Gastric, Liver and Prostactic carcinomas, adenomas and Adenocarcinoma
in dogs
Hepatomas,
hepatic adenomas and hepatocellular carcinomas
Gastric adenocarcinoma
Prostatic adenocarcinoma
also see Cancer
also see Carcinomas
also see Perianal
Adenoma
also see liver cancer
also see dog lumps
Please note: The most recent medical information is at
the top of the page to least current at the bottom.
Hepatomas,
hepatic adenomas and hepatocellular carcinomas
Question: Dear Dr. Mike:
Just got back from seeing the oncologist as recommended by my vet.
He also thinks I should have the liver biopsy but gave me his opinion
about
what he thought 99s liver mass could be. Unfortunately I can't
find anything
on your site about it or anywhere on the web. The oncologist
states she has
a rare condition either way and it is a unique case. He thinks
she's got a
primary liver tumor or sarcoma with insulin like pentacles secretions.
After
redoing her x-rays which confirmed there is nothing in the lungs, he
said
it's likely a hepatoma.
Is a hepatoma the same as hepatocellular adenoma and is primary liver
tumor
or sarcoma with insulin like pepticles secretions the same as hepatocellular
carcinoma?
Would you be kind enough to let me know what you know about these conditions
and where I might search for additional cases or articles concerning
same.
The only thing I can find information or related articles is osteosarcoma.
That's involving the bones right. I can't find anything on canine
liver
sarcoma.
Thank you again for your valuable assistance. I really appreciate
it. Sara
Answer: Sara-
If there is no evidence of a metastasis it is sometimes possible to
remove
hepatomas surgically. They often only involve one lobe of the liver
and the
remaining liver tissue is more than adequate for life after the removal
of
one lobe, if that is the case. Hepatomas have been reported to cause
hypoglycemia due to the release of hormones (insulin like growth factors)
which bind to the same receptors on the cell as insulin and thus block
its
function.
It is hard for me to tell you for sure what the relationship between
hepatomas, hepatic adenomas and hepatocellular carcinomas is. It seems
hard
for pathologists to differentiate between hepatomas and low grade
hepatocellular carcinoma based on a couple of pathology reports we
have
seen in which the pathologist listed both conditions as possibilities.
In
either case there is a chance that surgery could be curative because
the
hepatocellular carcinomas are supposed to be pretty slow to metastasize.
I
know that it is a really big decision to consider surgery, especially
since
it is probably best to seek out a surgical specialist, but this is
a
situation in which there is a possibility for a good outcome even with
a
large tumor (the largest I have heard of that involved one lobe and
hadn't
spread based on the dog's subsequent lifespan was 8 inches in diameter).
We
had a patient with one of these that was very close to that size. I
think
that a sarcoma would likely be a hemangiosarcoma or leiomyosarcoma,
which
would not have a good prognosis.
If you go to the PubMed web site http://www.ncbi.nlm.nih.gov
and use the
search term "dog hepatoma/ve" (the /ve is a "switch" to
make it possible
to sort out the articles of veterinary relevance), you can find a number
of
abstracts relating to liver tumors in dogs. There was a Clinics of
North
America issue in 1995 on liver disorders which had some information
on
liver tumors and the book "Textbook of Veterinary Internal Medicine,
5th
Ed." has some information on these tumors.
It is really scary to contemplate removal of a large portion of the
liver
but there are enough success stories with this procedure to make it
worth
considering, if you would like to pursue all options.
Mike Richards, DVM
2/19/2001
Gastric adenocarcinoma
Question: I'll try to be brief but there is alot to explain.
Our dog, Smokey, a
collie/black lab mix, is 11 years old. Began vomiting everyday (in
the morning
upon waking and getting up) food from the previous day's meal, undigested.
He's lost close to 20 lbs, going from 110 lbs. to 89 lbs. Our vet took
blood
and everything was normal; i.e., kidneys, liver, etc. Began feeding
him small
meals 4 times a day of a gruel, boiled hamburger and rice put throught
the
blender to be smooth consistency. He was able to hold down this. Vet
suggested
x-rays and possible GI series. He did an x-ray and stopped. Found a
large mass
(approximately softball size) in him. We were told either do an exploratory
or
assume the worse and let him go. We couldn't live with ourselves until
we knew
we'd done all we could. We got the opinion of another vet who
suggested an
ultrasound. This was done and confirmed the mass in the pyloric region.
