Canine testicular tumors: two types of seminomas can be differentiated by immunohistochemistry

Abstract

BackgroundTesticular tumors are the most common genital neoplasms in male dogs, with Leydig cell tumors (LCT), seminomas (SEM), and Sertoli cell tumors (SCT) the most common forms. Human SEM are classified as classical (CSEM) or spermatocytic (SSEM). Intratubular germ cell neoplasia of undifferentiated origin (IGCNU) is another form of human testicular tumor. The aim of this study was to verify that CSEM/SSEM classification is valid in dogs and confirm the existence of canine IGCNU.ResultsTesticular tumors were found in 46% of dogs at necropsy and accounted for 7% of tumors biopsied. The median age of dogs with tumors at necropsy was 10.16 years; median age at positive biopsy was 10.24 years. The most common tumors, in decreasing order, were LCT, mixed tumors, SEM and SCT at necropsy, and SEM, SCT, mixed tumors, LCT, peripheral nerve sheath tumor, and teratoma in the biopsy group. IGCNU was found in 3% of testicles at necropsy and in 3% of biopsy samples. Two dogs had testicular tumor metastasis. Expression of c-KIT was most common in SEM and seminomatous components of mixed tumors. PLAP was mostly expressed in IGCNU, SEM, teratoma, and some mixed tumors. Cytokeratin was mainly expressed in SCT. CD30 expression was low in both groups.ConclusionsThe high tumor incidence at necropsy can be attributed to older age. Tumor incidence in biopsy samples, dog age, and histological classification were consistent with previous studies. The higher incidence of SEM and SCT in the biopsy group probably resulted from the obvious clinical expression of these tumor types. The low incidence of metastasis confirmed the predominance of benign tumors. Low CD30 expression confirmed the low incidence of testicular embryonal carcinoma. Cytokeratin helps differentiate stromal tumors, especially SCT, from germ cell tumors. Histology and c-KIT and PLAP expression indicate that IGCNU exists in dogs. Expression of c-KIT and PLAP confirmed that CSEM and SSEM classification is valid in dogs.

Testicular Neoplasms in Dogs in Rio Grande do Sul, Brazil

“…No presente estudo, os neoplasmas testiculares em cães tiveram frequência de 2,4% quando totalizado biópsias de machos e fêmeas, e 6,4% quando selecionado apenas machos. Em estudos similares, a frequência variou de 2,4% a 27% [1,4,6,9,17].…”

“…A média de idade dos cães afetados no presente estudo foi de 11,1 anos. Dado semelhante foi descrito por diversos pesquisadores [1,4,6,17,18]. Cães criptorquidas com neoplasmas testiculares do presente trabalho apresentaram idade média inferior do que os com testículos localizados na bolsa escrotal, com média de 9,5 anos de idade.…”

Seminoma metastático: descripción histomorfológica

“…Algunos autores han demostrado que con técnicas de inmunohistoquímica es posible caracterizar este tipo de tumores (CIAPUTA et al, 2014;HOHSTETER et al, 2014). Infelizmente, en este estudio no se logró realizar ninguna de estas técnicas por el mal estado de conservación de las muestras.…”

IL‐4 downregulates expression of the target receptor CD30 in neoplastic canine mast cells

“…The mouse anti‐human CD30 monoclonal antibody (mAb) Ber‐H2 (work dilution, 1:20, at 4 °C for 16 h) and a biotinylated goat anti‐mouse IgG were applied in these experiments. Ber‐H2 has been validated for veterinary‐use to detect CD30‐positive activated B‐ and T‐cells as well as CD30‐positive canine neoplastic cells by immunohistochemistry (IHC) . In this study, IHC was performed on formalin‐fixed and paraffin‐embedded tumour sections obtained from 32 patients (Table ) essentially as described .…”