text: The diagnostic study of choice in<unk>  amyloidosis is tissue biopsy of the affected organ. Congo Red staining will show apple green birefringence of the tissue sample under polarized light, and subtyping of light chains (for light chain amyloidosis) can be done via mass spectrometry. Bone marrow biopsy and organ-specific laboratory measurements are also important ancillary tests.
option_0: Primary amyloidosis diagnostic study of choice
option_1: Secondary amyloidosis diagnostic study of choice
option_2: Familial amyloidosis diagnostic study of choice
option_3: Cardiac amyloidosis diagnostic study of choice
option_4: POEMS syndrome other diagnostic studies
option_5: Primary amyloidosis other imaging findings
option_6: Secondary amyloidosis other imaging findings
option_7: Thin basement membrane disease diagnostic study of choice