Iranian Journal of Veterinary Surgery

Iranian Journal of Veterinary Surgery

Unexpected Relocation of a Cryptorchid Testis due to hCG Administration in an Adult Male Cat

Document Type : Clinical Report

Authors
1 DVM student, Faculty of Veterinary Medicine, Urmia University, Urmia, Iran.
2 DVSc Candidate, Department of Surgery and Diagnostic Imaging, Faculty of Veterinary Medicine, Urmia University, Urmia, Iran.
3 Department of Surgery and Diagnostic Imaging, Faculty of Veterinary Medicine, Urmia University, Urmia, Iran.
4 Department of Pathobiology, Faculty of Veterinary Medicine, Urmia University, Urmia, Iran.
5 Department of Internal Medicine and Clinical Pathology, Faculty of Veterinary Medicine, Urmia University, Urmia, Iran.
6 Department of Theriogenology, Faculty of Veterinary Medicine, Urmia University, Urmia, Iran.
7 Resident of Veterinary Radiology, Department of Surgery and Radiology, Faculty of Veterinary Medicine, University of Tehran, Tehran, Iran.
Abstract
This case report describes the successful diagnosis and surgical management of unilateral cryptorchidism in an adult male domestic shorthair cat with a non-palpable, ultrasonographically occult testis. Initial ultrasonography failed to localize the retained testis. Endocrine testing revealed a baseline testosterone of 91.10 ng/dL, which rose to 298.25 ng/dL four hours after human chorionic gonadotropin (hCG) stimulation, confirming viable testicular tissue. Non-contrast CT subsequently localized the testis to the right inguinal/subcutaneous region. Thirty-one days later, the cat underwent a targeted inguinal approach for removal of the retained testis and concurrent castration of the contralateral scrotal testis. Intraoperatively, the testis was found more caudal than where computed tomography (CT) indicated before. The histopathological analysis of cryptorchid testes reveals significant changes, such as atrophy, reduced diameter of the seminiferous tubules, and absence of spermatogonia. The case supports a stepwise diagnostic pathway (palpation, ultrasonography, hCG stimulation, and CT when needed) to combine functional and anatomic data for precise surgical planning. The CT should be used judiciously due to radiation and anesthesia concerns. Notably, the observed caudal shift of the retained testis between diagnostic hCG administration and surgery suggests that some degree of canalicular mobility may persist in adult cats, underscoring the importance of minimizing the time between imaging and surgical intervention when endocrine stimulation is used.
Keywords
Subjects

