Have You Ever Wondered About Sarcomas? Meet: Dr. Brittany Siontis, Sarcoma Medical Oncologist at The Mayo Clinic

Meet Dr. Brittany L. Siontis, a medical oncologist with a specialty interest in sarcomas. What are sarcomas? Sarcomas are a rare, insidious, and little-understood cancer that can affect adults and children alike. Often misdiagnosed, sarcomas can begin either in the bones or in the soft tissue. For that reason, they are very difficult to catch in their early stages. Dr Siontis currently serves as the Principal Investigator of several active clinical trials at Mayo Clinic through the Sarcoma Medical Oncology Group and works closely with the non-profit Rein in Sarcoma, a resource for patients and families touched by this disease.

Amy Cohen Epstein: Dr. Brittany Siontis is a medical oncologist with a specialty interest in soft tissue and bone sarcomas at The Mayo Clinic. And to be quite frank, I don't know much about this area of sarcomas and cancer and soft and bone tissue. SoI'm thrilled that you're joining us and telling us more about this because I think it's incredibly important.

Dr. Brittany Siontis: Absolutely. And you are not alone in not being super familiar with bone and soft tissue sarcomas. So I'm always happy to sort of share information about a rare yet very important topic, and something near and dear to my heart. So as you mentioned, I'm a sarcoma medical oncologist at Mayo Clinic, so this is the only type of cancer that I treat. And in truth, even as I was going through my training, I really didn't know a lot about sarcoma. And it was in my oncology fellowship that I ended up spending time in a sarcoma clinic and sort of fell in love with it.

So sarcoma is kind of this very mixed bag group of cancers that come from what we consider the connective tissues of the body — all of the things that hold us together. So we can see sarcomas that come from fat cells, muscle cells, bone cells, because they can come from so many different types of tissues in the body, there are actually over 70 different types of sarcoma. And together, those over 70 different types of sarcoma are less than 1% of cancers diagnosed every year, so that's why most people have never heard about them.

Just to put that into the context of numbers, the American Cancer Society estimates there's going to be about 1.9 million new cancers diagnosed in the United States in 2021. And only about 17,000 of those will be bone and soft tissue sarcomas. While we continue to learn more about cancer in general and cancer-related mortality is in many ways improving, mortality because of sarcoma remains quite high. Part of that is the rarity, difficulty, and delay in diagnosis, as well as the limited treatment options available for these cancers.

Amy Cohen Epstein: And what are the warning signs? Are there any symptoms, signs, that people should know about?

Dr. Brittany Siontis: Yeah, they can be really vague, as with a lot of cancers. But one of the things that we always talk to patients about is a new lump. 99% of the time, a lump is going to be something benign, noncancerous, nothing to worry about. But red flags would certainly be something that is growing over time, something that's greater than a golf ball size. Most of us can picture a golf ball in our head, so that's kind of a nice comparison to make there. Pain is actually a really core discriminator, but certainly, if something is causing pain, we would want patients to go get it evaluated. So those are really kind of the big things that we think about in terms of red flags and things to think about with sarcoma.

Amy Cohen Epstein: And what age group is most affected?

Dr. Brittany Siontis: Any age.

Amy Cohen Epstein: Any age?

Dr. Brittany Siontis: Yeah, any age. So when we look at the adult population, the average age of diagnosis is really in the fifth or sixth decade of life. But we know that can actually really vary from one type of sarcoma to another. So the bone sarcomas are actually much more common in the pediatric and what we consider the adolescent or young adult population — patients that go up to the age of 39. Whereas more of the soft tissue sarcomas, we see more often in the adult and older adult population. But in truth, I've seen patients in their 60s and 70s that have a bone sarcoma, and we've certainly had pediatric patients that have soft tissue sarcomas.

Amy Cohen Epstein: Is the sarcoma related to hemangioma?

Dr. Brittany Siontis: That's a good question. So a hemangioma would be a noncancerous sort of conglomeration of blood vessels. There are vascular sarcomas, or sarcomas that arise from these sort of conglomerations of blood vessels that are separate from hemangioma.

Amy Cohen Epstein: Okay. And who is at risk for this? Who's at risk for bone and soft tissue cancers? Is there a population that's at greater risk, or something that we can do to lower risk?

Dr. Brittany Siontis: The vast majority of these tumors happen for reasons we don't fully understand, which makes it really challenging to do any sort of screening. It's not like breast cancer where we can do mammography, or colon cancer, where we can do colonoscopy for screening. There's no good screening for sarcoma, in part, again, because it's so rare the yield of trying to screen millions of people would be relatively low. Most of these cancers are not genetically associated, so there's no sarcoma gene that we know about at this point that people could potentially pass along to their children. We do know that there are some family cancer syndromes that can increase the risk of multiple different types of cancer including sarcoma, but that is a very small proportion of sarcoma patients that have one of those cancer syndromes.

And then we know there are certain exposures that could potentially increase the risk of developing sarcoma, radiation being one of them. But again, that risk is overall very low, but one we pay attention to in my narrow cancer world nonetheless.

Amy Cohen Epstein: It does have similarities to ovarian cancer. Ovarian cancer is really labeled a rare disease because it affects only about 25,000 women every year. And so I think similarly, the attention, the research funding, the awareness is so different than cancers that affect hundreds of thousands of people every year. Even ovarian cancer, less than 10% are women who have a genetic predisposition. 90-ish percent of the time, it's just one of those things that happen, which is still unexplainable, even after tons of research has been put into it, which is so frustrating. How do you deal with that?

Dr. Brittany Siontis: It is frustrating. It's very frustrating. And I think that frustration is one of the things that drives myself and other providers who treat patients with sarcoma to try and learn more about these cancers so we can counsel our patients with more data. But you're right, it is a rare cancer, and so there is a small group of people who are really passionate about treating and understanding sarcomas. I will say ever since I've been involved in treating patients with sarcoma, that community continues to grow. And so I do think very slowly there is increased interest and dedication and awareness….

