In 26 (40.6%) cases, 1–40% of neoplastic cells were positive, 6 tumours (9.4%) had 41–60% of positive cells, in 12 (18.8%) tumours, the percentage of positive neoplastic cells was 61–80%, in the next 5 (7.8%) tumours, positive cells accounted for 81–90%, and in the remaining 5 (7.8%) tumours, positive cells accounted for 91–100%.The intensity of expression of POSTN protein in Sertoli cells in 41 tumours, i.e. 64.1%, was weak and moderate in 13 tumours (20.3%). The gene discussed is POSTN; the disease is neoplasm.