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Bone Cancer - Osteosarcoma
Hemimandibulectomy - ear problems and weight loss after surgery
Bone cancer (osteosarcoma) or bone infection (osteomyelitis)
Bone cancer -Dilantin and phantom pain
Osteosarcoma
also see Diaphragm Problems
also see Tumor and Cancer
Hemimandibulectomy - Ear problems and weight loss following surgeryQuestion: Dear Dr. Richards:
I wrote to you in September 1999 after our ten year old Rottweiller
was diagnosed with a bone tumor in his lower right jaw. He
underwent a hemi-mandiblectomy, and he is doing fine.The surgery took about three hours, twice as long as the surgeon had
estimated. This was most attributable to Nikoli's being a Rottie and to
Rottie bone structure. (Underneath this loveable pooch is one tough puppy!
I certainly never gave the strength of his jaws, muscle and bone, much
thought.) Nikoli spent three nights in the surgical hospital; we took him
home on Day Four which happened to be a Friday. My husband and I both got
the day off from work, so we were able to spend three full days and nights
with him before he had to be left alone during the day. The surgeon gave
us three prescriptions: Rimadyl (100 mg); Cephalexin (500 mg) and
Torbugesic drops.The first couple of days at home, Nikoli just wanted to sleep and relax.
The right side of his face was bristling with stitches and a couple of
drains. He was still bleeding and draining a lot, and I was concerned
that he would tear his stitches or worse, so the first day or two I
literally hand fed him soft, canned food. But as Nikoli began feeling
better and his appetite increased, he started eating for himself. A week
(or maybe two weeks) later he went back to the surgeon for a follow up and
got gold stars for his progress (best of all, he didn’t need any
restitching). Within a few more weeks he was pretty much back to his old self.The muscles on the right side of Nikoli's face have atrophied. The bones
on the right side of his face have become very pronounced, especially the
bone over his right eye. The bones on the left side of his face have
become somewhat more pronounced as well, but they aren’t as noticeable
visually.
His mouth on the right side looks normal, but of course the lips were sewn
together up to a point to help hold his tongue in place and to help him
eat. But unless you are petting him on his face you don’t really notice it.
Still there is nothing like a dog’s very own jaw to keep a dog’s tongue up
in his mouth yes, Nikoli’s drops out when he is relaxed. We try not to
laugh in front of him.Nikoli takes much longer drinks than he did before, but I believe this is
because he is unable to lap up as much water in a single gulp as he used
to. He backwashes significantly more since his surgery, so we are
changing his water every day or every other day, because it gets “dog
mouth gunk” in it and begins to smell. And he also has a serious
post-drinking dribble problem. Outdoors this is no big deal. But inside,
I have begun keeping the mop next to his water station in the
kitchen. It’s that bad.He has dropped some weight. Before the surgery Nikoli’s normal adult
weight was 85 pounds. At the vet’s yesterday he was down to 75
pounds. Our vet would like to see him gain back that ten pounds . After
he recovered from surgery we switched Nikoli from a diet of soft, canned
food back to his usual dry kibble with occasional table scraps (we don’t
do a lot of home cooking, so scraps really are occasional). Now we are
thinking of incorporating a least a can of soft food a day. (I have a
question about this, but I will try to lump my questions together at the
end of this letter, so they don’t get lost in my ramblings.)The only other problem that Nikoli has now is a chronic (I think that’s
the word) ear infection. It gets better; it gets worse, but it doesn’t
seem to go away.This past week, I tried home remedies including hydrogen peroxide and
Monostat 7. Neither seemed to help, so it was back to the vet’s. The vet
examined his ears and took another culture. She confirmed that the
deeper, lower parts of his ear canals were very dirty. The culture
revealed no yeast (so the Monostat apparently did its job - maybe), but
there were several different types of bacteria thriving. After flushing
Nikoli’s ears, she sent us home with a couple of prescriptions and advised
that we stop home flushing his ears for now as this seems to be keeping
them wet while not really affecting the bacteria. Nikoli is now taking
Clavamox (250 mg tablets, 2/am, 2/pm) and Tresaderm drops in both ears (am/pm).He seems better today, but that may be due mostly to the thorough ear
flushing he got at the vet’s. It’s probably too early to tell if the
