MD Anderson Cancer Center
Lisa Garvin: Welcome to Cancer Newsline, a podcast series from the University of Texas MD Anderson Cancer Center. Cancer Newsline helps you stay current with the news on cancer research, diagnosis, treatment and prevention, providing the latest information on reducing your family's cancer risk. I'm your host Lisa Garvin, and today our guest is Dr. Cathy Eng. She is an associate professor of GI Medical Oncology and also associate director of our colorectal center here at MD Anderson and we're going to be talking about a pretty rare form of cancer, appendix cancer. So Dr. Eng, appendix cancer as a whole is pretty darn rare, isn't it?
Dr. Cathy Eng: It's extremely rare. And I'd like to thank you for having me on this podcast. Impacts basically anywhere from reportedly 600 to 1,500 individuals per year, so it's an extremely rare cancer and it's often found incidentally.
Lisa Garvin: What sort of spectrum do you see as far as people who are diagnosed, as far as age, gender, ethnicity?
Dr. Cathy Eng: I would say that's a hard--it's a bit hard to describe because in fact, it's so rare that there hasn't been a lot of work generated regarding the age groups, the ethnicities. I would say, from our perspective at least from our patient population probably the median ages anywhere between 50 and 60 and it tends to be a Caucasian patient population granted that's also a large patient population that we see at this institution. But at least, regarding the age from what I've looked at in regards to other small amount of literature that's been completely in the past, it appears to be roughly the same age group.
Lisa Garvin: Now when people--you say that misdiagnosis is fairly common with appendix cancer.
Dr. Cathy Eng: Well--
Lisa Garvin: Not misdiagnosis maybe, but maybe people think that it's something else.
Dr. Cathy Eng: Correct. It's commonly diagnosed at the time of patient's believing that they may or may not have early signs of appendicitis. It's commonly found incidentally when the surgeon is going in there for the appendectomy.
Lisa Garvin: What is the prognosis generally of these patients?
Dr. Cathy Eng: If it's caught early on and has not spread or metastasized and it just remains in the local organ and maybe with the associate lymph nodes, the prognosis is very good. The patient is then usually referred for a right-sided what we call hemicolectomy, where part of the colon is also removed that was adjacent to the appendix, as well as the associate lymph nodes to make sure that there was an adequate surgical resection. And those patients do extremely well and have a very good five years survival. It's those patients though that present with disease outside of the original organ, those are the ones that we are most concerned about because that means that their tumor has often metastasized. And this tumor is unique because it metastasizes basically within the peritoneum which is basically the abdominal cavity, not necessarily within an organ but within the abdominal cavity itself.
Lisa Garvin: I know there's a certain subtype pseudomyxoma peritonei--
Dr. Cathy Eng: Correct.
Lisa Garvin: I guess where there are microscopic tumors just all over the inside of the peritoneum.
Dr. Cathy Eng: Well, that's actually how all appendiceal cancers when they metastasize do spread, but pseudomyxoma peritonei is also very unique because it's a very--involves a very gelatinous material and it can be very bulky in appearance also. So on a CAT scan, it can be very difficult to visualize exactly what the borders of the tumor are and if there's a large amount of tumor burden meaning that there's a large amount of disease within the patient's abdominal cavity, it can cause a lot of discomfort, basically abdominal pain, they feel a lot of fullness and bloating, and actually they lose their appetite 'cause their abdomen is so full.
Lisa Garvin: So typically, the treatment for appendix cancers starts with surgery?
