Cancer is very common in pet hamsters. The incidence increases with age, as is the case with most animals, and is higher among females than males because of the variety of cancers that involve the female reproductive tract.
Tumours of hamsters may be benign or malignant and they are vulnerable to an unusually large number and variety of benign cancers.
Cancers involving hormone-producing organs, such as the thyroid and adrenal glands, are among the most common tumours found in hamsters. These cancers cause hormone imbalances, hair loss and changes in behaviour, as well as other significant signs.
If your hamster has a small external tumour, it is possible for your vet to perform surgery to completely remove it.
Internal tumors, however, are much more difficult to diagnose and remove. The small size of the patient, the even smaller size of the organs involved, the sometimes inaccessibility of the tumour, and the expense involved are some of the reasons why an owner of a pet hamster might elect for euthanasia (putting the pet to sleep) or maybe even do nothing, allowing the hamster to live out its life instead of performing surgery in these situations.