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The ASHGI Cancer Survey
First printed in the Aussie Times, November-December 2007
by C.A. Sharp, President and Lizette Busquets, Cancer Committee Chair
| On Christmas Eve, 2006, Ray put
Blue on the table for his weekly
grooming. When he finished
brushing his buddy, Ray gave
Blue a quick scruff and a hug. By
chance, he felt the little tumor on
Blue’s sternum. |
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A few days later, Ray and Blue
were at the veterinarian's office.
Ray wasn't very worried about
such a small lump, but he wasn't
taking chances with his heart dog. The
tumor was so tiny Dr. Leone couldn't find
it. It took Ray ten minutes to locate it in
Blue's dense winter coat to show him. Dr. Leone decided to do a needle
biopsy. Afterwards, Ray and Blue went
to the reception area to await results. A
few minutes later Dr. Leone came out, his
face somber. Abnormal cells in the sample
made him suspect cancer. He recommended
removing the tumor. Ray said he'd see the
receptionist to schedule the surgery.
Dr. Leone shook his head. "I think we
should do it today."
Ray left his best buddy in the clinic’s
capable hands, but went home with a
heavy heart. Blue's mother had died
of hemangiosarcoma. A littermate had
succumbed to melanoma. Six close
relatives had died of lymphoma. A
week later the pathology report came
back from the university lab: Blue had
hemangiosarcoma.
The Australian Shepherd Health &
Genetics Institute, Inc. (ASHGI) conducted
its first health survey, focused on cancer,
from January 2006 through January
2007, with follow-up contacts with select
respondents made through May of 2007.
There had been two prior general health
surveys of the breed: A small private effort
conducted by Leos Kral, PhD, of West
Georgia State University in the mid-1990s
and a larger project mounted by the DNA
& Genetics Committee of the Australian
Shepherd Club of America in 1999. Those
surveys and a breed longevity study
undertaken by the late John B. Armstrong,
PhD, of the University of Ottawa, indicated
that cancer might be a more significant
issue for Australian Shepherds than was
generally realized. Therefore, ASHGI
decided at the time of its formation in 2001
that a cancer-specific survey would be
conducted as soon as the organization had
grown sufficiently to undertake the effort.
In early 2006, ASHGI contracted with
Matrix Canine Research Institute (MCRI)
of Shallowater, Texas for technical support.
MCRI's principal, Scot Dowd, PhD,
produced the Web version of the survey.
MCRI hosted the survey and maintained
the data on their server during the course
of the survey.
ASHGI also prepared a paper version
of the survey form for those who did not
have web access. The survey was advertised
in both the Aussie Times and the Australian
Shepherd Journal and heavily promoted on
breed discussion lists.
ASHGI’s goal was to determine which
cancers, if any, were common in the breed
and whether any environmental factors
appeared to be significant. If any types of
cancer proved common, it would follow up
with a closer examination of those types,
seek out researchers and, where necessary,
raise funds for research. While the survey
design, by focusing strictly on dogs that had
cancer, cannot provide frequency statistics,
we feel it did give us a good idea of what
cancers Aussie owners and breeders most
need to beware of.
Who Responded
The survey was open to any Aussie with
cancer, without regard to registry or country
of residence. Response was international.
The great majority of responses came from
the United States but 7.3 percent were
from elsewhere. Over half of those were Canadian and most of the rest were from Europe. A few came from other parts of the
world (Australia, Japan, New Zealand, and
South Africa). Overseas response might
have been higher had we been able to
mount the survey in multiple languages, as
most of the non-U.S. countries were either
English-speaking or have a significant
number of people fluent in the language.
A total of 534 dogs were entered
in the survey. Almost all (92 percent)
were considered pets. Many were active
in competitive events (36.7 percent
conformation, 40.3 percent performance
events), with about a third of those dogs
active in both. Fourteen-and-a-half percent
of the dogs were stockdogs, 1.3 percent
search-and-rescue, and 6.5 percent listed various other occupations, including therapy dog.
Cancer in Aussies
When designing the survey, we
developed a list of cancers drawing largely
from types known to appear frequently in
dogs as a species. We made sure to include
those for which author Sharp had previously acquired data on multiple cases. The survey
results indicated that most cancers were
not common enough to indicate a problem
specific to our breed, but two stood out:
Hemangiosarcoma and lymphoma [see
Table 1.] Some of the cancers listed in the
"other" category might have fallen into one
of the categories named above. However,
the respondents either did not remember or
did not know the precise diagnosis. As an
example, 11.7 percent were listed as "liver"
and 5.3 percent were listed as "lung". Both
sites are common for hemangiosarcoma
tumors and primary lung cancer is rare in
dogs, so the actual number of dogs with
those particular cancers may have been
higher.
| Table 1: Cancers Reported |
| Hemangiosarcoma |
26.4 |
| Lymphoma |
16.8 |
| Mammary |
5.7 |
| Mast Cell |
5.7 |
| Osteosarcoma |
5.7 |
| Soft Tissue Carcinoma |
5.4 |
| Squamous Cell Carcinoma |
2.6 |
| Basal Cell Carcinoma |
1.3 |
| Leukemia |
0.77 |
| Melanoma |
0.26 |
| Various Others |
23.1 |
Average age at diagnosis was 9.2 years,
with almost all of the diagnoses being
made between 6.4 and 12 years, so cancer
in Aussies appears to be largely a disease
of middle-aged and elderly dogs. Cancer
in juvenile and young adult dogs was rare.
