The value of the AgNOR staining method in identifying carcinoma in situ testis

An early and reliable diagnosis is necessary in order to have the chance of a curative therapy of Carcinoma in situ testis (Cis). Forty-six testicular biopsies were investigated to assess the value of the AgNOR staining method in comparison to placental alkaline phosphatase (PLAP) immunostaining. Both methods provided corresponding results and identical tumor cells were recognized in serial sections. The mean AgNOR counts per nucleus were 26.86 (19-52, SD: 2.68) for CIS cells, 8.18 (5-14, SD: 2.20) for spermatogonia and 12.96 (9-18, SD: 2.44) for Sertoli cells, without the counts overlapping within these three groups. Even single CIS cells are easily and reliably recognizable by their typical AgNOR pattern and their high AgNOR count per nucleus. The independent estimation of 9 testicular biopsies with the AgNOR staining method and the PLAP immunostaining correspondingly revealed 7 biopsies with CIS. Two biopsies lacked tumor cells. The AgNOR staining method can be recommended as an additional diagnostic tool in identifying CIS, because of the short and convenient staining procedure, low costs and the applicability on formalin-fixed and paraffin-embedded material.