Testicular Germ Cell Tumor in Dogs (Seminoma)
- Occurrence: common
- Location of disease: Abdomen/pelvis
When to visit the vet?
Non-urgent see a veterinarian within 2–3 days
If the condition worsens / symptoms persist, consult a veterinarian.
The most important facts at a glance
Seminomas are tumors that arise from germ cells that normally become sperm. They occur mainly in older, unneutered dogs, but can also affect younger animals in rare cases. The exact causes are unclear, but genetic factors, environmental influences, and hormonal imbalances play a role, particularly the hormone testosterone. An increased risk exists in dogs with cryptorchidism, a condition where the testicles have not descended into the scrotum. Seminomas are locally invasive and can penetrate surrounding tissue, which complicates treatment.
Symptoms include pain on palpation, palpable lumps in the testicle, and pain. Diagnosis begins with a physical examination and may include imaging procedures such as ultrasound or X-ray. A biopsy often confirms the presence of a seminoma. Treatment usually consists of the surgical removal of the affected testicle. In advanced cases, chemotherapy or radiation therapy may be required. The prognosis is good with early diagnosis, while it may be less favorable with advanced spread.
For prevention, castration is recommended, especially in cases of genetic predisposition for testicular tumors or cryptorchidism. Regular veterinary examinations and a healthy lifestyle can further reduce the risk. Research aims to better understand the genetic basis and develop new, less invasive diagnostic and treatment methods that improve the quality of life for affected dogs.
Causes
Seminomas belong to the group of germ cell tumors, which develop from the cells that normally become sperm. These tumors occur mainly in older, unneutered dogs, although they can also occur in younger dogs in rare cases. The exact biological basis for why and how these tumors develop is not yet fully understood. However, it is believed that genetic factors as well as environmental influences may play a role.
An important scientific aspect of seminomas is their ability to be locally invasive. This means that they can invade the surrounding tissue, which makes treatment more complicated. Furthermore, there is evidence that dogs with cryptorchidism – the condition in which one or both testicles have not descended into the scrotum – have an increased risk of developing a seminoma.
The causes for the development of a seminoma can be varied. In addition to genetic predispositions, a hormonal imbalance is also discussed as a potential trigger. In particular, the hormone testosterone could play a role in the development of such tumors, as it affects cell growth in the testicles.
Symptoms
The symptoms of a seminoma can vary greatly and often depend on the progression of the disease. In the early stages, an affected dog may show no symptoms at all, which makes early detection difficult. One of the most common signs is a visible or palpable swelling in the scrotum.
In addition to swelling, affected dogs may show pain or discomfort, especially when walking or sitting. In advanced cases, further symptoms may occur, such as weight loss, loss of appetite, or general weakness. Metastases, i.e., the spread of tumor cells to other parts of the body, can cause additional symptoms depending on which organs are affected.
Therapy
The treatment of a seminoma depends on various factors, including the size and stage of the tumor, as well as the general health of the dog. In most cases, surgical removal of the affected testicle is recommended, a procedure known as orchiectomy. This operation is often the preferred treatment method because it directly removes the tumor.
In some cases, additional treatment may be required, especially if the tumor has metastasized. Here, chemotherapy or radiation therapy may be considered to destroy remaining cancer cells and reduce the risk of recurrence. The choice of treatment method should be made in close consultation with a veterinarian, taking into account the specific needs and conditions of the dog.
Prognosis and follow-up care
The prognosis for dogs with seminomas depends significantly on how early the tumor is detected and treated. With early diagnosis and successful surgical removal, the prognosis is generally good, as these tumors often respond well to treatment and only rarely metastasize.
However, if the tumor is discovered at an advanced stage or has already spread to other parts of the body, the prognosis may be less favorable. In such cases, the survival rate depends heavily on the effectiveness of additional treatments.
Prevention
One of the most effective methods for the prevention of seminomas is the castration of male dogs, especially those with a genetic predisposition for testicular tumors or cryptorchidism. Castration can significantly reduce the risk of tumor development as it decreases testosterone production, a hormone linked to tumor development.
Regular veterinary examinations are also important to detect possible signs of testicular disease early. Dog owners should regularly examine their dogs for unusual swelling or changes in the area of the testicles and consult a veterinarian immediately if they notice anything unusual.