Survival among submitted dogs was poor,
with 74.4 percent of the dogs having died
because of the disease. A total of 47.6
percent dogs suffered from metastastic
disease in which the cancer had spread
from the primary tumor to other organs;
17.9 percent were reported as having a
period of remission. [For similar statistics
on hemangiosarcoma and lymphoma, see
Table 2.]
| Table 2: Comparitive Statistics |
| |
Hemangiosarcoma |
Lymphoma |
All Others |
| % of total |
26.4 |
16.8 |
56.8 |
| Av age at Diagnosis (yrs) |
9.5 |
7.7 |
9.1 |
| % Remission |
17.8 |
13.3 |
21.6 |
| % Mestasis |
63.7 |
43.0 |
41.9 |
| % Died due to Cancer |
80.0 |
77.4 |
74.4 |
Gender did not appear to be a factor in the development of cancer: Roughly half the dogs submitted were male and
half female. Most (70 percent dogs, 74.3
percent bitches) were altered. Since altering
of pet and retired dogs is common, this may
not be significant. However, we will look
at altered status and age of altering more closely when doing follow-up on the more common cancers.
When considering the data set as a
whole, none of the reported environmental
factors appeared to have any correlation
with cancer.
The Deadly Duo:
Hemangiosarcoma and
Lymphoma Hemangiosarcoma (26.4 percent) and
lymphoma (16.8 percent) were reported
so frequently that it is probable that these
forms are at least partly inherited in the
Australian Shepherd. Information on cancer
status of the parents of submitted dogs was
not terribly informative, as respondents
often did not know what the parents had
died of or, if it was cancer, they did not
know what type. Even so, 8.9 percent of the
dogs reported with hemangiosarcoma had a
parent that suffered from the same cancer.
Family trends in this cancer and lymphoma
need further study.
The data submitted on environmental
factors further support the supposition that
Aussies may have a genetic predisposition
to these two cancers. With one exception,
there was no significant correlation between
environmental factors and either cancer.
The exception to that trend was
with lymphoma and spraying programs:
18.5 percent of Aussies with lymphoma
were also reported to have had exposure
to urban or rural spraying programs.
This is 55.5 percent greater than the
percentage reported in the full data set.
These results are not conclusive evidence of
a connection between the two, but it bears
investigation.
Screening and Research
Initiatives
There is already a minimally invasive
early screening and diagnostic blood test
available in the U.S., Canada and the United
Kingdom for lymphoma. It is offered by
PetScreen, a UK-based company. [See
"Canine Cancer Internet Resources."] This
test can be used to monitor status of dogs
with a familial risk for lymphoma and also as a diagnostic tool for dogs presenting signs of possible lymphoma. There are at present
no similar tests for hemangiosarcoma, nor
are there genetic screening tests available
to determine carrier status for either type.
On the research front there are a
number of studies underway or planned
exploring better diagnostic techniques,
improved treatments and the genetic
aspects of cancer. Many studies are specific
to a particular breed or group of breeds.
There are none at present that focus on
Australian Shepherds, though there are a
few that accept any dog with the type of
cancer they are targeting.
More investigation of canine cancer is
needed. To encourage additional research,
the two major U.S. granting agencies that
support canine health research, the AKC
Canine Health Foundation and the Morris
Animal Foundation, have joined together
to support a national canine cancer tissue
bank. This bank will maintain tissue
samples from dogs with cancer so they
can be available to researchers as the need
arises. The CHF/MAF partnership has
already attracted a $1.1 gift from Pfizer
Animal Health.
Each organization also provides grants
to specific cancer projects. MAF President/
CEO, Patricia N. Olson DVM PhD said,
"We are all working well together, on
similar issues of great importance and
concern, as we should be!" MAF’s Canine
Cancer Campaign will be aimed not only
at building the tissue bank, but toward
the development of new treatments and
preventing cancer through investigation
of the environmental and genetic risk
factors faced by different breeds. They have
gathered together 14 different veterinary
institutions which will work cooperatively
on canine cancer issues. MAF has received
a gift of $1 million from the Golden
Retriever Foundation for cancer research,
with an emphasis on hemangiosarcoma and lymphoma – the same two cancers that we
in Aussies most need to worry about.
"We’re proud to partner with these
stellar organizations who share our
commitment and mission of helping dogs
live longer, healthier lives,” said CHF
President Wayne Ferguson. CHF Grants
committee member, Dr. Duane Butherus
stated, "Canine cancer ranks as the number
one natural killer of dogs. . . . We're proud to
sponsor this repository and I’m convinced
that it will significantly increase the efficiency and accuracy of cancer research
by quickly providing well-characterized
tissue samples to researchers." CHF has
also received a major gift toward this effort
from the Laura J. Niles Foundation. Where Do We Go from Here?
