The Silent Killer – An Update

Jett May 2016
Jett – May 2016 – enjoying the outdoors.
Tesla at Three-Dog Bakery
Tesla – February 2016 – two days before her passing.


Cancer sucks. Period.

It has no boundaries and does not discriminate on whom it touches. This article helps explain a silent killer many dog owners are not aware of that can come on suddenly and leave behind only heartache.

In February 2016, we lost our Entlebucher Mountain dog, Tesla suddenly after she had a splenectomy to remove her enlarged spleen (splenomegaly). The surgery was sudden. Her dying was even more sudden. In the span of three hours, she was gone from our lives. I stayed with her until the last of her warmth left her body. Our hearts are still breaking and gradually healing along the way.

Tesla was the companion dog I’d always dreamed of. Her only bad quirk was being scared of thunderstorms. Facebook is great for connecting people, especially long distances. The social media site connects you to people you’d never dream of…

A few years ago I connected with Tesla’s, aunt, Sue who has her brother, Jett. They live in Washington. Then a little while later I connected with Tesla’s other aunt, Jane who has her sister Jura. When Sue posted earlier this year that Jett was not feeling well she took him to the vet to get checked out. During the examination, they found his spleen had ruptured. I immediately decided to take Tesla in for a checkup as well – just to make sure nothing was wrong with her. Plus – at 10-years old having a full blood panel done was a must. Tesla had been very vocal the last couple of months of her life and we attributed it to her being “an Entle.” The day before the appointment she all of sudden stopped eating but remained vocal.

My heart sank when the x-ray revealed her spleen was enlarged but was still intact. It was immediately removed the next day. While I never saw the lab results from the spleen itself, I took the word from the vet that it was indeed hemangiosarcoma.

Talk about a gut punch. How could two dogs from the same litter wind up with the same cancer? Jura, their sister was tested and for precautionary measures had her healthy spleen removed. Immediately, I contacted the breeder we got Tesla from and informed her to notify the other dog owners of that litter. Sadly, she never acknowledged my email.

If you don’t know a spleen’s function it helps fight infection. It filters out and destroys old and damaged blood cells. Plus, it prevents infection by producing white blood cells called lymphocytes. It’s the first line of defense against invading pathogens. It also stores red blood cells and platelets.

When the spleen is enlarged it affects each of these vital functions. As the spleen grows larger, it begins to filter normal red blood cells and abnormal ones reducing the number of healthy cells in the bloodstream. It can also trap excessive platelets. Eventually, these excess red blood cells and platelets can clog the spleen, interfering with its normal functioning. An enlarged spleen may even outgrow its own blood supply, which can damage or destroy sections of the organ. In the case of Tesla’s spleen, it was engorged with blood. Thankfully, she did not need a blood transfusion from her sister, Azrael.

The following is from Jett’s mom, Sue, on this silent killer disease many don’t know about or understand, that not only effects Entlebuchers, but other dog breeds too.

Jett, my 10-year-old male Entle, had his rupturing spleen and tumor removed on February 1, 2016. The biopsy revealed that the tumor on his spleen was hemangiosarcoma. Not knowing what this was and what it meant, I researched this disease.

Hemangiosarcoma is a blood-borne (blood vessel cells) aggressive cancer, which usually starts in the spleen then metastasizes into the liver, lungs, brain and/or heart. It is found in all dog breeds and is appearing in our beloved Entlebucher breed. It was recognized in dogs in 1970. How long it has been in Entles is unknown. But, with better diagnosis and owners doing necropsies, we are discovering its presence.

Hemangiosarcoma is called the “silent killer” because there are no obvious symptoms. One day your dog is running around full of spunk and energy. The next day it is listless, hanging its head down, weak, constipated, not eating or has a fever. Death usually follows within a short period of time. The apparent suddenness of this disease is devastating to the owner. In addition, owners experience guilt because they feel that they should have seen the symptoms.

Symptoms vary from a sudden sharp yelp, abdominal distension and/or pain, weight loss, pale gums/mucous membranes, increase in heart and/or respiration rates, constipation, or fainting might occur. The disease usually occurs in older dogs – 8 to 10 years old.

I know of three Entles where hemangiosarcoma has been verified as the cause of death. One of the dogs died in 2004. She was eight years old and displayed no symptoms. On the day of her death, she jumped up to greet her owners and gave a loud yelp. Then seemed fine. When the owners went to leave to for work, she was lethargically laying on the couch. They checked her gums and they were white. Immediately, they took her to the vet’s and she underwent surgery. Her spleen and heart contained hemangiosarcoma tumors. Unfortunately, the dog died on the operating table.

