Radiation Oncology in the Care of GI Malignancies

Transcript

00:00 --> 00:02Funding for Yale Cancer Answers is
00:02 --> 00:04provided by Smilow Cancer Hospital.
00:06 --> 00:08Welcome to Yale Cancer answers with
00:08 --> 00:10your host doctor in East JGP are
00:10 --> 00:12Yale Cancer answers features the
00:12 --> 00:14latest information on cancer care by
00:14 --> 00:16welcoming oncologists and specialists
00:16 --> 00:18who are on the forefront of the
00:18 --> 00:20battle to fight cancer this week.
00:20 --> 00:22It's a conversation about radiation
00:22 --> 00:24oncology and the care of GI malignancies.
00:24 --> 00:25With Doctor Kevin.
00:25 --> 00:27Do Doctor Do is an associate
00:27 --> 00:29professor of therapeutic radiology
00:29 --> 00:31at the Yale School of Medicine,
00:31 --> 00:33where Doctor Jaguar is a
00:33 --> 00:35professor of surgical oncology.
00:36 --> 00:38So Kevin, maybe we can start off by
00:38 --> 00:39you telling us a little bit about
00:39 --> 00:41yourself and what it is you do,
00:41 --> 00:45sure, so I'm a radiation oncologist.
00:45 --> 00:49And what I do is I treat cancer patients
00:49 --> 00:52with radiation and work very closely
00:52 --> 00:55together with chemotherapy doctors,
00:55 --> 00:58medical oncologists, surgeons to work
00:58 --> 01:02together to help to take care of patients.
01:02 --> 01:04And I understand that your focus is
01:04 --> 01:06in GI malignancies, is that right?
01:06 --> 01:07Yes, that's right.
01:07 --> 01:10So I treat GI malignancies as you
01:10 --> 01:12said and that really is treating
01:12 --> 01:15everything from the neck down
01:15 --> 01:17throughout the digestive system.
01:17 --> 01:19So that includes things like esophageal
01:19 --> 01:22cancer, stomach cancers, liver cancers,
01:22 --> 01:26and cancers of the of the colon,
01:26 --> 01:30****** and and it. It really is a
01:30 --> 01:32very fulfilling thing to treat.
01:32 --> 01:37There's a huge variety of.
01:37 --> 01:39Of of treatment approaches and
01:39 --> 01:42it's a great collaboration between
01:42 --> 01:44all the different fields to
01:44 --> 01:46give patients the best outcomes
01:47 --> 01:49so you know when we think about
01:49 --> 01:51different cancers and we think
01:51 --> 01:52about the different modalities
01:52 --> 01:55with which they can be treated.
01:55 --> 01:58You know some cancers are treated primarily
01:58 --> 02:02with one modality or two modalities,
02:02 --> 02:05some require all three modalities.
02:05 --> 02:06In terms of surgery,
02:06 --> 02:08systemic therapy, and radiation.
02:08 --> 02:11So you know, can you talk to us a little
02:11 --> 02:13bit more about the role that radiation
02:13 --> 02:15plays in the various GI malignancies?
02:15 --> 02:18Is it better suited to some than others?
02:18 --> 02:21And how do you decide whether
02:21 --> 02:22radiation therapy is in the
02:22 --> 02:25cards for a given patient or not?
02:26 --> 02:27So I think there's two
02:27 --> 02:29parts to that question.
02:29 --> 02:31One is, when do we use radiation
02:31 --> 02:33treatment for GI malignancies and
02:33 --> 02:36then the other question is, you know,
02:36 --> 02:39how do we make that decision in terms of?
02:39 --> 02:41You know when to use radiation and
02:41 --> 02:44how do we combine that with other
02:44 --> 02:46treatments so the the the the two.
02:46 --> 02:49The reason why we may use
02:49 --> 02:51radiation for GI malignancies,
02:51 --> 02:54I think of it as too broad
02:54 --> 02:55treatment paradigms.
02:55 --> 02:58One is in combination with other
02:58 --> 03:00treatments like surgery or chemotherapy.
