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view previous Case of the Month studies:
 Brutus,
is a sweet, but sometimes feisty 11 year old Chihuahua who presented to
us for a routine dental cleaning last month. Brutus has had problems
with periodontal disease and has had to have many teeth extracted over
the years. As a result, the owner brings him in yearly for dental
cleanings.
We've been treating Brutus for years, and when he came in, he just
didn't look good. He had lost weight, his coat looked dull and scruffy
and he was breathing rapidly. On physical exam, we found advanced
periodontal disease in the mouth. His lungs sounded harsh and as a
result, we suggested blood tests and chest radiographs prior to
proceeding with the dental work. We always do blood tests prior
to surgery and generally recommend chest films for all dogs over 7 years
of age.
His blood tests were normal for a dog of his age. The chest
radiographs, however gave us a big surprise. As you look at these
films, you can see that the left side of the chest is all white while
the right side is black (full of air).
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| Notice the white patch in the
upper left corner of the chest. This is the mass |
You can see the white patch overlying the
heart, which is the tumor |
Based on these findings we were highly suspicious of this being a
tumor, however an abscess or granuloma was also possible. We
examined the lesion with ultrasound and found it to be a solid mass
measuring 2.5 x 4.5 inches. With ultrasound guidance, we
were able to get a sample of the mass for analysis. The cytology
slides were sent to the lab and 3 days later we got a finding of a
primary lung tumor. Lung tumors are a relatively uncommon
tumor in dogs. They can vary in their aggressiveness and the
overall prognosis for treatment can only be determined after a full
biopsy is examined and the local lymph nodes (around the heart) are
inspected. Surgical excision of the mass is the treatment of
choice for this type of tumor as response to chemotherapy and radiation
therapy is very limited.
We took Brutus to surgery and opened his chest (thoracotomy) to find
the entire front portion of the left lung involved in the tumor.
This part of the lung was no longer performing the function of gas
exchange, so there was no problem removing it from the standpoint of
Brutus' ability to breath. We removed the lung lobe and sent it to
the lab. After thoracotomy, we have to leave a chest tube in the
thorax for 24 hours in case there is any leakage of air from the
surgical site. Brutus was taken to the overnight emergency clinic
for observation. He had an uneventful recovery and we removed the
chest tube the next morning.
A few days later, we received the biopsy report indicating that this
was a tumor arising from the bronchial and alveolar (gas exchange area
of the lung) tissue. The borders of the biopsy did not show any
sign of tumor cells. Because there is no strong evidence that
chemotherapy would prolong Brutus' life, the owner opted not to pursue
it. Statistically, dogs with this type of tumor which
has been fully resected have an average survival time of 12 months,
however some live as long as 3 years.
Brutus is back at home and is as feisty as ever. He is
completely comfortable and he and his owner are enjoying their time
together.
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