ADA and cancer: Recently it was proposed that analysis of acetyl amantadine (AcAm) in urine could serve as a diagnostic tool to measure the spermidine/spermine N1-acetyltransferase (SSAT) activity.234 The ADA derivative in question is exclusively a product of the metabolism of amantadine (Am) upon catalysis with SSAT, which in turn is known as a biomarker for multiple aggressive cancers.