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032708_osametas…atmentsrev2.doc

Treatment for Osteosarcoma Lung Metastasis in Dogs
Metastasis is more common in dogs with appendicular osteosarcoma, hemangiosarcoma, and chondrosarcoma. Metastasis is rare in dogs with axialtumors, except for osteosarcoma of the ribs, scapula or pelvis.1 The diagnosis of osteosarcoma with metastatic disease is historically associated with apoor prognosis for long term survival. One study showed that dogs with a Stage III osteosarcoma (distant metastasis) showed a median survival timeof 76 days, with a range of 0-1583 days with various treatment options including surgery, palliative radiation therapy, and chemotherapy (Boston etal, JAVMA 2006).
In other words, without any treatment, the prognosis for this stage of osteosarcoma is about two months. With treatment, about six months.
Diagnosing OSA Metastasis:
The following diagnostic tests may be performed to grade the severity of the metastasis, and determine the appropriate course of action that canprovide the best overall quality of life for your dog. Tests are listed in order of complexity and depth.
(varies by location)
Chest X-Rays / Radiographs
CT Scan of Lungs with interpretation: CT scans are best at detecting small abnormalities, such as metastatic cancer in the lungs. CT Scans require
general anesthesia and sometimes contrasting agents must be injected into the body to enhance the images. Technetium scan of Legs / Vertebrae and X-Rays of Spine (rarely do people elect to do a full body CT scan for screening the bones due to the cost
and associated anesthesia time) Nuclear Scan or X-Rays of the Long Bones. 8 screening radiographs. (A nuclear scan will light up in areas of the affected bone, then x-rays are
taken to confirm any lesions. Alternatively, you can do the x-rays as a first line to screen for bone lesions) Once confirmed, treatment options for OSA Metastasis include: Surgical removal of lesions in the lung.
Candidates include: Will work if no more than  those with the primary tumor in remission 50% of lung needs to be One study showed the median survival time after surgery alone to be 176 days (range 20 to 1495  only 1 or 2 visible nodules within the chest complications and days) with an overall survival time of 487 days  no other metastatic lesions in the body Recovery time: 2 – 4 days from the time of original diagnosis (O'Brien et al  a long doubling time of the metastatic Vet Surg 1993).
lesions (>30 days) OSA Metastasis Diagnosis and Treatment for Canine Osteosarcoma 2011, Tripawds.com In the metastasis phase of this disease, Standard treatment of one Adriamycin treatment chemotherapy is not very promising.
IV infusion, every 3 weeks is roughly $500 per treatment every 3  One study showed a response rate of 9% with If a dog has not had Adriamycin for metastatic disease previous chemotherapy, according to number of there is a slight chance that treatments  Response rates overall to any chemotherapy at outcomes rates could be the site have been reported to be 2% Also known as "low dose chemotherapy" A Chemotherapy Agent, NSAID and Non-steroidal drugs help Depending on the dog's designed to arrest tumor blood vessel Doxycycline are the three most commonly used keep inflammation down, drugs in metronomic chemotherapy.
which can keep cells inbetter condition and more Cytoxan: varies from The goal of this therapy is not to eliminate the Cytoxan: a chemotherapy agent given every resistant to further cancer disease completely, but to achieve "stable disease" other day. At this low, chronic dose it's been damage, resulting in better month.
to arrest its growth and spread.
shown to inhibit blood vessel growth.
overall health for thepatient.
NSAID: varies from Anti-tumor effects of similar protocols have been nother chemotherapy agent is used in $50 to $100 per month.
proven in laboratory animals and humans with Treatment can be given at advanced, chemotherapy resistant cancer.
many instances, it has shown greater success in Doxycycline; varies treating mets than Cytoxan.
from $30 to $60 per Read More:
Side effects rarely include: month.
Piroxicam: a non-steroidal drug with potent bone marrow suppression, COX-2 inhibiting properties. COX-2 is a and inflammation of the receptor that's been found to play a role in tumor bladder wall (cystitis).
development. In one study, 77% of osteosarcoma There is about a 5% xpressed the COX-2 receptor (Mullins et al chance of this occurring,but a greater risk in female VIM 2005).
Other non-steroidal drugs include the name brands of Metacam, Rimadyl, and Previcox.
CBC blood counts will be Doxycycline: an antibiotic when given at low doses has been shown to inhibit blood vessel This treatment is still formation, which feed tumors. Does not affect undergoing study, the existing tumor(s).
therefore a life expectancyprognosis cannot be given with any certainty.
Fish Oil: The anti-tumor properties proven infish oil supplements are showing promise in metronomic therapy.
OSA Metastasis Diagnosis and Treatment for Canine Osteosarcoma 2011, Tripawds.com diuretic to prevent bladder infectionsy caused by chemotherapy agents, isoften given, especially for female patients.
ome oncologists are usingthis not only to alleviate pain in dogs who aren'tamputation candidates, but becausebisphosphonates (i.e., Pamidronate, Zoledronate)hanlaboratory studies.
There are always ongoing clinical trials that may Many private and public veterinary teaching Among a variety of other Varies. Some trials will be available in their area (usually through hospitals conduct osteosarcoma clinical trials.
requirements, clinical trials cover all costs veterinary universities) and inhalational Visit theo find a can require participant to: chemotherapy (Inhales an pulmonary metastasis clinical Trial near you.
treatment, some will option for pulmonary metastasis.
live within the area partially cover.
agree to having an autopsy Read More:
performed on theparticipating canine agree to a designated number of follow up visitsand tests agree to abide bynutritional exclusions/additions and lifestylerequirements for controlledstudying.
1American College of Veterinary Surgeons Many thanks to Dr. Marie Janson, DVM, DACVIM (oncoln Highlands Ranch, CO for her assistance in this documentation.
OSA Metastasis Diagnosis and Treatment for Canine Osteosarcoma

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