Fig. 1

^99mTc-RWY SPECT/CT imaging of a 52-year-old woman (patient 1#) with clinical stage II breast cancer in the left breast and the expression level and the clinical significance of integrin α6 in breast cancer. a, b Transverse, c, d coronal, and e, f sagittal plane CT and SPECT/CT. SPECT/CT images of the chest obtained 0.5 h p.i. displayed intense ^99mTc-RWY accumulation in the cancer tissue in the left breast (white arrow). g Hematoxylin–eosin (HE) staining confirmed the presence of tumor cells in the section indicated by the white arrow. Scale bar, 100 µm. h Immunohistochemical staining indicated high integrin α6 expression in the area with high radioactivity accumulation. We also tested the expression and prognostic significance of integrin α6 in breast cancer patients. Scale bar, 100 µm. i A representative image showed varied integrin α6 expression between the breast cancer tissue and the adjacent normal tissue. j The integrin α6 was expressed at a higher level in breast cancer tissues than that in adjacent normal tissues. Ninety-two breast cancer tissues and their adjacent normal tissues were analyzed. The statistical analysis was performed using the paired t test, ***p < 0.001. k, l High integrin α6 expression (Immunoreactive score (IRS) > 4.0) correlated with poor prognosis. Patients were divided into two groups (low and high) based on their levels of integrin α6 expression with IRS = 4.0 as the cutoff value. Note that even in the low group, the breast cancer tissues still expressed a higher level of integrin α6 than the corresponding adjacent normal tissues. Kaplan–Meier plots showed significant differences in survival between the two groups. High integrin α6 expression correlated with poor prognosis for overall survival k and disease-free survival l in these patients. n number of patients, M median months of survival