03:00 --> 03:02And again we combine treatments
03:02 --> 03:04to give patients the best
03:04 --> 03:06functional and currative outcomes
03:06 --> 03:09for their cancers and then the.
03:09 --> 03:11Other approach is really
03:11 --> 03:13using radiation alone.
03:13 --> 03:17Either to come will give high doses
03:17 --> 03:21of radiation in what we call in a
03:21 --> 03:24blade of approach to control cancer
03:24 --> 03:27growth or for palliation in order
03:27 --> 03:31to help relieve symptoms of cancer,
03:31 --> 03:34such As for for patients.
03:34 --> 03:36And, you know,
03:36 --> 03:38I think the approaches that
03:38 --> 03:40we're using these days with.
03:40 --> 03:43Improved technologies for radiation
03:43 --> 03:48really has allowed us to be to to
03:48 --> 03:52really formulate and be able to
03:52 --> 03:54deliver a broad range of treatment
03:54 --> 03:57approaches using radiation treatment.
03:57 --> 04:00So it's not really A1 size fits
04:00 --> 04:01all treatment.
04:01 --> 04:05The in terms of when we may use radiation.
04:05 --> 04:06You know,
04:06 --> 04:08it really is a multidisciplinary approach.
04:08 --> 04:09In this team effort,
04:09 --> 04:10and that's really one of the.
04:10 --> 04:13Really phenomenal things that I
04:13 --> 04:16enjoy about treating gastrointestinal
04:16 --> 04:18cancers is that every patient
04:18 --> 04:20that we treat is really a a a,
04:20 --> 04:21a,
04:21 --> 04:23a collaboration and a group discussion
04:23 --> 04:25among really world experts.
04:25 --> 04:28Here in GI malignancies and figuring
04:28 --> 04:32out the best combination of treatment
04:32 --> 04:34approaches for each patient.
04:34 --> 04:35In general,
04:35 --> 04:37when we're talking about combining
04:37 --> 04:39radiation treatment with
04:39 --> 04:40chemotherapy surgery,
04:40 --> 04:44you know we're talking about
04:44 --> 04:47treating patients with where,
04:47 --> 04:48where,
04:48 --> 04:51maybe surgery alone isn't
04:51 --> 04:54enough to cure patients,
04:54 --> 04:58or in in cases where you know
04:58 --> 05:01we're helping with the chemotherapy
05:01 --> 05:04to improve the the response of.
05:04 --> 05:06Of of cancer.
05:06 --> 05:08So when we think about radiation
05:08 --> 05:09treatment in that context,
05:09 --> 05:12we think about using radiation
05:12 --> 05:14in combination with surgery and
05:14 --> 05:17chemotherapy in order to give
05:17 --> 05:19the best cure rates to reduce the
05:19 --> 05:22chances of the cancer coming back
05:22 --> 05:25or to preserve the function of
05:25 --> 05:28of quality of life in the organ
05:28 --> 05:30function of of patients,
05:31 --> 05:35and so expand a little bit upon that because.
05:35 --> 05:37You know when we think about the
05:37 --> 05:39digestive tract, you know we,
05:39 --> 05:43we think about it, kind of doing its job,
05:43 --> 05:45but it's a little bit different
05:45 --> 05:47than when we think about radiation
05:47 --> 05:49therapy preserving function.
05:49 --> 05:51So for example, on this show,
05:51 --> 05:54we've we've talked to a variety of
05:54 --> 05:56experts on on various cancers and,
05:56 --> 05:58for example, in head and neck cancer
05:58 --> 06:00will often use radiation therapy.
06:00 --> 06:03If we had a tumor that was
06:03 --> 06:06very close to vocal cords, or.
06:06 --> 06:07Particular anatomic structures
06:07 --> 06:12that we did not want to surgically
06:12 --> 06:15resect in the GI tract.
06:15 --> 06:18Does that play a role or is
06:18 --> 06:21it more that you're trying to?
06:21 --> 06:23Assist with surgery,
06:23 --> 06:26so if you don't get a clear margin
06:26 --> 06:28and there's a concern that you've
06:28 --> 06:30left some disease behind and you
06:30 --> 06:32can't take more that you'd use
06:32 --> 06:34radiation in that situation,
06:34 --> 06:35tell us a little bit more about
06:35 --> 06:37how you make those decisions.
