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Affiniti. Understands your everyday. The new Philips Affiniti ultrasound system. It understands your everyday. www.philips.com/affiniti To provide the best care for your patients, you need tools that go beyond your expectations. The Philips Affiniti ultrasound system delivers the right balance of elegance and precision engineering. Its exceptional image quality gives you the results you need to stay ahead. And with easy-to-use tools such as image fusion for targeted prostate biopsies, it all adds up to a breakthrough in user-focused, patient-focused care. Philips Affiniti brings high-quality imaging to your practice. www.healthcare-in-europe.com 23 EH @ ECR Elastography: using the entire arsenal Report: Mélisande Rouger ‘When we talk about elastography, we realise there’s still a confusion surrounding its key concepts,’ said Dr Sergi Ganau Macias, a senior breast radiologist at UDIAT-Parc Tauli Corporation in Sabadell, Barcelona. Simply put, it aims at imaging tissue stiffness, which provides additional and clinically relevant information in a non-invasive, non-irradiating way. Soft and flexible lesions are considered benign, whereas rigidity or stiffness is often an indicator of malignancy. ‘In that sense, elastography is truly a substitute for breast palpation. The elastogram will appear next to the B-mode image and show different degrees of stiffness,’ said Ganau, who has used elastography for almost a decade. Mapping stiffness can either be estimated from the analysis of tis- sue strain under a stress or through shear wave imaging. With strain elastography the radiol- ogist applies the transducer and com- presses the breast; the applied pres- sure distorts the breast and lesion to be observed. When the tissue returns to its normal place and shape, the user can assess the elastic modulus. Results are qualitative and can only be meas- ured semi-quantitatively with different ratios or with a colour scale. On the contrary, shear wave or tran- sient elastography enables the user to measure and quantify lesion stiffness without compression, by assessing wave propagation. The technique pro- vides many benefits. It adds value to B-mode ultrasound and is particularly useful in apparently negative ultra- sound studies with uncertain clinical or mammographic findings. It can also be used in case of doubt to characterise small size hypo-anechoic lesions (solid or cystic) and iso/hypo- echoic lesions (fat lobules and/or solid lesions). Elastography can bring additional sensitivity and/or specific- ity to B-mode especially in type 3 or 4a lesions, and may help to monitor neoadjuvant treatment when this is not possible with magnetic resonance, or when MR is not available. Last, but not least, elastography can help to diminish axilar fine needle punc- tion aspiration (PAAF) false negatives. ‘Elastography nicely complements B-mode imaging and enables to pre- cise indications for biopsy,’ Ganau added. Some studies have shown that elastography limits recourse to biopsy and significantly reduces the number of benign breast biopsy diagnoses (http://www.ncbi.nlm.nih.gov/pmc/ articles/PMC3558110/, Breast elastog- raphy: A literature review, A Goddi, M Bonardi and S Alessic). However, despite its high specificity and slight correlation with tumoural phenotypes, the technique will never be a substitute for biopsy, Ganau emphasised. ‘I think a significant downside with elastography is the wide variability between the different models offered by the industry. This versatility complicates the conduct of multicentre trials, which would bring vital and much needed evidence regarding elastography’s indications and uses,’ Ganau explained. In addition, cut-off points remain difficult to establish in the case of shear wave elastography. ‘Which one is the ideal cut-off point? When we search for sensitivity and use a low cut-off point, we will find more can- cers and trigger more negative biop- sies; but when we use a high cut-off point, we end up with the opposite problem, i.e. a low cancer detection rate,’ he said. False positives may be due to the presence of calcium, fibromatous component or mucinous carcinoma. Ganau recommends using the whole ultrasound arsenal because techniques are complementary. ‘It’s very important to use Doppler, B-mode imaging, harmonics and elas- tography – in a word,’ he concluded, ‘everything we have to detect cancer as early as possible.’ Although breast elastography entered clinical practice many years ago, a large number of breast radiologists are still unaware of its benefits and have not become familiar with its principles. A session during the last Spanish Breast Congress aimed to improve knowledge of this technique. A specialist in breast pathology and gynaecology Sergi Ganau Macias is a senior radiologist at UDIAT-Parc Tauli Corporation in Sabadell, Barcelona. With over a decade’s experience in the use of elastography he has authored many publications and delivered many talks on this subject.

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