New Imaging Approach to Map Prostate Cancer

Tuesday, June 11, 2013

Prostate cancer is the most common cancer diagnosed in men.

Annually, more than 26,500 of our fathers, grandfathers, brothers and sons are diagnosed with the disease and sadly 4,000 will likely succumb to it.

Researchers, led by Dr. Glenn Bauman, chair/chief, Department of Oncology, Schulich School of Medicine & Dentistry, and radiation oncologist are taking on this challenge by harnessing the power of advanced imaging techniques, leading to improved diagnosis and treatment.

"The Canadian Institutes of Health Research (CIHR) Team in Image Guidance in Prostate Cancer is leveraging the incredible expertise in prostate and imaging research in London," said Dr. Bauman. "Our goal is to develop new ways of accurately diagnosing men with prostate cancer who need treatment. We want to deliver the best treatment that will maximize the chance of cure with minimal side effects."

By evaluating various combinations of imaging techniques, such as magnetic resonance imaging (MRI), computed tomography (CT), positron emission tomography (PET) or ultrasound, the team aims to improve the ability to determine the location and amount of prostate cancer. This is information that is critical to accurately target a biopsy or select the most appropriate treatment.

The researchers are also seeking to identify a set of unique indicators on the hybrid (combined) images that best predicts how aggressive a cancer is likely to be. Finding better ways to identify men with low grade (slow growing) versus high grade (fast growing) prostate cancer will help to more effectively direct therapy.

The team compares the prostate imaging results acquired before surgery against the actual amount and location of the cancer seen in the prostate after its removal. This comparison is done using sophisticated means of imaging analysis developed during this project.

A rich database has been created that contains both the prostate imaging data and the related digitized pathology images from this study. This information will be extremely valuable in the development of computer-aided diagnostic tools. The database can also be used as an interactive educational tool by physicians like radiologists and radiation oncologists to shorten the learning curve for accurate interpretation of the hybrid prostate images.

As part of its evaluation of imaging techniques, the CIHR team participated in the development of a new type of PET imaging agent for prostate cancer, 18F-Fluorocholine. London was the first centre in Ontario to use this agent.

The group was also able to take advantage of a unique resource in the city, Canada's first and only PET/MRI scanner. Simultaneous imaging with 18F-Fluorocholine and MRI allows for perfect alignment of the MRI and PET images to maximize the diagnostic value of the imaging procedure. This represents a first in Canada for prostate imaging.

The ultimate aim of this research is to improve prostate cancer management. Imaging-based maps used to predict the location of the cancer will be integrated with procedures already in use in the clinic. This will allow physicians to use imaging to full advantage.

For example, a 3D ultrasound-guided prostate biopsy system developed by Dr. Aaron Fenster at Robarts Research Institute already makes use of MRI data to help guide the biopsy needle. Localization of biopsy targets could be improved even further by incorporating information from additional imaging methods.

Similarly, a better way to define the boundaries of prostate cancer could very quickly be applied to radiation treatment. Current treatment strives to deliver different radiation doses to different parts of the prostate depending on the location and extent of the cancer. As Dr. Bauman points out, "the treatment bullets are there; we just need to know where to aim."

Dr. Bauman credits London's Biomedical Imaging Research Centre (BIRC) with efficiently connecting the team to the imaging community city-wide. This has enabled coordinated responses to funding and research opportunities available through organizations such as the Ontario Institute for Cancer Research and the Movember International Prostate Cancer Research Foundation.