Page 1 - The Contemporary Role of Conventional Imaging for Staging, Re-staging, and Monitoring Prostate Cancer: Impact on Management

The Contemporary Role of Conventional Imaging for
Staging, Re-staging, and Monitoring Prostate Cancer:

Impact on Management

which are widely used to evaluate metastatic nodal
Imaging in Clinical Practice and bone lesions. Newer technologies such as PSMA
(prostate-specific membrane antigen) or Choline
ecause the natural course of prostate cancer can PET-CT (positron emission tomography-computed
Bvary considerably between patients, accurate and tomography) may be available in research settings but
reliable tools to assess patients and their disease are are not broadly accessible for use in routine practice, as
critical for clinical decision-making. The choice of they are not yet approved by Health Canada. Moreover,
the imaging modality and timing are driven by the despite showing obvious improved accuracy when
ability of the results to inform the management plan. compared with conventional imaging, the clinical
The prostate cancer treatment paradigm continues to impact of these new imaging techniques remains to be
evolve quickly, particularly in patients with advanced determined. Phase 3 clinical trials for new therapeutics
disease, where clinical trial evidence supports changes in CRPC have defined initial metastatic disease and
to the current standard of care in hormone-sensitive progression based on conventional imaging, hence this
and castration-resistant prostate cancer (CRPC). As review will focus on conventional imaging.
clinical decision-making becomes more complex, it is
worthwhile revisiting the role of conventional imaging
and examining the most recent recommendations from Measuring Imaging Performance
leading urology and oncology groups.
he value of a diagnostic tool such as imaging is
This review focuses on the role of conventional imaging Tdependent on its ability to depict the true healthy
at three pivotal points along the prostate cancer care or disease state. Few clinical studies of imaging
continuum that have significant implications for procedures report on the sensitivity and specificity of
patient management: 1) at the time of primary staging the technique based on a strong reference standard
before local therapies; 2) when re-staging is required such as clinical impact or progression. In fact, a
to inform treatment strategies for disease recurrence majority of studies report on detection rates without
before or after androgen deprivation therapy (ADT); reference standard. Therefore, the design of imaging
and 3) during systemic therapy for advanced disease, studies is critical for understanding what the imaging
mainly to evaluate response to therapy. modality tells us about the patient state, and with what
certainty. The comparator arm sets the bar.
Conventional Imaging For example, during primary staging, nodal status
(detected by imaging as abnormal or not) is a key
maging technologies continue to improve in order to factor in determining the treatment plan (clinical
Ibetter depict local disease, lymph node invasion, and impact) and is considered a strong predictor of failure
bone metastasis. However, clinical practice decisions in of primary therapies. Ideally, studies that compare
Canada are still largely based on conventional imaging
modalities such as magnetic resonance imaging (MRI),
computed tomography (CT), and bone scintigraphy, Continued on page 2

Authors
Frédéric Pouliot, MD, PhD, FRCSC Franck Bladou, MD, FRCSC
Associate Professor and Urologist Oncologist Professor of Surgery (Urology) and Oncology, McGill University
Division of Urology Herbert Black Chair in Surgical Oncology
Department of Surgery Chief - Department of Urology
Université Laval Jewish General Hospital, Montreal
CHU de Québec

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