2012 Proceedings - International Tissue Elasticity Conference

064 ELASTOGRAPHIC FINDINGS COMPARISON OF CANCEROUS BREAST LESIONS OBSERVED
IN VIVO.
Elisabeth Brusseau 1 , Valérie Detti 1 , Agnès Coulon 2 , Emmanuèle Maissiat 2 ,
Mojgan Devouassoux–Shisheboran 3 , Nawèle Boublay 4 , Loïc Boussel 1,2 , Jérémie Fromageau 5 ,
Nigel Bush 5 , Jeffrey C. Bamber 5 .
1 CREATIS; CNRS UMR5220, Inserm U1044, INSA–Lyon, Université Lyon 1, 7 av. Jean Capelle,
69621 Villeurbanne, FRANCE; 2 Service de Radiologie, 3 Anatomie et Cytologie Pathologiques,
Hospices Civils de Lyon, Hôpital de la Croix–Rousse, 69004 Lyon, FRANCE; 4 Hospices Civils de
Lyon, Pôle Information Médicale Evaluation Recherche, Université Lyon 1, EA 4129, Memory
Research Centre (CMRR), Lyon, FRANCE; 5 Joint Department of Physics, Institute of Cancer
Research and Royal Marsden Hospital, Downs Rd, Sutton, Surrey SM2 5PT, England, UK.
Background and Aims: In previous studies, we reported on the clinical application of our 2D locally
regularized strain estimation method and on the use of the mean Normalized Correlation Coefficient
(NCC) map to locally provide an indication of reliability for strain image interpretation. Different types of
breast lesions were examined, showing great variability in tissue response to compression [1]. In this
study, the analysis is refocused on cancers, comparing lesion characteristics between B–mode and strain
images and considering the available histological details to better appreciate the contribution of
elastography.
Methods: Ten clinical cases of malignant lesions were examined, consisting of five invasive ductal
carcinomas Grade I (IDC I), four with Grade II and one with Grade III. In this two–center study, data were
acquired at the Hôpital de la Croix–Rousse, Lyon, France, with an Ultrasonix (Sonix RP or MDP)
ultrasound scanner equipped with an L14–5W/60 linear probe and at the Royal Marsden Hospital,
London, England, with an Acuson 128XP ultrasound system, working with an L7EF probe.
Radiofrequency echo data were sampled at 40MHz and processed off–line.
Results: The mean correlation coefficient maps associated with the malignant lesions presented a high
mean value that varied between 0.78 and 0.97, with a mean 0.91 over the ten cases considered. In this
study, all the malignant masses examined appeared stiffer than the surrounding tissues. In addition,
when compared to the corresponding lesions in the ultrasound B–mode images, the stiffer regions in the
elastograms frequently appeared significantly larger and with a different overall shape. In Figure 1,
elastography results for two IDC II are presented, supplemented with their histological section. For these
two cases, we can observe that the agreement between the shapes of the lesions in the in vivo images and
those in the histological sections tends to be better for elastography than for B–mode imaging.
Conclusions: The differences observed between B–mode and strain images are consistent with previously
published findings [2,3]. Determination of the biological significance of the complementary information
provided by elastography requires studying the relationship between elastographic and histological
details. For future analysis, particular attention will be paid to considering, as far as is possible, the
histological section of the whole tumor in a plane corresponding to the imaging plane.
References:
[1] Brusseau et al.: Response to Compression of Different Breast Lesions Observed In Vivo with 2D Locally
Regularized Strain Estimation Method. Tenth International Tissue Elasticity Conference, pp. 63, 2011.
[2] Garra et al.: Elastography of Breast Lesions: Initial Clinical Results. Radiology, 202, pp. 79–86, 1997.
[3] Itoh et al.: Breast Disease: Clinical Application of US Elastography for Diagnosis. Radiology, 239, pp. 341–350, 2006.
10%
0.9
5
0.8
0
0.7
Case A (a) (b) (c) Mean NCC: 0.96 (d)
15%
10
0.9
5
0.7
Case B (a) (b)
0
(c) Mean NCC: 0.87
0.5
(d)
Figure 1: Examples of breast lesion deformation under compression for two IDC II. For each case (a) ultrasound
image, (b) strain image, (c) mean NCC map and (d) histological section are shown.
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indicates Presenter