Hadi Tadayyon June 11, 2012

 Clinical challenge ◦ High risk for metastasis  Characterized as: ◦ > 5 cm long axis ◦ Skin/chest wall involvement ◦ Lymph node involvement  Tumour grade – a histological feature that is a prognostic indicator and is important for treatment design ◦ Determined from pathological examination of biopsy sample ◦ Higher grade  higher degree of malignancy / poorer prognosis  Our goal: ultrasonically detect variation in tumour grades

 Midband fit, slope, and intercept used to differentiate: ◦ Prostate cancer from benign tumours 1 ◦ Metastic from non-metastatic lymph nodes 2  Acoustic scatterer spacing used to characterize breast lesions as benign or malignant 3 1.Feleppa et al., 2004 IEEE Trans UFFC, 43(4), , (1996) 2.Mamou et al., Ultrasound in Med. & Biol., 37(3), 345–357, (2011) 3.Y. Bige et al., Ultrasonics 44, 211–215, (2006)

 Can LABC tumours be characterized in terms of grade using quantitative ultrasound?  Given: ◦ Retrospective in-vivo clinical breast data (N=43) ◦ A diagnostic ultrasound machine

Tumour ROI 1 cm Normal breast ROI QUS Midband fit (MBF) Slope (SS) Intercept (SI) Scatterer spacing (SAS) GI (N=3) GII (N = 22) GIII (N = 18)  10 MHz fc linear array transducer (Ultrasonix, Canada)  4-7 cm depth  5 MHz 50% bandwidth Normal tissue ROI

 Depth-dependent spectral normalization (reference phantom)  Variable bandwidth linear regression  Discrete depth spectral normalization (reference reflector)  Auto-regressive (AR) spectral estimation and autocorrelation- derived scatterer spacing

Mann-Whitney test: p = 0.032

GI GII GIII NT SAS (mm) 10 um 1 cm

Mean spacing between glandular islands = 200 um 100 um

 A potential method to non-invasively characterize tumour grade was proposed  Scatterer spacing statistically different among tumour grades (ANOVA test & Mann-Whitney test)  Scatterer spacing is linked to spacing between glandular islands  Small sample size for GI ◦ In large population study – 362/1409 = 25% ◦ In our study, 3/43 = 7%  Cannot evaluate classification due to insufficient parameters  Future directions: investigate other QUS parameters

Czarnota Lab, University of Toronto Dr. Czarnota Dr. Omar Falou Mike Papanicolau Sara Iradji Ervis Sofroni Ryerson University Dr. Lauren Wirtzfeld University of Illinois Dr. Michael Oelze CGSD

Increasing risk of metastasis Grade IGrade IIGrade III Total score