Both Male and Female Guinea Pigs can Develop Mammary Tumors
You may notice a lump in the chest area and there may be bleeding of the teat. Surgical removal of the tumor is recommended to avoid rupture or abscess. Evaluate the guinea pig as a surgical candidate. Although most mammary tumors are not cancerous, you may wish to send the tumor out for a histopathology for more information.
Briana D's guinea pig, Quincy, developed a mammary tumor similar to another guinea pig of hers (Sal). Her preliminary histopathology identified the tumor as a Mammary Tubular Adenocarcinoma. A later report stated that Quincy's margins came back clean.
Find below a picture of Briana D's guinea pig, Quincy:
And her guinea pig Sal:
Quincy, post surgery:
Sal, post surgery:
Sal, incision healed:
In October of 2010, Murmeli posted in the medical forum about her guinea pig Sissi, who had a mammary tumor removed in December of 2007. Sissi was also spayed in May of 2009 and recovered well from both surgeries.
Photos of Sissi's mammary tumor:
Post op pictures:
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