DOES THE EI/B-MODE LENGTH RATIO PREDICT BREAST CANCER

TUMOR GRADE?

Joseph R. Grajo, MD*Cynthia Peterson, MPH, RDMS

Richard G. Barr, MD, PhD

Elastography

• Has shown potential to differentiate benign and malignant breast lesions with high sensitivity and specificity

Elastography Techniques

• This study utilizes compression elastography• Varying methods include– Change in length– Change in area– Color elastography– Strain ratio measurements

• In our lab we choose to use grey scale imaging and length change ratios.

Previous Work• We previously reported a sensitivity of 99%

and specificity of 85% in a multicenter study of 635 biopsy-proven lesions

• Average E/B ratios were 0.76 for benign lesions (range 0.2 to 1.5) and 1.45 for malignant lesions (range 1.0 to 3.1)

Hypothesis

• In reviewing various pathologies from our series, we noticed that more aggressive malignancies demonstrated larger E/B ratios

• We hypothesized that the degree of length change correlates with tumor grade

Methods

• Equipment– Siemens Antares Ultrasound System– Siemens S2000 Ultrasound System– Philips IU22 Ultrasound System

• Simultaneous, side-by-side display of B-mode and elasticity images

• “shadow” or “copy” functions used to measure at same location

Methods• We evaluated 134 malignancies diagnosed in

125 patients referred for ultrasound guided core biopsy utilizing a 10 or 13 Hz probe over a 3 year period.

• Measurements were made at the time of the clinical examination by the Radiologist performing the study.

• Biopsies were subsequently performed with a 14 g Vacuum assisted core needle. FNAs were not included.

Methods

• In patients with pre-malignant or malignant diagnoses, pathology reports were reviewed for staging

• If the tumor was excised, grading was based on the surgical specimen

Methods

• Mean E/B ratio of the tumor and the pathology were recorded for each lesion

• E/B ratio of the tumor was compared to Scharf-Bloom-Richardson (SBR) and intraductal carcinoma grade using Pearson correlation coefficient

Scharf-Bloom-Richardson Grading• Tubule Formation

– > 75% = 1– 10-75% = 2– < 10% = 3

• Nuclear Pleomorphism– Small, uniform cells = 1– Mod inc size/variation = 2– Marked variation = 3

• Mitosis Count– Up to 7 = 1– 8 to 14 = 2– 15 or more = 3

• 3, 4, 5 = Low Grade

• 6 or 7 = Medium Grade

• 8 or 9 = High Grade

Results• Average patient age was 64 years old (range

36-95)• E/B ratios varied from 1.0 to 3.1• Pathology

– Pre cancerous lesions 2– Mucinous/colloid 7– DCIS 13– IDC 101

• Grade 1 30• Grade 2 45• Grade 3 26

– Lobular 11

Average E/B Ratio

Pathology Standard Deviation

1.168 Mucinous/Colloid 0.188

1.344 DCIS 0.353

1.460 IDC 0.40

1.506 Lobular CA 0.482

Results

IDC Results

• E/B ratio as compared to the tumor grade in IDC using one-tailed Pearson correlation coefficient (p < 0.05) was 0.078.

• E/B ratio as compared to the SBR grade in IDC using one-tailed Pearson correlation coefficient (p < 0.05) was significant at 0.040.

Conclusion• In this small study, E/B ratio correlates with

the aggressiveness of breast tumors• In Invasive Ductal Cancers, there is a trend for

increased E/B ratio with tumor grade, which was statistically significant

• Other aspects and characteristics of the EI image may provide additional diagnostic information not yet recognized