standard for characterizing tumors and will be used to establish how accurately the pre-surgical molecular imaging assay was able to fin
Document Details
- Document Type
- DoD Grant Award
- Publication Date
- Nov 19, 2019
- Source ID
- W81XWH1910721
Entities
People
- Timothy J Scholl
Organizations
- United States Army
- Western University