Furthermore, a healthy diet and an active lifestyle can help lower the overall risk of cancer. While there is no absolutely certain method to completely prevent seminomas, these measures can help minimize the risk and promote the dog’s health.
Outlook on current research
Current research on seminomas in dogs is working intensively to better understand the genetic and molecular basis of this type of tumor. Researchers are analyzing genetic markers associated with the development of seminomas to identify potential risk factors. Genetic predispositions could be more common in certain breeds, which could influence future breeding decisions. The identification of such genetic markers could also support the development of more precise diagnostic tests.
Another research focus is on improving diagnostic techniques. Currently, studies are investigating how imaging procedures, such as ultrasound and magnetic resonance imaging (MRI), in combination with advanced laboratory tests, can increase the accuracy of diagnoses. These approaches could make it possible to detect seminomas in early stages, which would significantly improve the prognosis and treatment options.
Regarding treatment, new therapeutic strategies are being explored. This includes the possibility of developing targeted therapies that focus on specific molecular changes in seminomas. Such therapies could be less invasive and have fewer side effects than current standard treatments like surgery and radiation therapy. Clinical trials are investigating the effectiveness of chemotherapeutic agents and immunotherapies designed to stimulate the dog’s immune system to fight tumor cells more effectively.
Another area of research deals with the quality of life of dogs living with seminomas. The goal is to develop better management strategies that not only prolong survival but also improve the quality of life of the animals. These include pain management, nutritional plans, and physical therapies tailored to the individual needs of each dog.
In summary, research on seminomas in dogs is progressing on several levels, from basic genetic research to innovative treatment methods. Advances in this field could not only improve the lives of affected dogs but also provide valuable insights into similar diseases in other animal species and in humans.
Frequently Asked Questions (FAQs)
1. What is a seminoma in dogs?
2. What symptoms can occur in a dog with a seminoma?
3. How is a seminoma diagnosed?
4. What treatment options are available for dogs with a seminoma?
5. Is a seminoma in dogs malignant?
6. Can a neutered dog develop a seminoma?
7. Which dogs are most commonly affected by seminomas?
8. Are there preventive measures against seminomas in dogs?
9. What is the prognosis for dogs with a seminoma?
10. How can I improve the quality of life for my dog with a seminoma?
Literature
- Grieco, V., Riccardi, E., Greppi, G. F., Teruzzi, F., Iermanò, V., & Finazzi, M. (2008). Canine testicular tumours: A study on 232 dogs. Journal of Comparative Pathology, 138(2–3), 86–89. https://doi.org/10.1016/j.jcpa.2007.11.002
- Gazin, A. A., Vatnikov, Y. A., Sturov, N. V., Kulikov, E. V., Grishin, V., Krotova, E. A., Varentsova, A. A., Rodionova, N. Y., Troshina, N. I., Byakhova, V. M., & Lisitskaya, K. V. (2022). Canine testicular tumors: An 11-year retrospective study of 358 cases in Moscow Region, Russia. Veterinary World, 15(2), 483–487. https://doi.org/10.14202/vetworld.2022.483-487
- Hohšteter, M., Artuković, B., Severin, K., Kurilj, A. G., Beck, A., Sostaric-Zuckermann, I.-C., & Grabarević, Ž. (2014). Canine testicular tumors: Two types of seminomas can be differentiated by immunohistochemistry. BMC Veterinary Research, 10, 169. https://doi.org/10.1186/s12917-014-0169-8
- Liao, A. T., Chu, P. Y., Yeh, L. S., Lin, C. T., & Liu, C. H. (2009). A 12-year retrospective study of canine testicular tumors. Journal of Veterinary Medical Science, 71(7), 919–923. https://doi.org/10.1292/jvms.71.919
- Ciaputa, R., Janus-Ziółkowska, I., Żebrowski, K., Nowak, M., Dzimira, S., Piotrowska, A., Ratajczak-Wielgomas, K., Kandefer-Gola, M., & Grieco, V. (2026). Expression of periostin and podoplanin in canine testicular tumours. BMC Veterinary Research, 22, Article 7. https://doi.org/10.1186/s12917-025-05176-y
- Bracco, C., Gloria, A., & Contri, A. (2023). Ultrasound-based technologies for the evaluation of testicles in the dog: Keystones and breakthroughs. Veterinary Sciences, 10(12), 683. https://doi.org/10.3390/vetsci10120683