Mitten – May/June 2012

When Mitten initially came to see us we ended up taking some blood tests and diagnosed an overactive thyroid gland. Hyperthyroidism in cats is usually caused by a benign growth on one or other of the thyroid glands in the throat, The tumour produces excess thyroid hormone which increases the metabolic rate. The heart has to go much faster in order to supply the body with enough oxygen to meet the demand and the cat usually loses weight as a consequence of burning energy faster than they can eat it! Eventually they can die from heart failure as, like any muscle, the heart enlarges when it is going too fast and then can’t work properly as a pump.

We can treat hyperthyroidism with medication (a drug called felimazole), surgery or radiation therapy. Mitten was started on tablets but very soon came back to see us quite poorly. At first we thought it was something to do with her tablets but then discovered that she had severe pain at the front of her tummy and thought we could feel a lump. When we ultrasound scanned her tummy we found she had a tumour invading, but confined to one of her liver lobes.

We sent Mitten home with painkillers whilst her owners considered various options for further investigation and treatment. In the end they bravely elected to have surgical exploration.

A few days later Mitten came in for an exploratory laparotomy. The photograph below shows the extent of the tumour invading her liver. At the edges near the surgeon’s left thumb and right forefinger you can  just see a small area of more normal liver.

We operated on the liver and removed the whole lobe of the liver where the tumour was growing. Mitten came round uneventfully and was soon home with her owners. Fortunately cats only need a relatively small percentage of normal liver to survive so the fact that we removed a liver lobe didn’t affect her, especially given that the rest of her liver looked normal and healthy.

Mitten is pretty much back to leading a normal life now and her hyperthyroidism is starting to stabilise with medical treatment.

We sent the tumour from the liver away to a pathologist who said that it was benign, we have removed all of it and it should never come back or bother Mitten again.

She will still need monitoring at intervals to make sure we are treating the thyroid problem effectively, but she should leave a normal life for a very long time to come.

It is so lovely for the Vet, the Patient and the Owners when we manage to cure a patient. That is one of the reasons why we wanted to share this story with you. Mitten is probably oblivious to all that has gone on, and in many ways that is good. But at least we all understand it now and can be grateful that we had the skill and knowledge to cure and treat her.