other stuff is working. He has a follow-up visit in two weeks. If this
treatment plan doesn’t seem to work, the vet suggests we try a different
type of culture that will allow her to isolate the kinds of bacteria that
are in his ears and allow us to treat for resistant bacteria if we need to.The right ear structure is more closed than it was before the
surgery. The loss of bone and muscle has apparently changed the way the
ear is supported. This makes things a little more challenging, but Nikoli
had this problem before his surgery. So this is not something that has
come up unexpectedly as a result of his operation.Well, maybe I should summarize:
Ears
Previous Treatment: Chlorhexi Derm Flush with Otomax Otic (can’t they
design a container that will make it easier to judge how much Otomax
you’re squeezing out of the tube and into the ear?)Current Treatment: Clavamox and Tresaderm
Questions:
Would Witch Hazel make an effective ear flush?
I dropped by www.vetinfo.com/dogear and read up on ear problems. After
reading your comments on home remedies, I realize that I should have been
diluting the hydrogen peroxide (ooops). I didn’t think about vinegar, but
I was wondering if witch hazel (which has an astringent quality) would be
effective. By the way, when I tried the Monostat I did realize that it
would only affect yeast (if it was present), not bacteria. I cannot say
for sure that there was yeast in Nikoli’s ears before the Monostat, but
the vet said she didn’t find any when she tested for it. However, given
that the Monostat didn’t and can't solve Nikoli's ear problem, I don’t see
any reason to use it again.What is the best way to feed Nikoli and get him back, closer to or at his
old weight?We currently feed him Kibble-N-Bits. We switched a few years ago after
reading a pet food comparison study done in Consumer Reports. Up until
then we had always fed him a “premium” dog food. As a puppy he started on
Science Diet, later we tried Iams and others (Nikoli’s “dad” usually
bought the food, and I think he got whatever sounded good to him even
though he wouldn’t be eating it. My husband would adamantly deny this, of
course.)
In the Consumer Reports study, Kibble-N-Bits stacked up well against the
premium stuff: same nutrition, but lower fat, lower price and increased
availability. So we switched.But now he seems to be losing weight. The vet suggested adding canned
food to his diet. We have two theories on canned food. 1) mix it with
the dry and he will eat more over all; 2) feed him the canned separately
and let him “top off” with the dry. The down-side to Theory 1 seems to be
that Nikoli might still eat less; instead of finishing his dish, he might
leave behind both the canned and the dry. The down-side to Theory 2 seems
to be that he will finish the can, but won’t top off with the dry, so he
is still eating less. We haven’t tested either of the theories on Nikoli
(but I have seen dogs in the past practically lick the canned food off the
dry kibble, leaving it right there in the bowl otherwise untouched.)While he was on a soft food diet, he was eating about three large cans a
day. Now I am thinking one can a day along with the dry food would be a
good supplement. Is one can a day enough?Should we look for a dry food with more fat in it? (Nikoli has always
been a very fit dog, never, ever fat, in part, because we never neutered
him I could not get my husband on board with that one. I must add that
to our knowledge our dog is still a virgin even at the ripe age of 10
years. I could not and would not stand to be responsible for even one
more litter of pups, planned or unplanned, in this over-populated world,
so we have been very careful to keep Nikoli away from temptation. --still
a virgin and always a very docile and gentle dog, contrary to the usual
unneutered male expectations.)What can we expect related to Nikoli’s upper right jaw now that it no
longer has its lower chewing surface? Tooth decay comes to mind, since
these teeth will get none of the cleaning benefit of dry, crunchy
food. Should we start brushing his teeth? What are your recommendations
regarding toothpaste, etc.? Will his upper teeth grow longer with not
lowers to grind them away (that sounds more like a rat problem than a dog
problem)?Are you aware of anyone doing post-mandiblectomy studies on dogs? I would
be interested in finding out more about how dogs get along after the surgery.Well, thanks for your patience. This note has turned into a bit of an ear
bender. Thanks for listening. We're looking forward to your comments and
thoughts.Lisa
Answer: Lisa-
I am pretty sure I'm going to miss some of your questions, so please feel
free to resend any that don't get answered.