Dr. Cathy Eng: So for early stage disease, surgery is the standard of care but for more advanced disease, meaning where it's spread to the abdominal cavity or peritoneum, there's different grades of appendiceal cancers. And so just in general, there are two categories, a well-differentiated which is more of a low grade tumor and the moderate to poorly-differentiated which is considered a more high grade tumor. Most well-differentiated appendiceal tumors in fact are very slow growing and so it allows the surgeon to basically take advantage of the fact that he can do--as long as there's no evidence of disease, mind you, to the other organs, it allows them to go ahead and do a surgical resection of all the sites of disease that they can see and proceed to do a procedure called HIPEC or Heated Intraperitoneal Chemotherapy. That's pretty much the standard of care for appendiceal carcinomas and then unfortunately, there are those patients that are either have a lot of tumor burden or that recently have the HIPEC and have had recurrence early on, or patients with a very--the more aggressive tumor type in which our surgeons don't necessarily want to take them immediately for the cytoreductive surgery and the HIPEC because they're very high risk for recurrence.
Lisa Garvin: So you said we wanted to focus on people who are not surgical candidates for this disease, what sorts of alternatives are there?
Dr. Cathy Eng: So for patients with a more high grade appendiceal carcinomas, our tendency at this institution is to often consider them for chemotherapy upfront in the hopes of trying to ensure stability of disease and of course ideally, it'd be nice to shrink some of the tumor but really did demonstrate that the disease can be stabilized and controlled roughly for a period of anywhere for three to six months depending upon our surgeons' preference. And then they may consider taking that patient to cytoreductive surgery and HIPEC if appropriate. And then there are those patients that are never good candidates for surgery 'cause they have other medical problems or because they have so much tumor burden or anatomically where their tumor appears on their CT scan, the surgeon realizes that he could not have the patient undergo adequate resection. Those patients as long as they have good energy level, as long as their laboratory tests are normal; those patients are those that we commonly consider chemotherapy for.
Lisa Garvin: So Dr. Eng, I understand that there are a couple of exciting clinical trial opportunities for appendiceal cancer.
Dr. Cathy Eng: Yes, actually there is one study that we just opened recently, specifically for well-differentiated mucinous appendiceal carcinoma patients that are not surgical candidates, it's for treatment naive patients and it's a small study comparing the role of observation upfront for six months versus chemotherapy for six months and then the patients go in the opposite arm. Basically seeing how they benefit from treatment for well-differentiated tumors.
Lisa Garvin: And how many patients are you hoping to enroll?
Dr. Cathy Eng: That trial is a smaller study. The goal is to hopefully obtain at least 24 patients in total for both arms combined.
Lisa Garvin: And I understand there's another clinical trial that's also going to be launching in the coming weeks.
Dr. Cathy Eng: We hope. It's not going to be in the next coming weeks, possibly in the next couple of months. It's a study specifically for moderate to poorly-differentiated adenocarcinoma of the appendix also in treatment of naive patients that are not surgical candidates. And we hope to get it opened by the beginning of the year.
Lisa Garvin: Given the rise or increase of targeted and molecular therapies, are there any avenues that are being explored for appendix cancer?
Dr. Cathy Eng: And that's great question actually. So currently, the standard of care roughly is to provide patients similar chemotherapy that we use in colon cancer. First of all, we actually don't know if that's the best treatment to apply to this patient population but because it's adjacent anatomically, it appears to make sense and so a lot of the treatments that we have utilized are commonly provided in colorectal cancer, in metastatic disease. We have been utilizing those treatments and in addition, we have been using some of these so-called targeted therapies. What's unique about appendiceal cancer because it's so rare, there's not a lot of literature regarding predictive and prognostic markers in tissue analysis and because we have three very dedicated surgeons here, we actually now have a protocol that we recently just got approved specifically to analyze the specimens of our patients to look at molecular marker analysis, to see if we can identify anything that would give us any hint of those patients that would be optimal candidates for surgery, those patients that are optimal candidates for a certain type of chemotherapy, what's a poor prognostic indicator that may prohibit them--I'm sorry, prohibit us from considering them for surgery, et cetera. So we've actually done a little bit of work looking at our patients that have been treated in the past and we looked at the type of chemotherapy they received and what we've actually presented at ASCO, our national oncology meeting in 2012 was that we know that that combination chemotherapy appear to fair best for these patients. And in addition, we also noted that the use of bevacizumab, which is an antiangiogenic agent approved in metastatic colorectal cancer, it appear to improve the overall survival of our patients when we utilized it. So actually our next goal is to validate the data that we've generated and we've applied for a protocol with unspecified pharmaceutical company at this time, to see if we can actually validate this data and move it forward to probably one of the first trials specifically for this patient population.
