Successful diagnosis and surgical management of a sertoli cell tumor in a mixed breed male dog

Introduction

Testicular tumors are increasingly common in veterinary medicine (Foster, 2012) [2,3] . The dynamics of oncological cases was multimodal the predisposing factors includes environmental changes and genetic traits (Grieco et al., 2008; Nodtvedt et al., 2011) [4,5,10,11] . Testicular tumours can be divided into 2 main categories: stromal sex cord tumors and germ cell tumors. In the first category, we include sertolinoma and leydig cell tumors, the latter being considered the most common testicular tumor in canids, rats and mice (Creasy et al., 2012; Kudo et al., 2019) [1,2,6,7] . Sertoli cell tumors, also known as sustentacular cell tumors arise from the supporting cells of the seminiferous tubules in testis (Gopinath et al., 2009; MacLachlan et al., 2002) [3,8] ) (Grieco et al., 2008; Morrison, 2002) [4,9] . Approximately one third of dogs with sertoli cell tumor will manifest signs of apparent hyperestrogenism, characterized by any combination of feminization, gynecomastia, and atrophy of the contralateral testicle, squamous metaplasia within the prostate gland, symmetrical alopecia and bone marrow atrophy. The clinical manifestations may vary between animal to animal. The incidence of feminization increase from approximately 15% with scrotally located sertoli cell tumors to 70% in abdominally located sertoli cell tumors. The first manifestations of a functional Sertoli cell tumor are usually changes in the skin and hair coat. The skin is usually hyperpigmented and the hair is often easily epilated. Marked squamous metaplasia of the epithelial lining of the ducts and glands of the prostate can lead to glandular obstruction with secondary cyst formation.

Case history and clinical examination

An eight years old male mixed breed dog was presented to SAC, OP, OG Unit of Veterinary Clinical Complex, Veterinary College and Research Institute, Salem, TANUVAS, Tamil Nadu with the complaint of abnormal, large pendulous mass hanging from the inguinal region for the past two months along with alopecia and animal had treatment for the same through nearby veterinary physician. Clinical examination of the mass revealed firm right side testicular mass not showed any pain on palpation with hyperpigmented skin (Fig. 1). Further, ultrasonographic examination revealed disrupted testicular margins, mixed/heterogeneous echotexture (Fig. 2) suggestive of testicular tumor of sertoli cell origin.

Surgical management and discussion

Animal was subjected to surgical resection of testicular tumor affected testis and healthy testis as per the standard surgical procedure (Fig. 3) under general anaesthetic protocol which includes premedication with inj. Atropine sulphate 0.1 % @ 0.04 mg/kg -1 (Atropin-Vet, Doctor's Life Science India Ltd., Andhrapradesh, India) subcutaneously, Inj. Xylazine hydrochloride 2% @ 1 mg/kg -1 (Xylaxine, Indian Immunologicals Ltd, Hyderabad, India) intramuscularly and induced with Ketamine hydrochloride -5 mg/kg -1 (Ketmin-50, Themis Medicare Ltd., Uttarakhand, India), Diazepam -0.5 mg/kg -1 (Lori, Neon Laboratories Ltd., Mumbai, India) cocktail and maintained with ketamine and diazepam cocktail. Post-operative wound management was carried out as per the standard procedure. Resected testicular mass was subjected to histopathological examination which confirmed testicular tumor of sertoli cell origin (Fig. 4). Based on the gross pathology, ultrasonography and histopathology this case was diagnosed as a sertoli cell tumor. Primary testicular tumors are the most prevalent neoplasms in male dogs, accounting for approximately 90% of all tumors affecting the male genitalia (Liao et al., 2009) [7,8] . The Sertoli cell tumor is one of the three main testicular tumors in dogs. Sertoli cell tumors occur more often in cryptorchid animals (Botelho et al., 2014) [1] where in the current case report it was a sertoli cell tumor with descended scrotal testicle. Testicular tumor of sertoli cell origin has a range of clinical signs related to the hormonal derangement namely symmetrical alopecia, gynaecomastia, anaemia, feminization associated with hyperestrogenism, contralateral testicular atrophy squamous metaplasia within the prostate gland (Gopinath et al., 2009; MacLachlan and Kennedy, 2002; Morrison 2008) [3,4,8,9] where as in this case report animal showed only the enlarged and firm testicular structure, prostate gland was normal in terms of size, symmetry and texture without the other clinical signs described in the previous report. Sertoli cell tumors with feminization syndrome due to excessive oestrogen production. Hyperestrogenism disrupts the hypothalamic-pituitary-gonadal (HPG) axis, cause reduction of testosterone production, atrophy of sebaceous glands and impaired spermatogenesis (Herzog et al., 2023, Welle, 2023) [6,12] . These systemic effects impact the overall health status and well-being of the animals.

Conclusion

This case report highlights the importance of ultrasonography and histopathology to arrive a diagnosis and to go with surgical management to safeguard the wellbeing of the affected animals.

Acknowledgement

AcknowledgementThe authors are thankful to The Dean, Veterinary College and Research Institute, Salem, Director of Clinics, TANUVAS and The Associate Professor and Head, Veterinary Clinical Complex, VCRI, Salem for the facilities provided to carry out the work.

References

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