Ultrasound Elastography and Fibrotic Focus in Breast Cancer: A Comparative Study of Strain Elastography and Shear Wave Elastography

Fibrotic focus (FF) is a histopathological feature associated with poor prognosis in breast cancer. This study evaluated the relationship between FF and ultrasound (US) elastography, a non-invasive imaging method, to assess tissue stiffness and compare the clinical significance of strain elastography (SE) and shear wave elastography (SWE). The data of breast cancer patients who underwent preoperative SE or SWE were retrospectively analyzed. FF was assessed histologically, and medical records were reviewed. Correlations between FF and elastography parameters, as well as associations with clinicopathological features, were analyzed. A total of 109 patients were included, and FF was present in 42 (38.5%) patients. Of the 87 patients who underwent SE, 41 (47.1%) had hard lesions, 45 (51.7%) intermediate lesions, and one (1.1%) a soft lesion. Of the 22 patients who underwent SWE, mean stiffness was 111.9 ± 55.1 kPa, and 14 patients had a mean value of more than 100 kPa. FF was associated with an older age, postmenopausal status, larger tumor size, lymphovascular invasion, and intratumoral inflammation. No significant correlation was found between FF and SE or SWE elastography findings. However, SWE values were significantly lower for tumors exhibiting intratumoral and peritumoral inflammation. Although FF is a marker of tumor aggressiveness, SE and SWE findings were not significantly associated with FF. These results suggest that various tumor microenvironments, such as TIL, may influence measurements of the fibrotic tumor microenvironment using current US elastography techniques.