06:38 --> 06:39Yes, so you know I,
06:39 --> 06:41I think that's a really great example
06:41 --> 06:43of the use of radiation in for head
06:43 --> 06:45and neck cancers that you bring up,
06:45 --> 06:51and you know, I think in GI cancers we have.
06:51 --> 06:53An analogous situation,
06:53 --> 06:56which I think frames in how I
06:56 --> 06:59think about the role of radiation
06:59 --> 07:01treatment in GI cancers and,
07:01 --> 07:06and you know, in in the 1970s.
07:06 --> 07:10The they they actually first used
07:10 --> 07:14chemotherapy and radiation to cure a
07:14 --> 07:17type of GI cancer called anal cancers.
07:17 --> 07:19So these are cancers that developed
07:19 --> 07:22in the in the anal canal and
07:22 --> 07:26before the 1970s the the treatment.
07:26 --> 07:28The curative treatment was actually
07:28 --> 07:31a surgery and because this was
07:31 --> 07:34in the anal canal with anal,
07:34 --> 07:38the muscles that control the the sphincter
07:38 --> 07:41function there and the continents.
07:41 --> 07:44The the surgery would would would
07:44 --> 07:46would really be something which
07:46 --> 07:48patients found a debilitating.
07:51 --> 07:54So you know no one really.
07:54 --> 07:57No, no one really wanted to have this
07:57 --> 07:59surgery and and even the surgeons
07:59 --> 08:01didn't like doing this surgery.
08:01 --> 08:04So what they did in the 1970s was they
08:04 --> 08:06actually started using chemotherapy
08:06 --> 08:10and radiation to to try to shrink
08:10 --> 08:12things down and to help the surgery.
08:12 --> 08:15As you're saying to try to spare
08:15 --> 08:17those muscles and improve sphincter
08:17 --> 08:19function in these patients and
08:19 --> 08:22improve continence in these patients,
08:22 --> 08:24what they found was that actually
08:24 --> 08:26the majority of patients responded
08:26 --> 08:28to chemotherapy and radiation.
08:28 --> 08:31And and actually the these anal cancers
08:31 --> 08:35were largely cured with chemotherapy and
08:35 --> 08:37radiation very similar to the situation
08:37 --> 08:40you bring up in head and neck cancers.
08:40 --> 08:41And really,
08:41 --> 08:44this became a huge paradigm shift
08:44 --> 08:46for gastrointestinal cancers where
08:46 --> 08:49there is this idea that potentially
08:49 --> 08:52there's this subset of patients that
08:52 --> 08:54where they may respond very well
08:54 --> 08:56to chemotherapy radiation,
08:56 --> 08:57and you may actually.
08:57 --> 09:00Do what's called an organ
09:00 --> 09:01preservation approach.
09:01 --> 09:05These days this approach is is actually
09:05 --> 09:09being expanded out to other sites you know,
09:09 --> 09:09not.
09:09 --> 09:12Maybe not with is as high a
09:12 --> 09:14cure rate as with anal cancer,
09:14 --> 09:17but certainly we're we're trying
09:17 --> 09:19to improve outcomes there and
09:19 --> 09:21trying to improve response rates
09:21 --> 09:23with chemotherapy radiation trying
09:23 --> 09:26to improve organ preservation
09:26 --> 09:28rates with chemotherapy radiation.
09:28 --> 09:29But yes,
09:29 --> 09:33I think that's certainly something
09:33 --> 09:37which the the curative potential
09:37 --> 09:40of combined chemotherapy radiation
09:40 --> 09:41instead of surgery,
09:41 --> 09:44or together with surgery is
09:44 --> 09:46certainly something that is a huge
09:46 --> 09:48area of interest in our field.
09:48 --> 09:49What you allude to, though,
09:49 --> 09:52is actually also a very important aspect,
09:52 --> 09:55which is that there certainly are a lot
09:55 --> 09:58of sites in the gastrointestinal tract which.