The simplest way to add calories to a dog's diet is to add a tablespoon or
two of oil to the food. This adds a lot of calories without changing the
dietary balance of vitamins and minerals much. This works with either
canned or dry food. If additional calories beyond this are necessary you
can get them by feeding either canned or dry food in whatever quantity it
takes to support a weight gain. Then you need to cut back when Nikoli gets
close to his optimal weight so that his weight levels off rather than
continuing to increase. Ordinarily there is no particular advantage that I
can see to premium dog foods but they are helpful in situations like yours
in which a dog needs to gain additional weight and where it may be helpful
to feed lower volumes of a premium food rather than adding additional cups
or cans of a non-premium food. I would consider this if you think that
Nikoli won't eat larger amounts of food or can't eat more food comfortably.Teeth problems associated with hemimandibulectomies tend to be problems
with the bite on the opposite side being affected by the surgery because
the mandible becomes less stable on that side. Most of the time this isn't
a severe problem but sometimes there is enough impingement on the gums or
palate to cause problems based on literature references. We have had two or
three patients who have had this procedure and I don't recall any major
problems with tartar on the upper teeth on the side that the jaw was
removed nor do I recall serious bite problems on the opposite side. I hope
that is your experience, too.Witch hazel is OK to use in ears. It just stings if there is any ulceration
of the ear canal and should be discontinued if signs of pain occur when
using it. Diluted vinegar can also sting but is a little less likely to do
so.I suspect that you are correct that the ear problems are related to changes
in the ear canal, or possibly middle ear drainage or pressure equalization,
postsurgically. It may be necessary to use antibiotics or topical therapy
on a semi-regular basis to control this problem in the future, if these
changes make it easier for bacteria or yeast to grow in the ear. It is OK
to do this, if necessary. I am not a big fan of ear cultures but lots of
vets believe they are helpful and I do find myself doing them occasionally,
too. Using something to keep the ear environment unfriendly to yeast and
bacteria can help prolong the interval between infections. Witch hazel and
vinegar/water combinations should be helpful. I think it is worth doing
these things since I think that the benefits outweigh the risks but your
vet may have different clinical experience with this. I can't say I can
prove scientifically that I am right, it is just an observation based on my
patients.Hope this helps.
Mike Richards, DVM
2/11/2000
Bone cancer (osteosarcoma) or Bone infection (osteomyelitis) and Rapid respiration
Question: Hi Dr. Mike,
I am a subscriber who wrote you about a month ago about my large mixed breed
(90 lb male 10 years old (lab, border collie, newf?) dog (Noah) who was
having rapid respirations (avg. 60 to 70 per minute; has been as high as 90
and as low as 40) but no other symptoms. At the time we thought it was
bronchitis. This has been going on for about 10 weeks. Tests have ruled out
Cushings. Low thryoid problems were found (very very low according to our
vet) and he has been put on thyroid medication but this has not done anything
to help respirations. Please note, he is not panting. These rapid
respirations occur whether awake or asleep with mouth closed. He can't
tolerate exercise and gets tired very easily. We went to a specialist last
Thursday. He said x-rays clearly showed lung disease but not bronchitis but
problems with the connecting tissue of the lung. He also noted a possible
problem with the breastbone that showed up on the x-rays (3 sets taken about
2-3 weeks apart). He thought perhaps there was infection going on or
possible cancer. (In the bone sections which were squard off, there was a
section that was rounded and smaller than the others.) A bone marrow biopsy
was done along with a bronchial wash. We will get the results by September
12th. In the meantime Noah has been put on 3000mg per day of Keflex. He is
still showing no signs other than the rapid respirations and being tired all
the time. Oh, and high akaline phophostates (?) - not new, he has had this
problem off on on for about two years. Can you give us any idea what might
be in store for us? Infection or worse yet, cancer. Treatment advise, etc.