ASHGI will continue to collect data
on hemangiosarcoma and lymphoma, seek
interested researchers, and form alliances
with other breeds that have a problem with
either of these cancers. ASHGI has already
given $1,000 each to MAF and CHF for
their recently announced cooperative
cancer fund drive.
However, ASHGI can't work alone. We
need the support of the Aussie community.
People must continue to provide us
with information on Aussies with either
hemangiosarcoma or lymphoma. Educate
yourselves about these cancers. If you
have an Aussie who has relatives with
lymphoma, make use of the PetScreen test.
When cancer research that addresses our
common cancers is identified, support those studies with samples and data. Contribute to
fundraising campaigns for canine cancer.
With luck and quick action, happy
endings can happen. If we focus more time
and resources on supporting research into
the diagnosis, treatment and genetic origins
of cancers, especially hemangiosarcoma
and lymphoma, more dogs like Blue may
be saved from a terrible death. Two weeks after Blue's surgery, Ray
noticed swelling at the tumor site. Soon
after, Dr. Leone removed a larger area
of tissue from Blue’s chest. When the
pathology report came back, no cancer cells
were found in the margins of the sample.
Ray knows the importance of
supporting research on this deadly disease.
He has enrolled Blue in a long-range study
of hemangiosarcoma being conducted
by Colorado State University. Their
preliminary findings indicate that when
the hemangiosarcoma tumors develop
under the skin and surgery is done before
metastasis, the survival rate is high. Today,
almost eight months after being diagnosed
with a cancer that is usually fatal in short
order, Ray's heart dog, Blue, is still alive
and well with no recurrence of the cancer.
(Thanks, Ray and Blue, for sharing your
story.)
Canine Cancer Internet Resources
Hemangiosarcoma
PetPlace.com: "Hemangiosarcoma In Dogs"
www.petplace.com/dogs/hemangiosarcoma-in-dogs/page1.aspx
PetEducation.com: "Hemangiosarcomas"
www.peteducation.com/article.cfm?cls=2&cat=1638&articleid=441
Veterinary Clinical Pathology Clerkship Program: "Canine Hemangiosarcoma," by
Rebecca Frankhauser DVM et al.
www.vet.uga.edu/vpp/clerk/frankhauser/index.php
Lymphoma
PetEducation.com: "Lymphomas"
www.peteducation.com/article.cfm?cls=2&cat=1638&articleid=459
SEVAGrreat.org: "Lymphoma," by Anita Weidinger DVM
www.sevagrreat.org/k9stuff/vetcorner/lymph.htm
VeterinaryPartner.com: "Lymphoma in Dogs," by Wendy C. Brooks DVM
www.veterinarypartner.com/Content.plx?P=A&A=575
PetScreen Lymphoma Test
http://www.pet-screen.com/web/PETSCR/index.cfm
ASHGI Cancer Page
www.ashgi.org/articles/cancer.htm
Canine Health Foundation on the tissue bank
www.akcchf.org/news/index.cfm?article_id=183
Morris Animal Foundation Canine Cancer Campaign
www.morrisanimalfoundation.org/k9_cancer
Survey Committee
ASHGI president, C.A. Sharp, tapped Liz Busquets, an Aussie owner and human cancer
researcher at the University of Notre Dame, to serve as survey chairperson and perform
the statistical analysis. In addition to Sharp, the committee also included ASHGI board
members Kylie Mynyard, PhD of Curtin University of Technology, in Australia, and
George Johnson, PhD, of Arkansas Tech University, along with Claire Gustafson and
Heidi Mobley. When a draft survey was ready, additional review and comment were
provided by Sally Josselyn, Erika Maurer, Lisa McDonald, Kim Monti, and Kristin Rush.
Outside beta testing of the survey format was performed by Charlene Benjamin.
Thank you!
ASHGI would like to thank:
• Scot Dowd of Matrix Canine Research Institution for his efforts on the web version of
the survey, and…
• The hundreds of people who took the time to fill out the survey. We recognize the
personal emotional toll those entries represent and the hundreds of dogs whom
cancer sent over the bridge. We quite literally could not have done this without your
support.
Afterward
Shortly after the completion of the survey, ASHGI set out to find canine cancer research projects that could be beneficial to Australian Shepherds. Within a few months of the survey’s completion they had identified two, both at North Carolina State University.
In the fall of 2007, ASHGI teamed with the Morris Animal Foundation to fund a study of epigenetic activity in lymphoma, our breed’s second most common cancer, with a goal of improving the long-term cure rate for this usually fatal cancer. Epigenetic effects are part of the process of gene regulation – which genes get turned on or off in any given tissue. Understanding gene regulation is vital to the development of better cancer treatments.
The lymphoma study does not need samples from affected dogs, however there is another study that ASHGI is supporting which does, also at NCSU. ASHGI representatives made contact with Dr. Matthew Breen at the 2007 Canine Health Foundation Parent Club Conference. Dr. Breen agreed to add Aussies to his on-going study of hemangiosarcoma, our #1 cancer, lymphoma and other soft-tissue sarcomas. ASHGI is providing both financial support, through CHF, and logistical assistance. For more information on how you and your dog can participate in this study click HERE.
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