Case Report: Myxoid Liposarcoma (Cancer of the Fatty Connective Tissue)

Arnold, a seven-year old Rottweiler, was taken to his regular veterinarian after his parents noticed a protrusion in his abdomen when he was lying down.

Arnold’s regular veterinarian took chest and abdominal x-rays and found a large abdominal mass. They referred him to the Emergency Division of the Veterinary Referral Center for an ultrasound to determine how the mass was attached in the abdomen.

Two years prior to this episode Arnold had experienced chronic gastrointestinal issues. An ultrasound was done then and Arnold was diagnosed with thickening of the small bowel. He was put on Prednisone and a homemade diet. His symptoms had been well controlled.

Two weeks before finding the abdominal mass Arnold’s parents noticed that he was drinking more water. However, they did not note a change in urination. Arnold was still eating well with no vomiting or diarrhea.

The ultrasound examination showed that the mass was attached to the spleen. Splenic masses are relatively common in larger breed dogs. Arnold was transferred to the Surgical Division for an abdominal exploratory procedure.

Dr. Bradley performed the exploratory procedure and discovered that the abdominal mass, which was volleyball sized, was attached to the spleen by adhesions only. It did not originate from the spleen and Arnold’s spleen appeared normal. However, his spleen was removed due to the number of adhesions involved. Dogs, like people, can live without a spleen. The mass appeared to be originating from the serosa (tissue covering) of the colon. Dr. Bradley was able to successfully remove the mass without damaging the colon. Upon examination the liver appeared to be within normal limits.

The mass was sent to a laboratory to determine the pathology. Unfortunately, the laboratory determined that the mass was a cancerous tumor called a myxoid liposarcoma (cancer of the fatty connective tissue). Research suggests that this type of cancer is relatively rare is dogs and does not seem to be prone to metastases.

Arnold is grateful that his parents noticed that his abdomen didn’t look right and took quick action to find out what was going on. Arnold’s Mom reports that he is back to being the happy boy that he’s always been. We are so pleased!