JCO Editorial (re: Ontario/Pritchard et al) [18F]Fluorodeoxyglucose Positron Emission Tomography–Computed Tomography in Breast Cancer: When… and When Not?

[18F]Fluorodeoxyglucose Positron Emission Tomography–Computed Tomography in Breast Cancer: When… and When Not?

"....It has taken a relatively long time to generate the data needed to guide appropriate use of FDG PET/CT for breast cancer for all phases of the disease. The task is still not quite complete but is propelled by studies such as Pritchard et al.⁶ We hope that the approach for directing new imaging procedures into clinical practice will continue to improve and be ready when the next imaging breakthrough emerges."

"Diagnostic imaging plays an important role in the care of patients with breast cancer and is used for breast cancer detection, diagnosis, staging, and therapeutic response evaluation.¹ Advances in imaging technology, especially relatively newer technologies such as magnetic resonance imaging (MRI) and positron emission tomography without or with integrated computed tomography (PET or PET/CT) provide powerful diagnostic tools, but also generate questions and controversy regarding where and when to use these new modalities. Early studies of new imaging approaches most often come from centers that are scientifically invested in the development of the technology. Typically, small and highly selected patient populations are evaluated, and these preliminary studies often indicate excellent diagnostic performance. Later on, when large multicenter trials are performed with more clinically representative patient populations, the new test invariably performs less well. Nevertheless, the excitement surrounding early results from a new imaging technology and the increasing public access to these early results fuel the desire by patients for access to new forms of diagnostic imaging. Physicians and patients share the wish for diagnostic certainty in excluding cancer spread at the time of diagnosis and may reason that a purely diagnostic procedure, even if untested, can do no harm. These factors, combined with the challenge and expense of carrying out larger scale diagnostic imaging trials, can lead to the early adoption of new imaging studies into clinical practice, often before their performance and optimal use have been fully determined. However, ......."

abstract: Prospective Study of 2-[18F]Fluorodeoxyglucose Positron Emission Tomography in the Assessment of Regional Nodal Spread of Disease in Patients With Breast Cancer: An Ontario Clinical Oncology Group Study

Prospective Study of 2-[18F]Fluorodeoxyglucose Positron Emission Tomography in the Assessment of Regional Nodal Spread of Disease in Patients With Breast Cancer: An Ontario Clinical Oncology Group Study

 Purpose 2-[¹⁸F]fluorodeoxyglucose (FDG) positron emission tomography (PET) is potentially useful in assessing lymph nodes and detecting distant metastases in women with primary breast cancer.


Conclusion
FDG-PET is not sufficiently sensitive to detect positive axillary lymph nodes, nor is it sufficiently specific to appropriately identify distant metastases. However, the very high positive predictive value (96%) suggests that PET when positive is indicative of disease in axillary nodes, which may influence surgical care.