Mammary tumours in the guinea pig

Mammary tumours are found in both female and males guinea pigs (although the latter have only rudimentary glands). Tumours are identified by means of palpation of the mammary region. In most cases mammary tumours are benign (fibroadenomas), however adenocarcinomas, locally invasive and rarely metastasising, are also possible. Surgical removal of mammary tumours is always indicated, with wide margins and subsequent histological examination. Lung metastases of mammary tumours are rare but possible: it is, therefore, advisable to take an X-ray of the chest before excising the tumour.