Episode 157: Canine Cancer

We're joined by Dr. Steve Shaw, a veterinarian and advisor for Oncotect, a company that provides non-invasive cancer screening for dogs. Learn about Dr. Shaw's background in canine oncology, how prevalent cancer is in dogs, why cancer prevalence is increasing, and what makes a dog more likely to develop cancer.

Podcast Transcript:

Nicole Engelman  00:04

Welcome to the Good Dog Pod. Join us every other Wednesday when we discuss all things dogs, from health and veterinary care, to training and behavior science, as well as the ins and outs of Good Dog and how our platform can help you successfully run your breeding program. Follow us and join Good Dog's mission to build a better world for our dogs and the people who love them.

Dr. Nate Ritter  00:28

Hi, everyone, and welcome back to another episode of The Good Dog Pod where we discuss all things related to Canine health. Research. How Good Dog helps breeders when their breeding programs and so much more. I'm Dr. Nate Ritter, the staff veterinarian here at Good Dog and your host for this week's episode. I'm very excited to introduce the topic of today's podcast canine cancer and veterinary oncology. I'm joined this week by Dr. Steve Shaw, Dr. Shaw earned his veterinary degree at UC Davis in 2004. He then did a rotating internship at Veterinary Medical and Surgical Group in Southern California and returned to UC Davis completing his residency in Small Animal Medical Oncology in 2009. He has since been practicing clinical oncology at Sage Veterinary Centers in Northern California Silicon Valley. Dr. Shaw was also a co-founder and Managing Partner at Vet Prep, an online board review program developed to help veterinary students study for and pass their national licensing exam, the NAVLE. He is also currently an advisor for Oncotect, a company that has developed a non-invasive cancer screening test for dogs that uses urine collected from home. He enjoys skiing, hiking, traveling, and spending time outdoors with his partner and their two dogs, an Australian shepherd named Charlie and a pitbull mix named Tucker. Dr. Shaw, welcome to the Good Dog Pod.

Dr. Steve Shaw  01:37

Hi, thanks for having me.

Dr. Nate Ritter  01:39

Yeah, absolutely. So I thought we'd start if you could give us just a little bit about your background, how did you become interested in veterinary medicine? And then specifically, what drove you to oncology?

Dr. Steve Shaw  01:48

Yeah, so I think probably similar to a lot of vets, I grew up loving animals and wound up having quite a few pets as a kid. As I got older, I found out that I really liked biology and was pretty good at it. You know, I continued with my education through college, I wound up doing some volunteer work with Wildlife Rehab, and working with some lab animals in school. And it seemed like a really good fit, because I was really interested in medicine at that point, and biology and you know, just really wanted to do something productive for the community and for pets and people. So it was a pretty natural fit, kind of a no brainer.

Dr. Nate Ritter  02:34

Yeah, absolutely. And then what specifically to oncology? Did you figure that out in undergrad or in veterinary school, or where did that happen?

Dr. Steve Shaw  02:43

So after my first year of vet school, at Davis, they allow some of the underclass students to participate in some of the clinics. And the first one that I did right after my first year was in oncology. And the resident that I was working with was really influential for me, and really got me, you know, into clinics and seeing how dedicated the pet owners are in oncology. And I think, you know, a lot of what we do is palliative type care, and making sure that the pets are feeling good, and maintain a good quality of life and such. And I really liked that idea of making sure that these dogs and cats that tend to be older, and you know, further along in age, that they can still have a good quality of life when it comes closer to the end of their lives. So that was a big, big draw for me. And yeah, really just the client base that I have, they all tend to be just very dedicated to their pets.

Dr. Nate Ritter  03:45

No, that's for sure. And what did that path involve? I think a lot of people obviously know, undergraduate veterinary school, what internships residency, kind of tell us about that path, because I don't think people always understand or appreciate, you know, the dedication and the time that it takes to become board certified in a specialty.

Dr. Steve Shaw  04:02

Yeah, it was a little bit of a journey. So I did my undergrad at UC Berkeley. And then after finishing that, it is required to have quite a bit of hands-on animal experience in order to apply to vet school. So I wound up taking some time, a couple years actually to work in a vet clinic, doing some tech work and kind of assistant type work, just gaining experience and making sure that it was the right fit for me. And after you know, getting into vet school, vet school winds up being four years to get your degree. After that an internship is optional, but I wound up doing an internship which just gives you more experience. It's a pretty intensive year of doing a little bit of everything, rotating through different specialties and just kind of honing your skills a little bit more before you're led out to practice on your own. So I did that and then I went back for the residency which was a three year program at Davis. And all along the way you're taking exams to make sure that you're up to snuff.

Dr. Nate Ritter  05:10

Yeah, very cool. So speaking of cancer, I think our audience does appreciate the prevalence, but I think even so might not know just how common it is. I was wondering if you could speak to that, particularly in dogs. 

