There are two types of tumor : benign  and malignant. It is said benign when the tumor does not have ability to attack other tissues- Metastatic tumor- but  malignant  has this potential to make metastatic tumor to involve other organs.On the basis of pathological study there are some characters for malignant and benign tumor which are not necessary to mention them here.Any bump on the mammary gland can be a tumor but not all of them.Female dogs and cats are prone to affect by this tumor but those who are intact have high risk for mammary gland tumors because progesterone is a risk factor for this neoplasm ( tumor)

Obviously enough ovariohysterectomy ( Spay) in early stage of life can decrease the chance of this tumor in pets.Another factor is genetic , in some breeds like poodle and German shepherd or Persian cats.This tumor can affect one or more than one mammary gland.It can have very fast growth or slow growth, can be capsulated or diffuse, edematous or non-edematous. Therefor if your pet has a bump on the breast needs investigation by your vet.

Diagnosis is based on examination and biopsy.Any  mass in this area needs biopsy to diagnose it’s behavior : malignant or benign.

Treatment includes surgery, radiotherapy and chemotherapy.On the basis of your vet decision one or all of them can be used.

Prevention is based on the spay surgery before the first  heat (bleeding).It has been approved that there is a correlation between the time of this surgery and the rate of mammary gland tumor.It means ovaryhysterectomy before the  first bleeding has the lowest chance and after that the chance is higher.