Other info we can find on bone infection talks about long term recovery,
high fevers, vomitting, etc. so we are concerned.Your information is always wonderful and I am very grateful that you provide
this service. Any information or thoughts you could give would be very much
appreciated.Thank you. Brenda
Answer: Brenda-
There are two likely possibilities suggested by the specialist, bone
infection and bone cancer. If the first set of X-rays did not show a
problem or if they showed a problem that is worse on the second set of
X-rays, then there is no need to consider the other possibility that I can
think of, which is a birth defect that hasn't been detected until this time
because it wasn't causing any problems.There are several possible bone cancers and the prognosis is quite
different, depending on which one is present.The most common form of bone cancer is osteosarcoma. These are very
invasive and highly malignant tumors that usually occur in the bones of the
legs but can occur in any bone. Approximately 90% of bone cancers are
osteosarcomas.The second most common form of bone cancer is chondrosarcoma. This tumor
usually occurs in flat bones, such as the ribs. This is the form of bone
cancer that has the best prognosis. If it is possible to remove the
affected bone and a wide margin around it, the long term survival rate
after surgery is pretty good, an average of three years or so. Even though
this tumor represents less than 10% of the bone cancers it may be more
likely in this case, due to the location.There is a pretty rare form of bone cancer known as a multilobular
osteochondrosarcoma that usually affects the skull bones. This type of
cancer often recurs at the site that it is removed and can metastasize to
other tissues but most dogs that have these tumors live for a two to three
years after surgical removal.The other cancers that involve bone are tumors that arise in other tissues
and then spread to the bone. Tumors that can do this include
hemangiosarcoma, lymphoma and fibrosarcomas. These tumors tend to be
identified in other tissues prior to showing up in bone but we have seen
one case of lymphoma where the first sign of problems was lameness from
bone invasion and a couple of fibrosarcomas that seemed to arise directly
from bone or from tissue very closely associated with bone.Bone infections are not common, but do sometimes occur. We sometimes see
bone infections underlying areas in which there is a lot of pressure on the
skin when dogs lay down, leading to skin sores, such as the elbow region
and sternum. Bone infections are best treated by culturing the infected
area, identifying the bacteria involved and determining which antibiotics
are likely to work by doing sensitivity testing. Once this lab work is
done, an appropriate antibiotic is given for 4 weeks or more (sometimes
three or four months) until the bone has healed. If there appears to be
bone death (necrosis) from the infection, it is usually necessary to remove
the dead bone surgically prior to using antibiotics, in order to get a
cure. Most of the cases of bone infection (osteomyelitis) will respond to
antibiotics and surgical debridement but there are times when this is a
frustrating condition that requires a lot of effort to resolve. In areas in
which fungal infection of bone occurs, that has to be ruled out, as well.I think you have to wait to see what is found before getting too far into
exploring options. It is likely that you will have viable options for
treatment of whatever is identified, based on the location of the problem
or even that treatment won't seem necessary after the results are in.There are a lot of problems that can lead to rapid respiratory rates. Upper
airway disorders such as nostrils that are too narrow, obstructions in the
nasal cavity, pharyngeal disorders, laryngeal paralysis, tracheal collapse
and tracheal parasites can cause rapid respiratory rates. Lower airway
disorders such as bronchial constrictions (allergic, asthmatic, etc) can
also do this. Heart and circulatory disorders such as heartworms, anemia
and bleeding disorders can lead to increased respiratory rates. Injuries to
the chest, ribs, sternum (including congenital defects) or the abdominal
cavity which cause pain or bleeding can lead to increased respiratory
rates. Things that cause fluid to accumulate in the chest cavity (cancer,
heart disease, heartworms) can raise respiratory rates. I think that pain
alone can do this and that stress probably can. Infections such as
pneumonia, septicemia and probably osteomyelitis can do this. At this
time, many of these problems have probably been ruled out --- but if one of
them seems possible to you, it would be a good idea to ask your vet about it.I hope this helps in thinking over the possible problems.