Dr. Steve Shaw  05:22

So, it really is quite prevalent in dogs, probably a similar kind of prevalence to people. So the statistic is that dogs that are older than 10 years of age have about a 50% chance of developing cancer. And about a quarter of dogs wind up dying of cancer. So it's quite common.

Dr. Nate Ritter  05:44

Yeah, definitely. Has this prevalence increased over time? Is it something that you've started to appreciate? I know, a lot of people speak to this. Is it because we're better at detecting cancer? Is it because dogs are living longer? And eventually, unfortunately, everything must pass from something a combination of it all?

Dr. Steve Shaw  06:04

Right, I think it's a little bit hard to say for sure what the prevalence is changing? I think what you said is exactly right. And that, you know, it's probably a combination of all these things where the tests out there are getting better at detecting cancers earlier. And as we develop more medications for different types of diseases, dogs are living a bit longer. And the longer they live, the more time they have to wind up developing other issues like cancers. And so it really is something that I think is a lot more common than what people would imagine.

Dr. Nate Ritter  06:42

Yeah, absolutely. What makes a dog more likely to develop cancer? I know you spoke a little bit to the age and the statistics there, but just generally breed type different things of that nature.

Dr. Steve Shaw  06:54

Yeah, so I think a really big component of why dogs develop cancer would be genetics. We know this, because there are certain breeds that are a lot more prone to developing certain types of cancers. You know, besides genetics, there can be some environmental factors as well. Certainly, there have been some studies that looked at using herbicides and pesticides that have increased the risk for cancers in dogs. There are also certain diseases that can kind of predispose you know any animal to increase risk for cancer. So being immunocompromised would increase your risk. We see that quite commonly in cats with FIV and FeLV. It's not quite as common in dogs in terms of seeing them being immunocompromised and having a direct link to developing cancer, but we know that that's the case. And also having chronic inflammation can certainly do it as well.

Dr. Nate Ritter  07:51

Talk to us a little bit about some of the most common types of cancers. I know a lot of our audience is probably familiar with some but I still think it's, you know, interesting to talk about all the different types.

Dr. Steve Shaw  08:01

Yeah, so probably, you know, the most common cancer that I treat in the clinic is lymphoma. So lymphoma being cancer of the lymphocytes, typically, most commonly will develop in the lymph nodes. So owners will feel lumps around the neck and in the shoulder area, behind the knees, in the groin, those are the areas where the lymph nodes live, that are kind of most easily found. So lymphoma is a real common one. Mast cell tumors are the most common type of skin cancer that we see in dogs, those can show up, you know, anywhere on the body pretty much and can kind of look like anything. They're called the ‘great pretender’ because they can show up looking like various things, which kind of speaks to the idea of just making sure you try and aspirate and get a sample of these things as they pop up. Other types of tumors, soft tissue sarcomas are pretty common. Those also tend to show up as lumps under the skin on dogs. Hemangiosarcoma, which is a really insidious disease that usually appears in the spleen, but can also show up in other organs as well. It's very common in Retrievers, and German Shepherd dogs and Boxers. And then for the large and giant breed dogs, osteosarcoma is one of the really big ones where it's cancer of the bones.

Dr. Nate Ritter  09:28

Yeah, so I know you touched on briefly before, if you could talk a little bit about the difference in veterinary and human oncology in terms of your approach to patients and treatment plans and what have you.

Dr. Steve Shaw  09:40

Yeah, that's a great question. So the biggest difference is just our philosophy and how we approach treating dogs. You know, for a human they typically will give very, very high doses of treatments like chemotherapy and radiation, to basically try and cure them of the disease and in doing so they can make them really sick. And people can oftentimes pass away as a result of complications from treatments like chemo and radiation. In dogs, we feel like, you know, it's not their choice, and they don't fully understand the whole process. So we want to make sure that they have a good quality of life. And that's going to be the most important thing for them is that they feel normal and feel as good as possible. And so when we do things like chemo and radiation, we really keep those things in mind. And we wind up using much lower doses of these treatments, compared to what a person goes through, and really focus on their quality of life and just making sure that they're not having unacceptable side effects and such. So it's always a big conversation with the pet parents to make sure that they're aware of what the risks are and what some of the expectations should be. So just making sure that everyone's on the same page in terms of expectations.

Dr. Nate Ritter  11:03

Absolutely, and I think that's such an important point. It's one that I think a lot of people think of being a good pet parent by willing to go to the ends of the earth for their animal, which you know, in some cases, it might not always be the appropriate things speaking to quality of life, they don't understand what's happening to them in the treatments that may be involved. So it's definitely more complicated than it's made out to be. For owners, we're talking about diagnosis, and then treatment we've kind of talked about a little bit. What can they do in the meantime? I know your association with Oncotect, this screening is relatively new technology. You know, I'm more familiar with the screening that can be done in the clinic and this at home technology utilizing urine. I think that's so fascinating. I was wondering if you could speak to that a little bit.

