Mammary gland tumors are the most common tumors in intact female dogs, and about half are malignant. They are hormone dependent, which is why the timing of spaying matters, and they are usually found as a lump on physical examination. The NAVLE focuses on prevention, staging, choosing the right surgery and spotting inflammatory carcinoma, the one form you should not operate on.
Key facts
Mammary gland tumor at a glance- Species and system: dogs (almost always females; very rare in males and in bitches spayed before their first heat); reproductive system and skin.
- Cause: hormone-dependent neoplasia of mammary epithelium and myoepithelium driven by estrogens, progesterone and growth factors. Exogenous progestins or estrogens raise the risk.
- Classic presentation: a 7- to 11-year-old intact bitch with one or more firm nodules near the nipples, often in the caudal glands.
- Behaviour: about 50% benign, 50% malignant. Malignant tumors spread through lymphatics; the most common metastatic sites are the regional lymph nodes, lungs, liver and kidneys.
- Diagnosis: histopathology of the excised tumor. Fine-needle aspiration cannot reliably tell benign from malignant.
- Treatment of choice: surgical excision of every tumor, except inflammatory carcinoma and distant metastatic disease.
- Zoonotic or reportable: no.
What's inside
13 sections in the full guide- Key facts
- How the NAVLE tests this
- Cause and pathophysiology
- Histologic classification and grade
- Clinical signs
- Diagnosis and staging
- Differential diagnoses
- Treatment and management
- Prevention, control and public health
- Prognosis
- Quick review
- Test yourself
- References
The full guide also has 8 tables, 3 figures, 3 self-test questions and 19 references, available to NAVLE members.
Read the full study guide
The full guide is part of every NAVLE plan, with diagnosis and treatment tables, figures, a quick review and self-test questions. Start a free trial to try the question bank, or log in if you are already a member.