Mike Richards, DVM
9/10/2000
Bone Cancer - Dilantin and phantom pain
Q: Dr. Mike, My dog is a 12-yr old, 65 lb. mixed breed who underwent amputation of her right front leg due to bone cancer in August, 1996. She recovered nicely but about 6 months after the surgery she began licking her remaining front leg, esp. in the early morning. She has lately been intensifying her efforts, and sometimes the urgent licking is accompanied by little yelps or groans, and she has also begun working on her hind legs, and sometimes also on her bedding fabric. Our vet (the one who did the surgery) thought that she might have some arthritic pain and prescribed anti-inflammatory medication last March. This didn't really have any effect, and after another visit last week, after consulting with a fellow clinic vet, he suggested that we put her on Dilantin, 100 mg, 3 tab BID. He also took chest x-rays and one rear leg x-ray and at this time there still is no evidence of the cancer having spread to the lungs. He said that the Dilantin might help if her condition is related to a phantom nerve condition brought on by the amputation. After researching Dilantin, I am concerned because it seems to be used largely to treat epileptic seizures. I am wondering if you have had experience with this type of reaction in dogs with limbs removed, or if there is any other kind of care or consultation that we might look into. Thank you, Cathy
A: Cathy- I can not find any information on the use of phenytoin (Dilantin Rx) for phantom pain in dogs but that doesn't mean your vet doesn't know something I don't. There are a lot of anecdotal uses for various medications that may appear in just one or two references --- or none at all.
I have not seen this type of reaction after an amputation. Given the reason for the amputation I think I'd still be really suspicious of metastasis of the cancer even though it is not seen on the X-rays. Unfortunately I do not have any better suggestions for treatment. I wish I could help more.
Mike Richards, DVM
Q: I recently wrote to you regarding my parent's german shephard with a diaphragmatic hernia. Thank you for your response. Unfortunately when they opened her up to repair the hernia they discovered instead a large 20cm tumor between her heart, diaphragm and lungs. She tolerated the surgery and is recovering well. We bring her home tomorrow. Unfortunately it is malignant. It is a osteosarcoma. Do you know anything about this type of tumor? Further histology is being done, but apparently it contained bone, fiber, and cartilage cells. The vets feel it probably started in utero as she was developing. They say they have not run into this type of tumor in a dog before and are not sure of the prognosis, except that it is probably poor. Do you have any further information or know of any sources? Thank you. m-
A: Osteosarcomas are a bone origin tumor, usually. German shepherds have a predilection for these tumors,, along with St. Bernard's, great Danes, golden retrievers and Irish setters. These tumors are most common in bone but they have been reported as a primary lung tumor and definitely can metastasize to the lung region from a site in the bone. When this type of tumor is found in the lungs it is a good idea to try to find a primary site in the bone. The major sites these are found are the wrist, shoulder, hock, stifle and hip region.
I wish I knew of a good treatment, but I do not. It is important to be sure of the type of tumor, through histopathology (examination by a pathologist) if at all possible. This has probably been done already but it is good to check. Some tumors are more treatable than osteosarcomas. There are veterinary cancer specialists and it is worth asking for referral to one for the most definite answer as to treatment. They usually know the most up-to-date information on this.
Mike Richards, DVM
Last edited 01/30/05
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