There is no cure for insulinoma. If the ferret lives long enough, eventually it will reach a point where clinical signs cannot be controlled and euthanasia will need to be selected to address quality of life issues.
Lymphoma is one of the most commonly diagnosed diseases in the domestic ferret. In one large study by Li et al, lymphoma was the third most common neoplasm seen in 574 ferrets after adrenal disease and insulinoma. Although a possible retroviral etiology has been proposed, no virus has yet been identified.