Technetium-99m-methylene diphosphonate single photon emission computed tomography/computed tomography combined with prostate-specific antigen/free prostate-specific antigen ratio for bone metastasis of prostate cancer

Table 1 Final criteria for diagnosing suspicious lesions

No.	Criteria for diagnosing suspicious lesions
1	Results of two or more imaging techniques were consistent
2	Diagnosis was confirmed by pathological examination after operation or puncture
3	SPECT/CT follow-up review was combined with clinical history and other laboratory tests

SPECT/CT: Single photon emission computed tomography/computed tomography.

Table 2 Operations procedures of enzyme-linked immunosorbent assay

No.	Operations procedures of ELISA
1	Coating: the antigen or antibody solution to be detected was coated on the microporous plate and adsorbed on the pore wall
2	Blocking: a certain concentration of protein (such as bovine serum albumin) was added to block unadsorbed pore walls to avoid non-specific binding
3	Addition of a certain concentration of detection antibody: the detection antibody labeled with enzyme was added to the well, and the antigen or antibody has been adsorbed
4	Wash: the unbound antibody in the hole was absorbed with a buffer solution
5	Addition of substrate: substrate was added to catalyze the reaction by the enzyme to produce a measurable signal
6	Reading plate: the signal is read by the enzyme marker to calculate the concentration of antigen or antibody

ELISA: Enzyme-linked immunosorbent assay.