Since 2014, five dogs have been diagnosed with hemangiosarcoma. Four are deceased. Each displayed different symptoms of this disease. The only reason why we know they died of hemangiosarcoma is that the owners had a biopsy/necropsy performed on the tumor(s). The dogs:

  • Dog 1, a nine-year-old male had a cough that was misdiagnosed as kennel cough. After coughing up blood, a chest x-ray was performed. The owner was informed that the lungs were full of tumors. After death, a necropsy was performed. It was found that the cancer had metastasized.
  • Dog 2, a lively healthy seven-year-old male had different symptoms. He was constipated and then could not urinate. A large mass was found behind his prostate inhibiting the passing of feces and urine. Ultra-sound revealed nodules in the lungs and one near his spleen.
  • Dog 3, again a healthy apparent lively seven-year-old-male suddenly froze in apparent abdominal pain, then displayed symptoms of a tight abdomen, rapid respiration, increased heart rate and didn’t want to move. His owner took him to the ER. Blood work and an x-ray revealed anemia and a splenic mass. The spleen was removed, as well as some spots on his liver. This dog survived the surgery and lived an additional two months. After severely cutting himself, which would require surgery, his continued anemia, and his terminal prognosis, his owner decided to euthanize him.
  • Dog 4, a healthy appearing 10-year-old female awoke one morning with a temperature and not wanting to eat. Because her littermate brother had recently had his cancerous spleen removed, her owner took her to the vet to be checked out. An x-ray revealed something was up with the spleen. She was kept overnight to stabilize her temperature. Then operated on. Her removed spleen was full of cancerous tumors. Sadly, this dog died 10 days later.
  • Dog 5, Jett. Last November, Jett, an apparently healthy 10-year-old Entle, started having “spells.” He would hang his head down, breathe with his mouth open, and was lethargic. This lasted several hours; he would then seem to snap out of it. We put it down to something he ate as Jett eats everything and loves fruits/ vegetables. Wrong! At the end of January, we were in the local dog store during another one of his “spells.” The owner of the store checked him out and strongly urged us to get him to the vet ASAP because his gums were almost white. Turns out he was having a “bleed” and had a small tumor on his spleen. The vet couldn’t operate on him until the following Monday. Over the weekend I watched his distended stomach grow knowing he was bleeding again. Jett’s hemangiosarcomic spleen was removed February 1st. At the two-month mark, Jett was doing well. I have him on two supplements to help fight any additional cancers in his body.

Primary Tumor Sites

  • Approximately 50% of hemangiosarcoma tumors originate in the spleen.
  • 35% of tumors originate in the heart, liver, kidneys, muscle or bone.
  • 15% of tumors develop on or under the skin.

Post-diagnosis options can include chemotherapy. In addition, some people try using products to help the dog’s immune system or ones that contain properties that help fight cancer. But these products probably do not have scientific data proving their effectiveness.

Many questions remain:

  • Is there a genetic component? (studies in Golden Retrievers suggest this is so)
  • Is the tendency to produce cancerous blood cells carried on a recessive gene?
  • Is it multi-generational (meaning does it skip generations)?
  • Is diet a factor?
  • Is environment a factor (in the case of Tesla living in the Texas Panhandle and Jett living on the coast of Washington both are completely different region types so this may not be a solid factor for consideration. Yes – there is still a possibility something similar exists in both places that affected the dogs.)
  • Why did Jett and Dog 3 survive? Was it because the cancerous blood cells had not settled in other tissues yet?

What can you do?

  • Be aware of this disease.
  • Familiarize yourself with the symptoms, especially the high temperature and not eating.
  • Work with and report instances to National Entlebucher Mountain Dog Association (NEMDA) Health and Genetics Committee and to other pure-breed organizations.
  • Notify the breeder immediately.
  • Encourage NEMDA and other pure-bred dog organizations to participate in the research studies of hemangiosarcoma.
  • Support others who have lost their dog to hemangiosarcoma


American College of Veterinary surgeons:

American Kennel Club’s Health Foundation:

National Canine Cancer Foundation: 


Update on Jett June 2016: The vet was pleased with his overall health and recovery. Jett’s lymph nodes felt normal and not swollen. Jett’s heart sounded good and his lungs were clear. Jett also had put on 1/2 lb. Hopefully, Jett can make his checkup appointment on October 1st, but it is in God’s hands.

July 2016 Update: It is with heartbreaking news to write that Jett passed away on July 14, 2016. He lived almost six months after Tesla passed.

In parting both Jett and Tesla will live forever in our hearts. They were our companions for 10 years. They brought Sue and I together in friendship. Sadly our losses only remind us that in the end  – cancer sucks until there is a cure for all cancers.


Story by ©Sue Thom and Christena Stephens

Photographs by ©Sue Thom and Robert Cason