How do mammary tumors present?
Owners may feel one or more firm nodules near a nipple. Masses can be small and mobile or larger, fixed, ulcerated, inflamed, or painful. Multiple mammary glands can be involved.
Dogs and cats are different
In cats, a high proportion of mammary tumors are malignant and often biologically aggressive. In dogs, both benign and malignant mammary tumors occur. These species differences affect counseling and urgency.
How are they staged?
Evaluation can include measurement of tumor size, lymph-node assessment, chest imaging, bloodwork, and additional imaging depending on the case. Definitive tumor classification usually requires histopathology after biopsy or surgery.
What does treatment involve?
Surgery is the main local treatment for many operable mammary tumors. The extent of surgery varies by species, number and location of masses, and surgeon assessment. Oncology consultation may be recommended for malignant or advanced disease.
What about spaying?
Hormonal exposure influences mammary-tumor risk, especially when spay timing occurs early in life. For an animal that already has a tumor, whether to spay at the time of surgery is an individualized decision based on age, reproductive status, tumor biology, and overall health.