Table 4.

Methods, results, advantages and potential limitations of reported previous studies to evaluate metastasis involvement in breast cancer and the present study

Reference First author, year	Methods	Positive samples for metastatic breast cancer	Samples with adequate number of tumor cells for receptor analysis	Potential limitations
J. F. Hilton, 2011 [14]	CT-guided bone biopsy	21/39(52.5%)	19/39(48.8%)	Cannot confirm the location for tumors at the early stage
Wei Guo,2018 [6]	PET/CT guided biopsy	46/54(85.2%)	23/46(50%)	More expensive and less equipment
This study	SPECT/CT guided bone biopsy	34/39(69%)	34/34(100%)	99mTc-MDP is not a specific tracer for metastatic disease