PSA Dynamics traditionally evaluated with an inadequate formula

The PSA doubling time is usually calculated from measured PSA values with an inadequate formula that tacitly assumes the absence of that process, which it is supposed to reveal. We present a modified calculational procedure which is optimized to unveil a weak second exponential process in the presence of a strong first one, using early screening data. The notion of Break Even Time (BET) indicates the stages of the processes.