But a lot of that is also thanks to the patients and their caregivers, their friends, their families, working so hard to raise awareness. And there are a number of sarcoma foundations out there that are really working to provide support for patients. There are several of them, the Rein In Sarcoma Foundation, The Leiomyosarcoma Sarcoma Foundation, Sarcoma Foundation of America, et cetera. There are a number of Facebook groups that have been founded by patients or loved ones of patients who have passed away because of their sarcoma, that are really passionate about trying to do better for patients in the future. And I think that movement can be really powerful.

Amy Cohen Epstein: I absolutely agree. I agree. There's something very powerful about survivors talking.

Dr. Brittany Siontis: Yes.

Amy Cohen Epstein: For sure. And it's a little harder when you're talking about people who've lost someone…

Switching gears just a little bit: I love that you are at the top of your game. You're a female oncologist. Give us some of your backgrounds. How did you end up in this life? And did you always want to be a scientist, a researcher, a doctor? Because there's a whole difference between growing up a little girl and wanting to be a doctor, and then being an expert in a very small field and top of your game with the Mayo Clinic. And I think it's incredibly inspiring for lots of people to hear.

Dr. Brittany Siontis: It was not a straight path at all. It was a very circuitous path. I was definitely one of those kids who always grew up saying I was going to be a doctor. No one in my family is in the medical field, so I don't really know where that came from as a kid, but I always said this is what I was going to do with my life. And then when I was in high school, I actually attribute my interest in science to one of my high school biology teachers. She was phenomenal and really just kind of sparked that passion in science in me, and the curiosity that is really needed to be successful in science. And so all throughout my undergrad, I knew the end goal was to get into medical school. I went to University of Washington in Seattle, which was phenomenal experience.

And when I started medical school actually, I thought I was going to go into obstetrics and gynecology, so I obviously ended up in a very different place. And through my various rotations, I really developed a love for internal medicine. And looking back to my time as a little girl and thinking about that picture in my mind of what it was going to be like to be a doctor, it was really an internist. That's what I thought about. So I ended up going to internal medicine residency and I did that here at Mayo Clinic. And then thought I was going to go into pulmonary and critical care. So again, I said a very circuitous path. I really was very interested in lung physiology and the science behind that, and so was sort of on this path of pulmonary and critical care.

And it was during my second year of residency, over the Christmas holiday actually, that I was on our inpatient leukemia service, and just had one of the most profound patient experiences. One that I will remember forever. I spent two weeks in the hospital taking care of the most lovely gentleman and got to know him and his family. And it was through that experience that I realized that I was meant to go into the field of hematology-oncology, and so I completely switched gears. I ended up applying for hematology-oncology. And then through some very early experiences in my fellowship training, learned about this crazy cancer called sarcoma and just really fell in love with the complexity and the heterogeneity under this umbrella of one diagnosis. I love that I get to see patients of all ages. I love that I get to treat men and women. And every conversation with every patient every day is a little bit different, which keeps things challenging, but interesting at the same time.

Amy Cohen Epstein: That's amazing. I love that. And what's your support system like? Because I know you have a five-month-old, who's home napping right now.

Dr. Brittany Siontis: I do have a really wonderful support system. My husband is amazing and has always been incredibly supportive of me, of my career. We have been great partners as we've sort of entered this parenthood journey together. He is also a physician, so there are advantages that he understands what I do. He's not in oncology, but he is in medicine, so has sort of that understanding of the job aspects and what comes along with that.

And here at work, I'm very fortunate to have really amazing and incredible colleagues because things can be hard sometimes when we're dealing with this cancer. And sometimes it just feels like all I'm doing is giving bad news.

Amy Cohen Epstein: What would be sort of the one takeaway that you would say to people when now learning about sarcomas? When I talk to women, in particular, I tell them to know your baseline, know what your normal is. And you have to be in touch with your body mentally and physically and know when something is off and when something's wrong. And there's a fine line between being a hypochondriac and going crazy and running yourself rampant to every doctor under the sun. But that is a line, and so there is a lot of room up to that to be your own best advocate. When things really feel off, it's up to us to say something.

Dr. Brittany Siontis: I 100% agree with what you just said, and I actually tell my patients that all the time, whether it be at the time of their original diagnosis, or they've completed therapy and now they're under the surveillance and they sort of feel like they're waiting for this other shoe to drop. And what do they need to look out for? And I tell my patients all the time, "You know your body better than anybody else. And I want you to call me if you feel like something is changed, it's persistent, and you don't have something else to explain it away." We all get GI bugs. We all get aches or pains. We all get things here or there. But if you have a symptom or you have something that's going on that you know is not your normal, to use your words, and you can't explain it away because you were shoveling your driveway yesterday, or you went out and have been training for a marathon, et cetera, those are really the things that need to be brought to the attention of someone.

Amy Cohen Epstein: Yeah. It must be really challenging also because sarcoma, like you said, affects people of all ages, so you have to, in addition to educating the medical population and adults, also children and parents to children… Women, we're prone to just taking care of everybody else. So that's a huge challenge and I applaud you for talking about this and connecting with great foundations that are doing work in your field to get the educational part of it is so important.

Dr. Brittany Siontis:

Yeah. It is. And I think too, educating patients, caregivers, but also other providers because even within the field of oncology, they may go their entire career with never seeing a sarcoma. So through continued medical education, online resources, we're always looking as well to educate other providers too. Yes, it's rare, and most of the time it's not going to be sarcoma, but please keep it on your radar because if it is, we really want to capture those patients early and get them to providers who know this disease and treat it often.