- Request Appointment
- Some Practical Matters
- Contact Us and Directions
- PRICE LIST
RAT MAMMARY TUMORS
Most masses on rats are benign mammary tumors called fibroadenomas.
Rat mammary glands extend along the underline from the neck to the pelvis, so mammary tumors can occur anywhere along the length of the body. They are common in male and female rats and can appear as early as a few months of age.
Less than 10% of rat mammary tumors are malignancies, the most common of which is adenocarcinoma. The only way to distinguish fibroadenomas from adenocarcinomas is with a biopsy.
Rat mammary tumors are almost always located outside of the abdomen or chest, but may become so large that they interfere with internal organs. In some cases, particularly when surgical removal is planned, imaging with x-rays and ultrasound is done to determine the extent of the tumor.
We recommend but do not require that the removed tumor(s) be sent to the pathology lab as a biopsy.
There is some evidence that spaying or neutering reduces the incidence of mammary tumors in rats when done as a preventive measure early in life, or after one or more tumors have been removed. It is this author's feeling that spaying or neutering is minimally helpful in preventing these tumors. We are always glad to discuss this option and provide the service if the rat's owner is interested. (Spaying or neutering can provide other benefits unrelated to the tumor)