Is a biopsy the only way to differentiate between prostatitis and prostate cancer?

Usually: A biopsy is the gold standard to not only confirm cancer but to get information on the aggressiveness of the cancer. In rare cases such as a very high psa and with an enlarged prostate or with bone involvement it may be sufficient to assume a diagnosis of prostate cancer.

PROSTATITIS: I agree that the only way to reliably determine this is a biopsy, but rate of rise of psa andconcomitant symptoms associated with this may be helpful. A test called pca3 may be helpful as well.