Immunohistochemical prostatic acid phosphatase level as a prognostic factor of prostatic carcinoma.

To determine whether prostatic acid phosphatase (PAP) immunoreactivity in prostatic adenocarcinoma is a reliable prognostic factor, the PAP immunohistochemical distribution has been examined in 78 prostatic carcinoma cases. The intensity of PAP immunostaining was graded from 0 to 2, and the scores of the primary and the secondary staining patterns were added to assess the extent of the PAP expression in needle biopsy specimens. As a result, a higher cancer-specific survival rate was observed in patients showing a greater PAP immunostaining (P less than 0.01). Further, a multivariate analysis was made of possible prognostic factors (age, stage, Gleason score, serum PAP, PAP-immunostaining score, and the initial treatment) to estimate the extent of their impact on cancer-specific survival. Results have confirmed that the difference in PAP immunoreactivity is an excellent, independent prognostic factor for prostatic carcinoma.