Nav: Home

Complete removal of tumor reduces risk of recurrence of cancer in dogs

May 14, 2019

CORVALLIS, Ore. - The relative risk of a recurrence of cancer is reduced by 60% in dogs whose tumors are completely removed, a new analysis by Oregon State University researchers has found.

The researchers reviewed published veterinary studies and found a recurrence of less than 10% in dogs where the soft tissue sarcoma was completely excised, versus 33% recurrence in cases where the cancer was incompletely excised, meaning there was microscopic evidence that tumor cells remained after surgery.

"You want to get all of the tumor out if you can," said Milan Milovancev, an associate professor of small animal surgery in the Carlson College of Veterinary Medicine and lead author of the study. "That's what most veterinarians, including myself, have thought, but this makes it more official. Now we can say, here's the data."

The findings were published recently in the journal Veterinary and Comparative Oncology. Co-authors are Veronica Irvin, an assistant professor in Oregon State's College of Public Health and Human Sciences; Katy Townsend, an assistant professor in the Carlson College of Veterinary Medicine; and Joanne Tuohy of Colorado State University.

The study is a meta-analysis - an analysis of existing studies, used to identify overall trends - of canine soft tissue sarcoma. Meta-analyses are not common in the relatively young field of veterinary medicine research, but likely will be used more as the field moves toward more evidence-based research practices, Milovancev said.

The body of research on removal of soft tissue sarcoma in dogs offered conflicting information to veterinarians, which made the topic a good one for a meta-analysis. Milovancev approached Irvin, a public health researcher, for assistance with the study because these types of studies are much more common in human health research.

"Meta-analysis is seen as the best science," said Irvin, whose research interests include transparency in reporting scientific research and outcomes. "This kind of work fits with mine because it raises questions about how we make veterinary medicine more transparent and rigorous."

A meta-analysis provides researchers the opportunity to combine data from multiple studies and increase statistical power of the findings, uncovering results that could be missed in any of the smaller, individual studies.

The researchers reviewed 486 research articles, ultimately focusing on 10 studies that met a set of criteria for inclusion in the analysis. Those studies represented 278 dogs surgically treated for cases of soft tissue sarcoma.

The researchers found that removing the cancer with microscopically complete surgical margins reduced the risk of recurrence by 60%. Having a better understanding of the benefit to the patient of complete removal of the tumors can help veterinary surgeons better prepare for surgery.

In addition to the clinical findings, the analysis also highlighted the need for researchers in veterinary medicine to adopt standardized research guidelines like those used in human health research in an effort to reduce systematic bias, Irvin said.

In their review, the researchers also assessed each study for risks of bias in the study design. They found that risk of selection bias and detection bias were low but risk of performance bias and exclusion bias were high.

Performance bias is the systematic difference in treatment and care of animals based on their participation in the study; knowing whether an animal had had a complete or incomplete excision of a tumor could subconsciously influence a surgeon's performance. Exclusion bias is the systemic difference in accounting of the animals, such as how many participated, how many withdrew from the study or whether the animals completed follow-up care.

These kinds of biases are typically mitigated in human clinical trials. Adopting standardized methods for conducting studies and reporting data in veterinary medicine, like those used in human clinical trials, could help to ensure bias elimination, the researchers suggested.

Milovancev said the findings from the meta-analysis are already influencing his work; he's changing his approach to study design for his future research in an effort to align it more closely to the design of human trials and reduce bias.

"I'd like to do additional meta-analyses like this, as well," he said, "with the goal of further improving the quality of the science and the quality of care of our furry family members."
-end-


Oregon State University

Related Cancer Articles:

Cancer mortality continues steady decline, driven by progress against lung cancer
The cancer death rate declined by 29% from 1991 to 2017, including a 2.2% drop from 2016 to 2017, the largest single-year drop in cancer mortality ever reported.
Stress in cervical cancer patients associated with higher risk of cancer-specific mortality
Psychological stress was associated with a higher risk of cancer-specific mortality in women diagnosed with cervical cancer.
Cancer-sniffing dogs 97% accurate in identifying lung cancer, according to study in JAOA
The next step will be to further fractionate the samples based on chemical and physical properties, presenting them back to the dogs until the specific biomarkers for each cancer are identified.
Moffitt Cancer Center researchers identify one way T cell function may fail in cancer
Moffitt Cancer Center researchers have discovered a mechanism by which one type of immune cell, CD8+ T cells, can become dysfunctional, impeding its ability to seek and kill cancer cells.
More cancer survivors, fewer cancer specialists point to challenge in meeting care needs
An aging population, a growing number of cancer survivors, and a projected shortage of cancer care providers will result in a challenge in delivering the care for cancer survivors in the United States if systemic changes are not made.
New cancer vaccine platform a potential tool for efficacious targeted cancer therapy
Researchers at the University of Helsinki have discovered a solution in the form of a cancer vaccine platform for improving the efficacy of oncolytic viruses used in cancer treatment.
American Cancer Society outlines blueprint for cancer control in the 21st century
The American Cancer Society is outlining its vision for cancer control in the decades ahead in a series of articles that forms the basis of a national cancer control plan.
Oncotarget: Cancer pioneer employs physics to approach cancer in last research article
In the cover article of Tuesday's issue of Oncotarget, James Frost, MD, PhD, Kenneth Pienta, MD, and the late Donald Coffey, Ph.D., use a theory of physical and biophysical symmetry to derive a new conceptualization of cancer.
Health indicators for newborns of breast cancer survivors may vary by cancer type
In a study published in the International Journal of Cancer, researchers from the UNC Lineberger Comprehensive Cancer Center analyzed health indicators for children born to young breast cancer survivors in North Carolina.
Few women with history of breast cancer and ovarian cancer take a recommended genetic test
More than 80 percent of women living with a history of breast or ovarian cancer at high-risk of having a gene mutation have never taken the test that can detect it.
More Cancer News and Cancer Current Events

Trending Science News

Current Coronavirus (COVID-19) News

Top Science Podcasts

We have hand picked the top science podcasts of 2020.
Now Playing: TED Radio Hour

Teaching For Better Humans 2.0
More than test scores or good grades–what do kids need for the future? This hour, TED speakers explore how to help children grow into better humans, both during and after this time of crisis. Guests include educators Richard Culatta and Liz Kleinrock, psychologist Thomas Curran, and writer Jacqueline Woodson.
Now Playing: Science for the People

#556 The Power of Friendship
It's 2020 and times are tough. Maybe some of us are learning about social distancing the hard way. Maybe we just are all a little anxious. No matter what, we could probably use a friend. But what is a friend, exactly? And why do we need them so much? This week host Bethany Brookshire speaks with Lydia Denworth, author of the new book "Friendship: The Evolution, Biology, and Extraordinary Power of Life's Fundamental Bond". This episode is hosted by Bethany Brookshire, science writer from Science News.
Now Playing: Radiolab

Space
One of the most consistent questions we get at the show is from parents who want to know which episodes are kid-friendly and which aren't. So today, we're releasing a separate feed, Radiolab for Kids. To kick it off, we're rerunning an all-time favorite episode: Space. In the 60's, space exploration was an American obsession. This hour, we chart the path from romance to increasing cynicism. We begin with Ann Druyan, widow of Carl Sagan, with a story about the Voyager expedition, true love, and a golden record that travels through space. And astrophysicist Neil de Grasse Tyson explains the Coepernican Principle, and just how insignificant we are. Support Radiolab today at Radiolab.org/donate.