Canine Mammary Tumors: A Study on 12 Clinical Cases
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Abstract
Introduction: Canine mammary tumors (CMTs) are the most prevalent neoplasms in female dogs, posing a substantial threat to their overall health and quality of life. The present study aimed to investigate the incidence, characteristics, and staging of canine mammary tumors in bitches presented to the Veterinary Teaching Hospital, University of Jos, Nigeria.
Materials and methods: Data from 12 dogs with CMTs presented to the Veterinary Teaching Hospitals, University of Jos, Nigeria, from 2022 to 2023, including age and breed of the bitches, affected gland(s), size, weight, consistency, external appearance of the tumor, and staging were obtained. Data were categorized using the modified World Health Organization’s tumor-nodal involvement-metastasis (TNM) Classification.
Results: Among the 12 CMT cases studied, the findings revealed a high incidence (50%) in elderly dogs (8 years and older), with the Russian Shepherd breed being the most susceptible (50%). The CMTs were predominantly hard, encapsulated masses, measuring 4 to 20 centimeters and weighing 90 to 1000.6 grams. Six cases had a solitary (single) mass within a single gland, and the other half (6) had multiple (more than one) masses located either in a single mammary gland (multifocal) or in multiple (more than one) mammary glands (multicentric). Most of the tumors (67%) were located in the right mammary gland chain, and the inguinal mammary glands were highly susceptible (58%). Stage III tumors were the most prevalent and accounted for 42% of the cases.
Conclusion: The present study highlighted the importance of timely detection and diagnosis of CMTs, with a high prevalence of early-stage tumors (75%). Notably, 50% incidence of CMTs in Russian Shepherds suggested a potential breed predisposition and warrants further investigation.
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References
Zheng HH, Du CT, Yu C, Zhang YZ, Huang RL, Tang XY, et al. Epidemiological investigation of canine mammary tumors in Mainland China between 2017 and 2021. Front Vet Sci. 2022; 9: 843390. DOI: 10.3389/fvets.2022.843390
Tkaczyk-Wlizło A, Kowal K, Śmiech A, and Ślaska B. Occurrence of mammary gland tumours in male dogs and its weak association with development of testicular tumors: A review. J Appl Genet. 2024; 65(1): 137-153. DOI: 10.1007/s13353-023-00818-z
Vazquez E, Lipovka Y, Cervantes-Arias A, Garibay-Escobar A, Haby MM, Queiroga FL, et al. Canine mammary cancer: State of the art and future perspectives. Animals. 2023; 13(19): 3147. DOI: 10.3390/ani13193147
Kaszak I, Ruszczak A, Kanafa S, Kacprzak K, Król M, and Jurka P. Current biomarkers of canine mammary tumours. Acta Vet Scand. 2018; 60(1): 66. DOI: 10.1186/s13028-018-0417-1
Pastor N, Caballé NC, Santella M, Ezquerra LJ, Tarazona R, and Duran E. Epidemiological study of canine mammary tumours: Age, breed, size and malignancy. Austral J Vet Sci. 2018; 50(3): 143-147. Available at: https://www.scielo.cl/pdf/australjvs/v50n3/0719-8132-australjvs-50-03-00143.pdf
Salas Y, Márquez A, Diaz D, and Romero L. Epidemiological study of mammary tumours in female dogs diagnosed during the period 2002-2012: A growing animal health problem. PLoS One. 2015; 10(5): e0127381. DOI: 10.1371/journal.pone.0127381
Cassali GD, Damasceno KA, Bertagnolli AC, Estrela-Lima A, Lavalle GE, Santis GD, et al. Consensus regarding the diagnosis, prognosis and treatment of canine mammary tumours: Benign mixed tumors, carcinomas in mixed tumours and carcinosarcomas. Braz J Vet Pathol. 2017; 10(3): 87-99. Available at: http://bjvp.org.br/wp-content/uploads/2017/11/v10-n3-1.pdf
Benavente MA, Bianchi CP, and Aba MA. Canine mammary tumours: Risk factors, prognosis and treatments. J Vet Adv. 2016; 6(8): 1291-1300. DOI: 10.5455/jva.20160916045115
Horta RS, Lavalle GE, Cunha RM, Moura LL, Araújo RB, and Cassali GD. Influence of surgical technique on overall survival, disease-free interval, and new lesion development interval in dogs with mammary tumours. Adv Breast Cancer Res. 2014; 3(2): 38-46. Available at: https://www.scirp.org/pdf/ABCR_2014041712535344.pdf
Sorenmo KU, Worley DR, and Zappulli V. Tumors of the mammary gland. In: Vail D, Thamm D, Liptak JM, editors. Withrow & MacEwen's small animal clinical oncology. 6th ed. Elsevier, 2019. p. 604-625. Available at: https://www.sciencedirect.com/science/chapter/monograph/abs/pii/B9780323594967000281?via%3Dihub
Dolka I, Czopowicz M, Stopka D, Wojtkowska A, Kaszak I, and Sapierzyński R. Risk factor analysis and clinicopathological characteristics of female dogs with mammary tumors from a single-center retrospective study in Poland. Sci Rep. 2024; 14(1): 5569. DOI: 10.1038/s41598-024-56194-z
Bindu PH, Kumar BP, Prasad VD, and Prasad BC. Incidence of mammary tumors in dogs: A review of 20 cases. Pharm Innov J. 2023; SP-12(12): 900-902. Available at: https://www.thepharmajournal.com/archives/2023/vol12issue12S/PartL/S-12-11-180-558.pdf
Moe L. Population-based incidence of mammary tumors in some dog breeds. J Reprod Fertil Suppl. 2001; 57: 439-443. Available at: https://pubmed.ncbi.nlm.nih.gov/11787188/
Jing Z, Feng J, and Jin H. Epidemiological investigation and surgical treatment of canine mammary tumours in Dalian, China, from 2019 to 2023. PLoS One. 2024; 19(11): e0314292. DOI: 10.1371/journal.pone.0314292
Ariyarathna H, De Silva N, Aberdein D, Kodikara D, Jayasinghe M, Adikari R, et al. Clinicopathological diversity of canine mammary gland tumours in Sri Lanka: A one-year survey on cases presented to two veterinary practices. Vet Sci. 2018; 5(2): 46. DOI: 10.3390/vetsci5020046
Mello SS, Modesto TC, Milken VMF, and Ronchi AAM. Epidemiological and clinicopathological characteristics of mammary tumors in female dogs: A retrospective analysis. Austral J Vet Sci. 2025; 57: e5708. DOI: 10.4206/ajvs.57.08
Ferreira T, Miranda M, Pinto-Leite R, Mano JF, Medeiros R, Oliveira P, et al. Integrated study of canine mammary tumors histopathology, immunohistochemistry, and cytogenetic findings. Vet Sci. 2024; 11(9): 409. DOI: 10.3390/vetsci11090409
Sruthi S, Prasanna K, George A, Sajitha I, Sudheesh S, Varuna P, et al. Mammary tumours in dogs: Age, breed, gender, rearing, and diet factors. Indian Vet J. 2024; 101(2): 34-38. DOI: 10.62757/iva.2024.101.2.34-38