Cytology in the diagnosis of neoplastic and non neoplastic testicular diseases in dogs

In the present study, a cytological examination of 144 testicles from 93 do gs, which were castrated in the Clinic for Small Animals, School of Veterin ary Medicine Hannover, was performed. Histopathological examination of the exstirpated testicles, which was performed in ail cases, revealed the follo wing diagnoses: 27x Leydig cell tumor, 8x Sertoli cell tumor, 12x seminoma, 5x combined und other testicular tumors, 19x hypoplasia (extrascrotal test icles), 17x degeneration, 5x chronic orchitis and 9x other non neoplastic a lterations. 42 testicles proved to be histopathologically inconspicuous and made up the control group. Fine needle aspiration (FNA) cytology showed a sensitivity of 90 per cent, a specifity of 97 per cent and a positive predi ctive value of 94 per cent concerning the detection of testicular tumors. F or the imprint technique these statistic values were determined with 87 per cent, 98 per cent and 96 per cent. In respect to the detection of a - cyto logically not differentiable - testicular hypoplasia or degeneration sensit ivity was 84 per cent, specifity was 99 per cent and positive predictive va lue was 97 per cent (FNA) and 86 per cent, 98 per cent and 94 per cent (imp rint technique), respectively. Leydig cell tumors, Sertoli cell tumors and seminomas proved to show characteristic individual features. This made a co rrect tumor typing possible in 100 per cent (FNA) and 95 per cent (imprint technique), respectively, of all cases in which a neoplasia was detected cy tologically. In mixed neoplasias, always only one tumor component could be detected. The cytological detection of chronic inflammatory testicular dise ases proved to be difficult. These results emphasize the diagnostic value o f cytology in the diagnosis of testicular diseases in dogs. Therefore this technique should get more appreciation in this indication.