PSA including free PSA (Serum (s), frozen)

For the exact target request please use the wording "PSA and free PSA" if free PSA and the PSA quotient are to be added in any case - irrespective of the PSA result.
Subsequent requests regarding free PSA cannot be carried out for reasons of stability. Patients receiving high doses of biotin (> 5 mg / day) should be sampled at least 8 hours after the last application, as high levels of biotin may interfere with the test system.

In the case of levels in the grey area between 4 - 10 ng, the formation of a free PSA / total PSA ratio is recommended for a possible differentiation between a benign prostatic hypertrophy and a malignant tumour.