We quantified an exogenous cancer biomarker, Acetyl amantadine (AcAm), directly from urine solution using surface enhanced Raman spectroscopy (SERS). SERS was used for the detection of AcAm using a commercial Raman substrate after beta-cyclodextrin encapsulation for capture of the analyte. We achieved a detection limit of 1 ng mL⁻¹ of AcAm in the mock urine in the absence of steroids without extraction or other pre-treatment methods required. With levels of corticosterone typical of urine, the limit of detection was 30 times higher. Since the approach works directly from samples containing the high concentrations of salts and organic co-solutes normal to urine, it has the potential to reduce cost and speed up processing with respect to methods that require pre-purification. Therefore, this is promising for clinical adoption for early cancer detection, particularly for lung cancer.