• In all cases with adequate tissue, an initial Congo red stain is performed before mass spectrometry testing to confirm positivity and pattern of amyloid deposition can be considered when interpreting mass spectrometry results.
• In some instances, per pathologist discretion, a different initial Congo red stain may be performed using SS2PC / Special Stain, Group II, Other
• If the stain is negative for amyloid, then this test will not be performed
• If the stain is positive for amyloid, this test will be performed

Definitive identification of amyloid proteins

This test should only be ordered on patients in whom a primary diagnosis has already been established

• Testing can only be performed on FFPE tissue blocks
• Do not send fixed tissue slides 

Formalin-fixed paraffin-embedded (FFPE) tissue block

B5-fixed paraffin-embedded (FFPE) tissue block

• Preliminary pathology report and history are required
• A brief explanatory note or consultative letter is also recommended

Ambient (preferred)

Refrigerated (OK)

• Fixed tissue slides
• Wet/frozen tissue
• Cytological smears
• Nonformalin fixed tissue
• Non paraffin-embedded tissue

Histological stain/Liquid chromatography-tandem mass spectrometry (LC-MS/MS)

An interpretative report will be provided