The aims of this study were to investigate the value of sound touch elastography (STE) in predicting axillary
lymph node metastasis (ALNM) in patients with invasive
breast cancer (IBC) and to explore whether
lysyl oxidase (LOX) is correlated with increasing stiffness and promotion of
metastasis in IBC. A total of 142 lesions in 142 patients were assessed by STE. The STE values of IBCs in the two groups were compared and the best cutoff values for diagnosing ALNM determined. Immunohistochemistry was used to detect LOX expression.
Collagen fiber and elastic fiber content was determined by Masson and Weigert elastic fiber staining. Correlation analyses were performed to identify the associations of the data. The optimal cutoff values of Emax (maximum stiffness value of the
tumor) and Smax (maximum stiffness value of the shell) for predicting ALNM of IBC were 94.58 and 148.78 kPa. Immunohistochemistry and Masson and Weigert elastic fiber staining were performed on 67 samples. LOX expression and
collagen volume fraction were significantly higher in the ALNM+ group than in the ALNM- group (p = 0.04 and 0.03), except for elastic fiber content (p = 0.628). Moreover, Emax, Smax and LOX expression were positively correlated with
collagen volume fraction (r = 0.624, 0.512, and 0.533, respectively). Emax and Smax were found to be predictors for ALNM of IBC. STE could serve as a non-invasive method for assessing lymph node status before surgery. Overexpression of LOX and increased
collagen fiber contributed to the increased stiffness in the lesions and
metastases of IBC.