br Along with improved treatment options the importance
Along with improved treatment options, the importance of imaging in the metastatic setting will increase
Survival from primary breast cancer has steadily increased. Still, many women have distant metastases already at the time of diagnosis and quite a few women are diagnosed with a disease that has spread 5 years after diagnosis. The most common metastatic sites are bone, lymph nodes, liver, lung, pleura and brain. Some-times there is a heterogeneity in tumor characteristics between the primary tumor and the metastases or a shift occurs after treatment. The most common imaging method for monitoring metastatic disease is contrast enhanced computed tomography (CT) for thoracic and abdominal metastases and bone metastases in these regions. Nuclear imaging methods such as bone scintigrams are used to further diagnose and map the extent of e.g. bone metas-tases. The current treatment options for metastatic disease includes both cytotoxic and targeted therapies which act differently in the tissues and hence may result in various types of tissue changes. Monitoring treatment response in the metastatic situation chal-lenges the traditional, structural imaging methods such as CT and calls for more functional imaging to enable visualization of for example decreased metabolism rather than decrease in tumor size. In PET, positron-emission- tomography where a radioactive tracer coupled to a metabolite that is consumed preferably by tumor LGlutamine is used, combined with whole-body CT (or MRI) for anatomical correlation, is a strong candidate. The tracers need to be specific enough for breast cancer and initiatives such as HER2-targeted PET have shown promising initial results . We foresee a stronger focus on patients in the metastatic situation and new treatment strategies coming up, leading to more women living longer with their breast cancer. The high costs of using newly developed drugs will drive the exploration of well-working structural and functional imaging methods for monitoring treatment response in order to select the right patient for treatment.
Medical disciplines will be closer integrated for the full benefit of the patient
In addition to the numerous opportunities that we foresee within the field of breast imaging, we also believe that there will be an increased integration between all involved medical disciplines. First, the diagnostic disciplines radiology and pathology are likely to merge to provide a joint foundation on which to base treatment decisions. Second, the diagnostic disciplines will be integrated with the treatment disciplines to improve the continuous evaluation and
optimization of treatment. Third, we may see a more important role for preventive disciplines using knowledge acquired from epide-miological studies of incident breast cancer diagnoses.
Conflicts of interest
FS declares no conflicts of interest. SZ has received speaker's fees and travel support from Siemens Healthcare AG.
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