Nuclear bodies appearance rate in canine testicular Sertoli cell tumor

A number of nuclear bodies (NB) were observed in the canine testicular Sertoli cell tumors (SCT). We statistically examined nineteen cases of canine SCT concerning the NB appearance rate (NBAR), and also examined the NBAR in four cases of the normal testicular Sertoli cells. The mean value of the total number of the NBAR of SCT was significantly higher than that of normal Sertoli cells. The SCT were classified into three groups according to the Nielsen and Lein's histological classification (1974): intratubular SCT without invasion, intratubular SCT with invasion, and diffuse type SCT. The mean value of NBAR of the diffuse type SCT was significantly higher than that of the intratubular SCT with and without invasion, and there was no significant difference between the mean values of NBAR of the latter two groups. The distribution of NBAR of the diffuse type SCT was significantly different from that of the intratubular SCT with and without invasion. On the other hand, the individual differences of NBAR of the diffuse type SCT and the intratubular SCT with invasion was significantly higher than that of the intratubular SCT without invasion. The present study suggests that the increase of NBAR in canine SCT might be correlated with the tumor invasive progression.