09:58 --> 10:01Are very amenable to
10:01 --> 10:04surgery and and it really.
10:04 --> 10:09If the surgeon can remove a tumor
10:09 --> 10:11without too much functional consequence,
10:11 --> 10:14you know that becomes the primary
10:14 --> 10:16treatment and then a chemotherapy
10:16 --> 10:19radiation are really used to help
10:19 --> 10:22help that surgery and to help
10:22 --> 10:24improve the the the cure rate,
10:24 --> 10:26reduce the chance that the
10:26 --> 10:27cancer comes back or.
10:27 --> 10:28You know,
10:28 --> 10:29alternatively.
10:29 --> 10:32Get try to get things to to a
10:32 --> 10:35shrink up to optimize and get
10:35 --> 10:37the best surgery possible
10:38 --> 10:40so you know it's interesting though
10:40 --> 10:43if chemo radiation works so well in
10:43 --> 10:45anal cancer such that surgery may
10:45 --> 10:48not even be really needed and you
10:48 --> 10:50can preserve sphincter function.
10:50 --> 10:53You know, one wonders whether that could
10:53 --> 10:55be the case for other malignancies.
10:55 --> 10:59Why is it that people need to have
10:59 --> 11:01surgery as the primary modality?
11:01 --> 11:03Talk to us a little bit more about,
11:03 --> 11:06you know what is the thinking that
11:06 --> 11:10goes into surgery being a primary
11:10 --> 11:12modality versus chemoradiation,
11:12 --> 11:15one would think that the latter would
11:15 --> 11:17be better tolerated potentially,
11:17 --> 11:19and certainly nobody wants to go under
11:19 --> 11:22the knife. It's a little bit scary.
11:22 --> 11:25But is there a difference in biology
11:25 --> 11:28or is it really a bulk of disease?
11:28 --> 11:29How?
11:29 --> 11:32How do you kind of think about whether
11:32 --> 11:34chemo radiation would work in other
11:34 --> 11:37parts of the GI tract just as well as
11:37 --> 11:39surgery like it does in the anal canal?
11:40 --> 11:41Yeah, that that's a
11:41 --> 11:43really excellent question.
11:43 --> 11:45And actually that's what we debate a lot
11:45 --> 11:47when we talk about that collaborative
11:47 --> 11:50discussion that we have between surgery,
11:50 --> 11:52chemotherapy and radiation.
11:52 --> 11:55On a, you know, a weekly or twice
11:55 --> 11:57weekly or three times weekly basis.
11:57 --> 12:00As we all meet together and
12:00 --> 12:02and discuss our patients.
12:02 --> 12:06It really is a discussion of what would be.
12:06 --> 12:09Kind of the best treatment modality
12:09 --> 12:11or combination of treatments to
12:11 --> 12:13give the patient the best cure
12:13 --> 12:16rates and best quality of life.
12:16 --> 12:19There are many instances where surgery
12:19 --> 12:22is the appropriate treatment and the
12:22 --> 12:24primary treatment in GI cancers and
12:24 --> 12:28you know the advantage of surgery you know,
12:28 --> 12:31is that if you can remove the tumor
12:31 --> 12:33and remove it with safely and with
12:33 --> 12:36good quality of life after surgery,
12:36 --> 12:39that's 100% chance that the
12:39 --> 12:43cancer is removed and and gone.
12:43 --> 12:47And that's a big advantage to surgery.
12:47 --> 12:49The chemotherapy and radiation,
12:49 --> 12:50you know,
12:50 --> 12:53as much as I said that in anal
12:53 --> 12:55cancers the cure rate is excellent.
12:55 --> 12:58It's it's still not 100% and it's
12:58 --> 13:01even lower in many other GI cancers
13:01 --> 13:04in terms of the chance of having
13:04 --> 13:07the cancer go away with chemotherapy
13:07 --> 13:10and radiation compared to surgery,
13:10 --> 13:13and so it's really, uh,
13:13 --> 13:15interesting.
13:15 --> 13:17And really critical issue,
13:17 --> 13:20which is that what is the biology
13:20 --> 13:22of the tumor?
