Morphological characteristics of testicular interstitial cell tumors in dogs

The study presents an assessment of variability of histological structure, measurement, and comparison of size of the neoplasm obtained by ultrasonographic examination and pathological examination, as well as the morphometric dimensions of nuclei and cytoplasm of testicular interstitial cell tumors in dogs. The study involved 35 dogs with neoplasms of 46 testes, where 11 animals had interstitial cell tumors in both testes. Insignificant differences of the size of these neoplasms were revealed (p > 0.05) using ultrasonography and pathoanatomical measurement methods. Hence, it allows using both methods to assess the size of interstitial cell tumors. In the study, interstitial cell tumor was detected in both testes at once in 50 % of cases in dogs, however, this might be due to specific characteristics of the sample, and further research is required. In the course of scientific work, a morphological study showed the presence of variability in histological structure of interstitial cell tumors, which can lead to incorrect interpretation of the morphological picture and misdiagnosis, e. g. «adipocyte-like» morphology of interstitial cell tumors have morphological similarity to a benign neoplasm from adipose tissue - lipoma. In addition, there was an extremely pronounced difference in size of cytoplasm (from 23.6 to 148.4 µm; average 66.21 ± 22.42 µm) and nuclei (from 9 to 57.6 µm; average 23.19 ± 7.10 µm) in tumor cells. It proves the presence of pronounced anisocytosis and anisokariosis, which should indicate malignancy of the neoplasm, however, testicular interstitial cell tumors extremely rarely metastasize in practice and according to numerous studies.