Multiple Cutaneous Metastasis of a Malignant Leydig Cell Tumour in a Dog

Ultrasound-Based Technologies for the Evaluation of Testicles in the Dog: Keystones and Breakthroughs

Ultrasonography is a valuable diagnostic tool extensively used in the andrology of human and domestic animals, including dogs. This review aims to provide an overview of various technologies based on ultrasound, from the basic B-Mode ultrasonography to the more recent advancements, such as contrast-enhanced ultrasonography (CEUS) and ultrasound elastography (UEl), all of which are utilized in the evaluation of canine testicles. The review outlines the principles behind each of these technologies and discusses their application in assessing normal and abnormal testicular conditions. B-mode canine testicular ultrasonography primarily focuses on detecting focal lesions but has limitations in terms of objectivity. Other technologies, including Doppler ultrasonography, B-Flow, and CEUS, allow for the characterization of vascular patterns, which could be further measured using specific applications like spectral Doppler or quantitative CEUS. Additionally, ultrasound elastography enables the assessment of parenchyma stiffness both qualitatively and quantitatively. These ultrasound-based technologies play a crucial role in andrology by providing valuable information for evaluating testicular function and integrity, aiding in the identification of pathological conditions that may impact the health and quality of life of male dogs.

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 m; average 66.21 22.42 m) and nuclei (from 9 to 57.6 m; average 23.19 7.10 m) 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.

Canine testicular tumors: An 11-year retrospective study of 358 cases in Moscow Region, Russia

Background and Aim:

Canine testicular tumors are among the most common reproductive tract tumors in male dogs and have been studied in many countries. However, to the best of our knowledge, studies with a large sample size have not been conducted in Russia. This study aimed to provide the latest information on the prevalence of canine testicular tumors in the Veterinary Oncology Scientific Center for Small Animals “Biocontrol” in Moscow, Russia, in 2010-2020 and the characteristics of the affected canine population.

Materials and Methods:

A retrospective review of patients and histological reports was collected and analyzed from 358 dogs with 447 testicular tumors within 11 years.

Results:

The mean age of the affected dogs was 10.4 years, whereas that of dogs with Sertoli cell tumors was 9.4 years p=0.009. This study includes mixed-breed dogs (18.4%), Yorkshire Terriers (8.8%), Labrador Retrievers (7.9%), Golden Retrievers (5.0%), and Fox Terriers (3.4%). The most common tumors were interstitial cell tumors (n=227, 50.8%). In contrast, 107 (23.9%) seminomas, 80 (17.9%) Sertoli cell tumors, 19 (7.4%) mixed germ cell-sex cord-stromal tumors, and 26 (7.6%) testicular tumors developed from cryptorchid testes, which included 16 (61.5%) Sertoli cell tumors, 10 (38.5%) seminomas, and no interstitial cell tumors.

Conclusion:

This study provides baseline information on the prevalence of canine testicular tumors in the described population, including the median age of each tumor type and overrepresented dog breeds. We further found that the most common scrotal testicular tumor was interstitial cell tumor, whereas Sertoli cell tumor was the most common in cryptorchid testicles.

Protocol for the Isolation of Stratum Corneum from Pig Ear Skin: Evaluation of the Trypsin Digestion Conditions

Stratum corneum (SC) represents the outermost layer of the skin, being an effective barrier against the entry of molecules and pathogens. Skin research has given particular focus to SC as it hampers effective drug delivery for cosmetical and therapeutical purposes. Following recommendations to develop alternative models to animals, the SC isolated from skin obtained from medical procedures or from pigs has gained extensive attention. Yet, there is still missing a standard and simple procedure accepted within the scientific community to avoid application of different isolated SC methodologies, a fact that may hamper progress in skin research. Considering this challenge, the present study evaluated different experimental conditions aiming to establish a useful and sustainable solvent-free procedure for the obtention of a realistic SC model. The studied trypsin digestion parameters included concentration, incubation period and temperature. Isolated SC was characterized using histological analysis and calcein’s permeability, after the procedure and during a 6-week storage period. Data recommend trypsin digestion at 4 °C for 20 h as the most effective procedure to isolate SC from pig ear skin. This work contributes to standardize the SC isolation procedure, and to obtain a valuable and reliable SC mimetic model for skin drug development.

Senescence and adiponectin signaling - Studies in canine testis

BACKGROUND

The meaning of senescence for tissue physiological and pathological conditions is poorly known. Based on initial reports especially proteins and mechanisms that regulate this process are necessary to be determinate.

METHODS

The main aim of the study was to investigate the presence of senescent cells in canine testicular tissue (mixed breed testes; n = 60) in relation to adiponectin signaling. In detail, new information on the senescence cell number, as well as senescence and adiponectin signaling mechanisms in cryptorchid and germ cell tumor testes were provided with the use of immunohistochemical and colorimetric analyses.

RESULTS

Comparison of immunohistochemical results, in cryptorchid and tumor testes revealed increased number of senescent cells (p16 and γH2AX markers). Increased expression of adiponectin and adiponectin receptor 1, as well as extracellular signal-activated kinase (ERK1/2) in pathological testes were detected. In addition, decreased cholesterol and increased testosterone levels in tumor testis were found.

CONCLUSION

The present study is the first to demonstrate the presence as well as the differences that exist in senecent cell number in mixed breed dog testes with cryptorchidism and germ cell tumor. Altered expression of adiponectin signaling and ERK1/2 signaling pathways together with altered cholesterol and testosterone levels reflect important senescence role in disturbed functions of canine testis. Moreover, the application of studied here senescence regulating molecules for detection and prevention against pathologies of the male gonad should be furtherly considered.

Malignant Leydig cell tumor in dogs: two cases and a review of the literature

Malignant Leydig cell tumor (MLCT) is a rare testicular tumor in dogs. We report herein 2 dogs with MLCT and cutaneous metastasis. Grossly, marked enlargement and distortion of the involved testes were noted; on cut surface, the parenchyma was completely replaced by neoplastic tissue. In addition, these tumors had extensive necrosis and hemorrhage. Case 1 had a rapidly growing cutaneous mass in the left angle of the mouth; the lesion was well-circumscribed and had an indistinct lobular pattern. Case 2 had multiple cutaneous masses in the dorsal neck region, the thoracic back region, and the right hindlimb. Microscopically, the tumor lobules were composed of oval-to-polyhedral cells with eosinophilic cytoplasm and resembled testicular tumors. By immunohistochemistry, the neoplastic cells in both the testicular and cutaneous tumors were positive for inhibin-alpha and melan A. The mitotic counts of the primary tumors from cases 1 and 2 were 21 and 11 per 10 high-power fields, respectively. Based on these findings, the cases were diagnosed as MLCT with cutaneous metastasis. Ki-67 expression in the neoplastic cells of the 2 cases was higher than in benign Leydig cell tumors. Our findings may be helpful for the diagnosis of canine MLCT.

Leydig cell tumor in an Amur tiger (Panthera tigris altaica)

A 14-year and 8-month-old intact male Amur tiger presented with an enlarged left testis, measuring 5.7 × 5.5 × 4.5 cm. The cut surface was mottled dark red to reddish brown in color. Microscopically, the enlarged left testis comprised round or polygonal neoplastic cells arranged in a diffuse sheet pattern. These neoplastic cells had a hyperchromatic nucleus and an abundant eosinophilic cytoplasm. Immunohistochemically, these neoplastic cells were positive for vimentin, chromogranin A, synaptophysin, melan-A, inhibin-α, and S100 and negative for desmin and WT-1. Based on these morphological and immunohistochemical findings, the tumor was diagnosed as a Leydig cell tumor.