In situ hybridisation using cRNA probes revealed positive, heterogenous BSP staining in all tumour cells from intraductal breast cancer bone metastases (n = 10).50 Furthermore, BSP mRNA expression is significantly higher in breast cancer bone metastases versus non-bone metastases,18 though interpretation is limited by small sample size (n = 6), lack of reported p values, and unknown group distributions. Here, IBSP is linked to neoplasm.