Lisa Garvin: It must be extremely frustrating when you're dealing with a very rare cancer 'cause you have a paucity of data and, you know, something to hook a research protocol on to. When you were saying like about a thousand people, is that just in the United States or is that worldwide?
Dr. Cathy Eng: From my understanding 'cause I've looked at this specifically and I actually tried to look at the worldwide incidence, I really couldn't find any specific numbers worldwide. One, there were some literature that said potentially 1,500 total so it's really not much different from what's been reported in the US. But I did want to basically elaborate when you said, it is a very frustrating to treat this malignancy because there is a lack of literature and in part because it's such a rare cancer, there's not a lot of pharmaceutical support. However, because we have some very dedicated--we basically have a very dedicated team at this institution. We run a basically bimonthly and every two weeks conference on--with--that's a multidisciplinary conference specifically focusing on our appendiceal patient population which involves our pathologists, radiologists, medical oncologists, and surgical oncologists. And we discuss every case basically to determine whether or not that patient is an optimal surgical candidate versus a candidate for chemotherapy. And in addition, we've actually had a family that was a patient here that there loved one passed, and they've created now a fundraiser called Shoot for the Cure, which specifically helps us with raising research funds basically to focus on tissue analysis and blood collection analysis to try to get more information to help others that need this information because there are so little information out there.
Lisa Garvin: So you've been able to reach out to your colleagues both, you know, nationally and internationally?
Dr. Cathy Eng: That's what we're trying. We're definitely moving forward with that. I would say we've made some great strides and we've definitely had some--basically some very nice oral presentations and poster presentations regarding some of the work that we've done here and we continue to expand upon it.
Lisa Garvin: And typically, rare cancers tend to end up at a place like MD Anderson, I believe out of the thousands cases, we treat a fair amount of those here.
Dr. Cathy Eng: I believe so, and in part because we are a large referral center as you noted and very few places I think have a dedicated group of individuals focused on a cancer that impacts less than a thousand individuals per year.
Lisa Garvin: Is there anything you'd like to wrap up with, any final thoughts on where we're going with appendiceal cancer treatment?
Dr. Cathy Eng: I would say that, you know, there definitely is a lot to be learned still and we're definitely working on expanding upon that further. And there are individuals that need this information and so that's why we continue to update our literature and our education and we are very appreciative of individuals such as the Ric Summers Foundation that sponsors the Shoot for the Cure 'cause they're helping to get the word out. And that brings individuals back to MD Anderson so they could see what we have to offer here and basically allows us to continue to evaluate these patients further. Because the standard of care for some patients, as we mentioned earlier, is cytoreductive surgery and HIPEC but unfortunately, there's also those individuals that are not candidates for surgery at all and those are the ones that we really need to learn about on how to move the field ahead with those individuals rather than just treating them just like a standard colorectal patient because it's clearly not the case. They are very different entity, a very different type of cancer.
Lisa Garvin: Thank you for being with us today.
Dr. Cathy Eng: Thank you so much.
Lisa Garvin: If you have questions about anything you've heard today on Cancer Newsline, contact Ask MD Anderson at 1-877-MDA-6789 or online at mdanderson.org/ask. Thank you for listening to this episode of Cancer Newsline. Tune in for the next podcast in our series.
© 2013 The University of Texas MD Anderson Cancer Center
1515 Holcombe Blvd, Houston, TX 77030
1-800-392-1611 (USA) 1-713-792-6161