Histology of prostate biopsy samples. Human prostate biopsy samples were processed using the intact biopsy method in 80% methanol followed by paraffin embedding and sectioning. (a) Prostate section processed for immunohistochemistry using PIN4 stain where red indicates racemase and brown indicates p63 and basal keratin. (b) An immediately adjacent section stained with hematoxylin and eosin (H & E). Black arrows indicate prostatic adenocarcinoma and blue arrows indicate benign glands.