Hyperthyroidism in a Cat (Thyroid Neoplasia)

This case involves a 12 year old cat that had been suffering for months with an increased appetite and loosing weight.  Blood work was completed 2 months ago and revealed a mild to moderate increase in the liver enzymes.  The animal was started on medicine for the liver and was told to check back in 1 month.  The animal continued to decline, and by January of this year, the animal was getting weaker and still loosing weight.  A T4 test was done and the result was consistent with chronic hyperthyroidism.  After a diagnosis of hyperthyroid was made, different treatment options were discussed with the owner and surgical treatment was chosen.  Surgical intervention has the best chance of curing this animal, where medical management will only treat the symptom.  No palpable mass was detected in this cat, so an MRI was performed to check for thyroid neoplasia.  The scan below shows the tumor clearly.  This cat had severe thyroid neoplasia involving the right thyroid lobe.  Surgery was done and the animal recovered uneventful.