We
talked to a surgeon who thought an exploratory would work because other
than
the vomiting, he was healthly. She also did a chest x-ray and found
no obvious
tumors in his lungs. His blood work was good and he is a strong dog
both
physically and in spirit. They did the surgury on July 18th.
The mass (per the pathology report) is adenocarcarcinoma, well differentiated,
stomach. The surgeon said she had to remove the pyloric region but
left the
bile duct in tact. She said she got good margins. The biopsy says:
Sections of a gastric mass are examined on 8 slides. There is a partially
delineated, discrete modular mass in the submucosa. It is composed
of
neoplastic epithelial cells that form acini and dilated ducts within
a
fibromuscular stroma. The cells have ovoid mulei with marginated chromatin,
finely stippled chromatin. Nucleoli are small, but visible. The mitotic
rate
is low. The cytoplasm is abundant, polyhedral with distinct cell margins.
The
surgical margins examined are clear. The neoplasm in the gastric plylorus
has
apparently developed from submucosal glands (brunner's glands). The
neoplasm
is histologically well differentiated. This suggests a low grade of
malignancy
and a limited metastatic potential. Surgical excision appears to be
complete
but the prognosis is still guarded.
Small masses were found on the liver but are determined by the pathologist
to
be hepatic nodular hyperplasia; the vet said normal for an older dog
and not
of concern.
The surgeon consulted with an oncologist who says chemo and/or radiation
would
probably not be necessary nor is there any proof it would help. However,
the
surgeon and oncologist think there is a 50/50 chance the dog is cured.
Our vet
is not as optomistic. He said the likelihood is that the cancer will
creep up
elsewhere in the future. He said even though it is a slow growing cancer,
that
the size of the tumor indicates he's had it for a while. He also said
even
though the surgeon didn't find any other tumors on his liver, kidneys,
stomach, etc. that we should not expect the dog to be completely cured.
He
tells us we might have a few months to a year with the dog. The surgeon
says a
year to two, maybe more. She took his staples out yesterday, said the
area
looks good; he hasn't vomited since the day of the surgury, had one
small bout
of diareaha and appears to be getting stronger by the day. She told
us to only
feed him canned food, no dry food, no table scraps, no bones. She explained
that the pyloric valve she took out prevents any large pieces of food
from
entering the small intestine and that we should be careful with what
he eats.
I'm sorry this is so long. Basically just want your opinion. Our vet
is very
pesimistic and the surgeon is very optimistic. We are confused. Give
me your
OPINION on how long Smokey is likely to live. If the cancer is still
in him
but in another area, what type of symtoms should we watch for. We are
walking
on egg shells now. Afraid to let him do the things he loves; hiking,
swimming,
running for fear he'll over do and get worse. The surgeon said he could
swim
in another week and do as much as he wants to do. What do you
think?
Thanks for letting me write so much and for just being there for us
devoted
pet people who need advise.
Sincerely, Linda
Answer: Linda-
Gastric adenocarcinoma is best treated surgically. I can not find any
research showing a benefit for chemotherapy and radiation therapy is
not
recommended due to complications in using radiation therapy for
gastrointestinal problems. When the entire tumor is removed and there
is no
evidence of metastasis to surrounding lymph nodes or organs at the
time of
surgery the prognosis is still guarded, meaning that recurrence of
the
tumor is likely even in this case. The average life expectancy post
surgery
for this type of tumor is probably only six months to a year, but patients
do seem to be comfortable most of that time, at least in the very small
number of cases in which we have diagnosed this problem and attempted
surgery. I found a couple of anecdotal reports in which remission periods
of longer than a year were reported, though.
Surgeons tend to be optimistic by nature. It takes a certain amount
of
optimism just to do surgery, considering the risks of anesthesia and
routine surgical procedures and then to want to take on the added risks
of
removing portions of vital organs just takes an attitude in which a
person
believes things will turn out OK. Vets who practice primarily
medicine
tend to be a little more pessimistic, especially about surgical outcomes.
Oncologists tend to be somewhere between these extremes, so the fact
that
the oncologist feels that there is a 50 percent chance of a cure is
pretty
good.
