Ann Yi MD, PhD, Presenter: Nothing to Disclose

Woo Kyung Moon, Abstract Co-Author: Nothing to Disclose

To evaluate whether the breast cancer stiffness according to the immunohistochemistric (IHC) subtypes is associated with the risk of recurrence in early breast cancer patients.

Between January, 2006 and December, 2009, 164 consecutive women (mean age 50.5 years; range 27 – 78 years) who underwent ultrasound (US), sonoelastography and surgery for clinically T1-2 (mean US size 2.1 mm; range 5 – 40 mm), N0 breast cancers. Prospectively recorded elasticity scores of tumor (EST) were correlated with histopathology including IHC subtypes (luminal [ER+ and/or PR+], HER2 [ER- and PR-, HER2+], triple negative [ER-, PR-, and HER2-]) using Fisher’s exact test. Cox proportional hazards model was used to calculate adjusted hazard ratio (HR) of EST for recurrence after controlling for clinicopathologic variables including age, menopausal status, tumor size, tumor histology, nuclear grade, nodal status, lymphovascular invasion status, resection margin status, surgery type, and adjuvant treatment. Recurrence-free survival (RFS) outcomes estimated by Kaplan-Meier curve were compared between low EST (scores 1,2, and 3) and high EST (scores 4 and 5) groups using log-rank test.

Among 164 patients, 116 (70.7%) had luminal, 14 (8.5%) had HER2, and 34 (20.7%) had triple negative tumors. The mean value of ESTs were significantly different between IHC subtypes (4.22±0.94 in luminal, 3.71±0.99 in HER2, 3.82±0.99 in triple negative; P =.036), whereas recurrence rates were not (2.6% [3/116] in luminal, 14.3% [2/14] in HER2, 5.9% [2/32] in triple negative; P =.108). At multivariate cox analysis, high EST was independently associated with worse RFS outcome (HR, 1.63; P =.032) in luminal subtype, whereas were not in HER2 (HR, 1.36; P=.696) and triple negative (HR, 0.75; P =.677) subtypes. 77 patients with luminal high EST tumors had 1.5 times (log rank, 1.51; P = .022) worse RFS outcome than 39 patients with luminal low EST tumors.

High elasticity score of luminal breast cancer might be a risk factor of recurrence in clinically T1-2, N0 breast cancer patients.

Sonoelastography can be used to determine a subgroup of early breast cancer patients with a high risk of recurrence.

Yi, A, Moon, W, Tumor Stiffness on Sonoelastography and the Risk of Recurrence in Early Breast Cancer Patients.  Radiological Society of North America 2014 Scientific Assembly and Annual Meeting, - ,Chicago IL. http://archive.rsna.org/2014/14006860.html