Visiting Vet: Something’s wrong with Gamaliel

Could it be hemangiosarcoma?

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The gentle chirp of crickets alerts me to a weekend text message from my answering service — a pleasant improvement from the days when every emergency was announced by the loud, adrenaline-producing jangle of the telephone. The text says something is wrong with Gamaliel, the golden retriever. I had seen Gam a month ago for his annual physical exam. At 9 years old, he appeared in good health. Blood tests done as “geriatric screening” had all been normal. “He seemed fine until this morning,” his owners reported when I called. “Then he lay on the bed, breathing very fast and shallow, and he yelped when jumping down.” I wasn’t overly concerned about one yelp, but persistent abnormal respiration warranted immediate attention. “Come on down,” I advised, then went to prepare for radiographs. Nowadays, many veterinarians have digital X-ray equipment, but as a small solo practice, that has been beyond my budget. I still use actual film and a darkroom. While warming up my automatic processor, I thought about Gam. A 9-year-old golden retriever breathing hard? Even before seeing him, my first thought was a bleeding splenic tumor.

Hemangiosarcoma of the spleen is a highly malignant cancer arising from the vascular tissue lining. These tumors can rupture, leading to internal hemorrhage — inside the belly where owners can’t see it. Small bleeds may stop on their own, causing no symptoms other than transient lethargy and/or panting. Massive bleeds can lead to sudden collapse and death. Hemangiosarcomas account for more than 5 percent of all tumors seen in pet dogs, and most commonly occur at 8 to 11 years of age. Breeds predisposed include golden retriever, German shepherd, Portuguese water dog, Bernese mountain dog, flat-coated retriever, boxer, and Skye terrier.

When Gamaliel arrived, I immediately rolled back his lip to assess the color of his gums. People are often bemused when I suggest they check their dog’s color. “How do we do that?” they laugh, looking at their best friend’s furry face. Look at the mucous membranes inside the mouth. Although some dogs have brown- or black-pigmented gums, most will have areas devoid of pigmentation where they just look pink. Press a pink spot. It should blanch to white. Remove your finger. The pink should come rushing back within a few seconds. This is called capillary refill time, or CRT. Dogs who are bleeding internally will often be pale, with a slow CRT.

Gamaliel’s CRT was good, but his color was a bit paler than I would like. And he was a 9-year-old golden retriever. A study published in 2000 estimated that dogs of this breed have a one-in-five risk of developing hemangiosarcoma. I proceeded with my examination.

Temperature, normal. Heart rate, a little fast, but that was typical for him at my office. He was panting, but nothing out of the ordinary for a summer day. His belly was slightly tense, but I couldn’t palpate anything unusual. “Before taking radiographs, I want to check one thing,” I said. Abdominocentesis — the aspiration of fluid from the belly by needle and syringe. If Gamaliel was having a major bleed, I should find blood when I did this. I popped the needle through and aspirated. Nothing. I tried a second time. Nothing. OK. That was good news. Maybe.

When I was in school (before texting or digital X-rays) we were taught that 80 percent of splenic tumors were malignant, 20 percent benign. Benign tumors, however, can be just as lethal, as they also rupture and cause death by hemorrhage. Surgery was really the only option. There was no way to know definitively in advance whether a mass was benign or malignant. Surgery could cure a dog with a benign splenic tumor, but even with complete removal of the spleen, malignant tumors carried a grave prognosis. Microscopic spread happens early, and even with no visible evidence of metastasis at the time of surgery, most dogs with malignant tumors died within three months. There was a general consensus that larger tumors were actually more likely to be benign, but overall statistics were discouraging, and many owners opted for euthanasia rather than surgery. Now, more than 30 years since I graduated, we still do not have great options for presurgical diagnosis, nor are there really effective treatments for malignant splenic tumors. What has changed is that current studies suggest the odds are better than we used to think — closer to 50/50 for benign versus malignant.

Hemangiosarcoma can also occur in the heart, and splenic tumors often spread to the lungs, but Gamaliel’s abdominal and chest X-rays looked normal. “There’s a small area here behind his spleen that could be something,” I pointed out, “but it’s probably just a loop of bowel.” Maybe I had jumped too quickly to a diagnosis based on his breed and age. Maybe we were lucky, and his symptoms did not indicate cancer. Despite his recent blood work, we repeated those tests, and discovered a mild anemia and slightly low platelet count (cells involved in clotting.) These could occur with a splenic tumor, or with tick-borne disease, or with many other things. But my gut kept saying, “9-year-old Golden, 9-year-old Golden.” Next step would be an ultrasound, one more piece of equipment I didn’t have.

Gamaliel went to Cape Cod Veterinary Specialists, where an ultrasound revealed a small splenic tumor. After getting plasma transfusions to improve his clotting ability, his spleen was removed, but those 50/50 statistics still mean that half the time, these tumors are malignant. Tiny lesions that had not been visible by ultrasound were found on Gamaliel’s liver during surgery, suggesting probable metastasis. Post-operatively, he developed cardiac problems, but those seem to be stabilizing with medication. He is home now, but odds are he doesn’t have much time. It is a beautiful summer evening. As the stars start coming out, I hear the chirping of real crickets outside my window. I think tonight they sound a little sad.