Most older dogs recover pretty well from surgery, so the surgery itself
doesn't impair their enjoyment of the remaining time they have, whether
it
is a short time or a long time. So I think that most owners don't regret
attempting surgery, as long as the anesthesia and operation go OK,
even if
it doesn't turn out that it gives a long term cure.
The pathologist's report is very encouraging. I think it is reasonable
to
hope for a cure from the surgery, based on that. If lymph nodes from
the
region were removed and also found to be free of cancer, that would
even be
better. The lack of metastasis on the liver biopsies is also very good.
I
think it is reasonable to hope for a cure but it would be best to temper
that hope with the realization that many of these tumors have spread
by the
time they can be diagnosed and removed. I would let him do all the
things
he likes to do, when your surgeon feels it is safe (usually two to
three
weeks after surgery). You should reintroduce him to heavy exercise
slowly,
though. Let him build up strength over a couple of weeks before allowing
him the opportunity for uncontrolled exercise.
Good luck with this. I do all the surgery in our practice, so I have
optimistic leanings --- so I'll hope that Smokey does really well.
Mike Richards, DVM
8/7/2000
Prostatic adenocarcinoma
Q: I have a four year old (neutered, yes neutered,
when he was 14 months) Samoyed who has just been diagnosed with prostatic
adenocarcinoma. My vet is currently--as I type--calling oncologists for
help on treatments. I am told that this cancer is generally very resistant
to treatment, that it moves very quickly and that most dogs are dead within
three months of diagnosis. He is having difficulty urinating and defecating,
so we do not have the luxury of time. Typical treatment is radiation and
surgery. A complication is that his kidneys are not in good shape. The
vet who did the ultrasound said that they look like the kidneys of a 10-11
year old dog. This dog has a history of an elevated BUN (usually 29-33),
something we first noticed when he was nine months old, and have retested
every six months or so. Last November, his BUN was at an all time low of
27. Last month when he was in for his annual checkup, it was 17. Today,
it is 12. Urine looks fine, except that it is quite dilute. Creatinine
is fine and always has been. Other than the BUN, he has been quite healthy,
is in good physical condition. Unfortunately, his breeders lost interest
in him as soon as the check cleared the bank and I do not know much about
the longevity of the dogs behind him. His breeders are known (I know now)
for producing very cutsey puppies who do all kinds of winning from the
puppy classes and then aren't seen again. He matured very quickly, especially
when compared to my younger dog, from different lines. I am just trying
to get as much information about this type of cancer, possible treatments
(allopathic and otherwise), etc. I'm wondering if there might be environmental
factors in the onset of this? Genetic? Why does my young, neutered dog
have it? Any info is greatly appreciated. Ann
A: Ann- Four years of age is pretty young for prostatic
adenocarcinoma. It would also be young for the most common confusing differential,
transitional cell carcinoma of the urethra. This can be confused with prostatic
adenocarcinoma pretty easily if the biopsy to determine the cancer status
was done by a fine needle aspirate. It is also possible to confuse rectal/colon
tumors with prostatic tumors using fine needle aspirate biopsy techniques.
Young large breed dogs are reported to be prone to rhabdomyosarcomas in
"Small Animal Surgery" by Fossum. These are actually a bladder tumor most
of the time but again, it is in the region of the prostate and perhaps
could be present.
Neutering does not seem to protect dogs against prostatic adenocarcinomas.
It does protect against problems with benign hypertrophy leading to problems
urinating, etc.
Consulting with an oncologist (or more) is a good idea. The current
thinking is that radiation therapy and perhaps concurrent chemotherapy
offer the best hope for increasing survival times but surgery has some
proponents and I vaguely recall hearing about a new surgical procedure
--- but I can't even begin to think of where to look for that information.
The oncologist is likely to be up on the latest information, though.
The current BUN values are normal. In a dog with a history of elevated
BUN values it might be a good idea to check liver function before doing
anything too invasive. When the liver fails the BUN drops because it produces
the precursors to BUN. When the BUN value is less than 10 this has to be
considered if there are any clinical indications to do so. It seems to
me his history alone is sufficient reason.
I can not answer the questions regarding potential habitability, nor
potential environmental influences. There is no mention of a genetic predisposition
that I can find and no known environmental influences that I am aware of
but that doesn't mean much.
Mike Richards, DVM