Dr. Steve Shaw  11:46

Yeah, so I do advisory work for Oncotect, and it's basically a test that looks at urine, and the urine can be collected from home by the pet owner, and then shipped out to the company. They'll run the testing on it, and then they're basically looking for volatile compounds that are in the urine that occur in animals and people with cancer. And depending on what the results show, then they give you a report that tells you whether your pet is at low risk or moderate risk or at high risk. And so some additional kind of confirmatory testing is required afterwards, but it helps to do a general screening. And again, you can do that from home. So it's non-invasive and less stressful overall for the pet. And currently, the tumors that it screens for our mast cell tumors, lymphoma, melanomas, and hemangiosarcoma. So all are very common types of cancers, and we think that there's potentially other cancers that it can detect as well. But those are the ones that have been looked at and proven moreso.

Dr. Nate Ritter  12:57

Very cool. And then outside of some of the screening methods, what other kinds of diagnostics day to day, even if your animals are doing well, what can be done when you go in for your annual to kind of take a look? I think also people sometimes get confused with there isn't necessarily a singular test. So people will say what do you mean, you can't tell me if my dog has cancer or not based on bloodwork, I guess, talking to diagnostics in general, but then also kind of how you hone in on the diagnosis?

Dr. Steve Shaw  12:57

Yeah, well, I think what I would normally recommend for owners at home would be to really just pay attention to any new lumps or bumps that they can feel and then changes in behavior. And so cancer can really show up as any type of symptom or clinical sign. And so it can be a little bit surprising to some people when they find that their pet has been acting totally normal. And then maybe they just had a little bit of blood in their urine, or just some mild changes in their behavior. And it turns out to be cancer, and not to try and make people panicked or scared of, you know, every little difference in what their dog does, as being cancer, it's just, you know, just having to be aware that one, there can be a lot of different causes for blood in the urine or, you know, whatever symptom you might be seeing, but most importantly is to just have it checked out if it's something that looks abnormal to you. And in the clinic, so usually we start with general screening tests again. So like bloodwork, urinalysis, and to have a better visualization of what's going on internally, we can take x rays or do an ultrasound of the abdomen. And if it requires more kind of specific, more advanced imaging, then we can do things like CT than MRIs to get a better look. But ultimately, it's not what we can really just see or feel from the outside. I think the gold standard in being able to diagnose the cancer is to actually take a sample of it. So that would mean either a fine needle aspirate or like a needle biopsy, which is usually pretty simple, or taking an actual chunk of tissue, which would be an actual biopsy.

Dr. Nate Ritter  13:32

Now switching lanes a little bit, I wanted to ask you, because I thought it was so cool that you were involved with vet prep from the very beginning. And it's something that I used when studying for the NAVLE which is the North American Veterinary Licensing Exam. What drove you to getting involved? How did this come to be? I think it's so cool.

Dr. Steve Shaw  15:31

Yeah, well, thanks for using. So yeah, it was a fun kind of time for me. When I was a senior student in vet school, this was way back in like 2004. And we were studying for our NAVLE. It was me and a couple of friends in my class who used to always study together. And one of my buddy's, his girlfriend, at the time, was a medical student at Davis, and she was studying for her boards at the same time. And she had this online program that was available to them. And it was this really cool program that really helped them to pinpoint their studies and such and gave them practice exams. And we're just like, well, why don't we have anything like that, we were basically studying out of all of our class notes. And the Merck manual, which for people that don't know is basically a dictionary of every animal disease under the sun, and was pretty tedious to go through that. So we thought that we could do something similar for vets. And so we wound up starting it during our senior year of vet school and started writing questions. And you know, having all of them looked at by specialists that were at Davis with us, and built this database of questions. And I happen to have a friend who was a software developer who helped us build the whole program from the ground up. And it took about two years or so to get everything off the ground and for the database of questions to be big enough for us to launch it. And so it was originally meant to be just kind of like a cool project for us friends to, kind of work on together, because we like working together. And we're good friends. And so it was just kind of like this fun project. And then it turned out to be this really quite effective, popular and very useful study tool that just, you know, went viral around the country. And it turned out to be, you know, a much bigger endeavor than we had imagined. And we're real happy with it. And proud of it. And yeah, it's a big part of my life for 16 years. And we wound up selling the company at one point. But yeah, so very proud of what we did.

Dr. Nate Ritter  17:50

Yeah, as you should be. And I thank you for doing that. It certainly made my studying a little more focused and easier. Great. Well, that's all we've got for today. Thank you so much for taking the time to tune into this week's episode. We'd also like to thank Dr. Shaw and Oncotect for your time and willingness to educate our community. We hope this information was helpful for everyone. We appreciate you tuning in and we'll see you back here for our next episode.

Nicole Engelman  18:11

Thank you for listening to the Good Dog Pod. We'll be back in two weeks with another episode so be sure to subscribe to the Good Dog Pod on your favorite podcast platform.