  1. Hutson JM. Cryptorchidism and Hypospadias. In: Feingold KR. South Dartmouth (MA): MDText.com Inc.; 2000. Available at: https://www.ncbi.nlm.nih.gov/books/NBK279106/. Accessed 14 Dec 2022.
  2. Ivell R, Hartung S. The molecular basis of cryptorchidism. Molecular Human Reproduction. 2003; 9(4): 175-181. doi: 10.1093/molehr/gag025
  3. Karasu A, Kuşcu Y, Kayıkcı C, Gençcelep M, Kavas B, Ekin M. Evaluation of cryptorchidism in cats and dogs. Turkish Journal of Veterinary Research. 2024; 8(1): 81-87. doi: 10.47748/tjvr.1440967
  4. Spangenberg C. Canine cryptorchidism: a concise review of its origin, diagnosis and treatment. Biology, Engineering, Medicine and Science Reports. 2021; 7(1): 1-3. doi: 10.5530/bems.7.1.1
  5. Shahin M. A case report on surgical management of unilateral cryp-torchidism in a persian cat [Undergraduate Thesis]. Chattogram Veterinary and Animal Science University: Bangladesh. 2023. doi: 10.13140/RG.2.2.28047.60324
  6. Yates D, Hayes G, Heffernan M, Beynon R. Incidence of cryptorchidism in dogs and cats. Veterinary Record. 2003; 152(16): 502-504. doi: 10.1136/vr.152.16.502
  7. Villalobos-Gomez J, Del-Angel-Caraza J, Tapia-Araya A, Brandao F, Hernández-López CA, Martínez-Gomariz F, Botero-Crespo CE, Properzi R. A retrospective study of laparoscopic cryptorchidectomy in 19 cats with intra-abdominal testes. Animals. 2023; 13(1): 181. doi: 10.3390/ani13010181
  8. Memon M, Tibary A. Canine and feline cryptorchidism. In: Recent Advances in Small Animal Reproduction. Concannon PW, England G, Verstegen J, Eds. International Veterinary Information Service, Ithaca, New York, USA. 2001.
  9. Miyoshi N, Yasuda N, Kamimura Y, Shinozaki M, Shimizu T. Teratoma in a feline unilateral cryptorchid testis. Veterinary Pathology. 2001; 38(6): 729-730. doi: 10.1354/vp.38-6-729
  10. Oliveira EL, da Costa AL, Borges MF, Nemer VC, Baldissera RA, Vasconcelos M, Pereira KH, Schimming BC. Unilateral renal agenesis in Chilean-flamingo (Phoenicopterus chilensis). Acta Scientiae Veterinariae. 2020; 48. doi: 10.22456/1679-9216.100607
  11. Cho SE, Fudge JM, Kim S, Page B, Yu D. Cryptorchidism in dogs and cats presented for elective gonadectomy: a descriptive cohort study of 306 animals treated between 2018 and 2023. Topics in Companion Animal Medicine. 2025; 65: 100961. doi: 10.1016/j.tcam.2025.100961
  12. Spada S, De Felice D, Calabria A, Carletti F, Nogueira Aires LP, Vignoli M, Rosto M, Russo M. Computed tomography assessment of retained testes in dogs. Animals. 2025; 15(10): 1439. doi: 10.3390/ani15101439
  13. Felumlee AE, Reichle JK, Hecht S, Penninck D, Zekas L, Dietze Yeager A, Goggin JM, Lowry J. Use of ultrasound to locate retained testes in dogs and cats. Veterinary Radiology and Ultrasound. 2012; 53(5): 581-585. doi: 10.1111/j.1740-8261.2011.01943.x
  14. Balogh O, Berger A, Pieńkowska-Schelling A, Willmitzer F, Grest P, Janett F, Schelling C, Reichler IM. 37, X/38, XY mosaicism in a cryptorchid Bengal cat with Müllerian duct remnants. Sexual Development. 2016; 9(6): 327-332. doi: 10.1159/000443233
  15. Nagumo T, Yoshii R, Uzuka Y, Hoshino Y, Nakata K, Katayama M, Yamasaki M. Computed tomographic characteristics of testicular teratoma in a cat. Veterinary Radiology and Ultrasound. 2024; 65(5): 496-500. doi: 10.1111/vru.13380
  16. Colenbrander B, Van Straaten HW, Wensing CJ. Gonadotrophic hormones and testicular descent. Archives of Andrology. 1978; 1(2): 131-137. doi: 10.3109/01485017808988329
  17. Memon MA. Common causes of male dog infertility. Theriogenology. 2007; 68(3): 322-328. doi: 10.1016/j.theriogenology.2007.04.025
  18. Bergh A, Söder O. Studies of cryptorchidism in experimental animal models. Acta Paediatrica. 2007; 96(5): 617-621. doi: 10.1111/j.1651-2227.2007.00295.x
  19. Johnson AK. Normal feline reproduction: the tom. Journal of Feline Medicine and Surgery. 2022; 24(3): 212-220. doi: 10.1177/1098612X221079707
  20. Backus R. Plasma oestrogen changes in adult male cats after orchiectomy, body-weight gain and low-dosage oestradiol administration. British Journal of Nutrition. 2011; 106(S1): S15-18. doi: 10.1017/S0007114511001796
  21. Kolon TF, Patel RP, Huff DS. Cryptorchidism: diagnosis, treatment, and long-term prognosis. Urologic Clinics. 2004; 31(3): 469-480. doi: 10.1016/j.ucl.2004.04.009


Articles in Press, Corrected Proof
Available Online from 11 May 2026

  • Receive Date 05 January 2026
  • Revise Date 25 February 2026
  • Accept Date 11 May 2026
  • First Publish Date 11 May 2026