13:22 --> 13:25How does the biology respond
13:25 --> 13:27to chemotherapy and radiation?
13:27 --> 13:30What are the mechanisms of resistance?
13:30 --> 13:33Why do some cancers like anal
13:33 --> 13:36cancers respond so well so as to
13:36 --> 13:38make surgery you know almost,
13:38 --> 13:41uh, almost a secondary treatment
13:41 --> 13:44for for that cancer you know?
13:44 --> 13:46Why does that respond so well?
13:46 --> 13:49Compared to other cancers of
13:49 --> 13:52the GI tract where we make it,
13:52 --> 13:54certainly a certain percentage
13:54 --> 13:55of patients cured,
13:55 --> 13:59but but nowhere near as as high a cure rate.
13:59 --> 14:01You know that's act area of active
14:01 --> 14:03research and something that is
14:03 --> 14:05really critical for my field.
14:05 --> 14:09In radiation this idea that some
14:09 --> 14:12cancers are more radioresistant to to,
14:12 --> 14:16to to radiation and chemotherapy treatments.
14:16 --> 14:18Than than others and trying to
14:18 --> 14:21get it the answer of why that
14:21 --> 14:24is is really a very important,
14:24 --> 14:25I think,
14:25 --> 14:28to trying to make sure that again we
14:28 --> 14:30we keep improving our treatments and
14:30 --> 14:32improving our cure rates and patients
14:33 --> 14:35great. Well, we're going to pick up
14:35 --> 14:36this discussion right after we take
14:36 --> 14:38a short break for a medical minute.
14:38 --> 14:40Please stay tuned to learn more about
14:40 --> 14:42radiation oncology and the care of GI
14:42 --> 14:44malignancies with my guest Doctor Kevin. Do
14:45 --> 14:47funding for Yale Cancer answers
14:47 --> 14:49comes from Smilow Cancer Hospital.
14:49 --> 14:51With an event focused on nutrition
14:51 --> 14:53for cancer survivorship presented
14:53 --> 14:54by the Smilow Cancer Care
14:54 --> 14:56Center in Trumbull, April 14th.
14:56 --> 14:59Register at Yale Cancer Center.
14:59 --> 15:02Org or email cancer answers at Yale.
15:04 --> 15:06Breast cancer is one of the most common
15:06 --> 15:08cancers in women in Connecticut alone,
15:08 --> 15:11approximately 3500 women will be
15:11 --> 15:13diagnosed with breast cancer this year,
15:13 --> 15:15but there is hope,
15:15 --> 15:16thanks to earlier detection,
15:16 --> 15:18noninvasive treatments and the development
15:18 --> 15:21of novel therapies to fight breast cancer.
15:21 --> 15:23Women should schedule a baseline
15:23 --> 15:25mammogram beginning at age 40 or
15:25 --> 15:27earlier if they have risk factors
15:27 --> 15:28associated with the disease.
15:28 --> 15:30With screening early detection
15:30 --> 15:32and a healthy lifestyle,
15:32 --> 15:34breast cancer can be defeated.
15:34 --> 15:36Clinical trials are currently
15:36 --> 15:38underway at federally designated
15:38 --> 15:40Comprehensive cancer centers such
15:40 --> 15:42as Yale Cancer Center and its Milo
15:42 --> 15:44Cancer Hospital to make innovative
15:44 --> 15:46new treatments available to patients.
15:46 --> 15:49Digital breast Tomo synthesis or 3D
15:49 --> 15:51mammography is also transforming breast
15:51 --> 15:54cancer screening by significantly
15:54 --> 15:55reducing unnecessary procedures
15:55 --> 15:58while picking up more cancers.
15:58 --> 16:01More information is available at
16:01 --> 16:02yalecancercenter.org you're listening
16:02 --> 16:04to Connecticut Public Radio.
16:05 --> 16:07Welcome back to Yale Cancer answers.
16:07 --> 16:09This is doctor in East check part and I'm
16:09 --> 16:11joined tonight by my guest Doctor Kevin.
16:11 --> 16:13Do we're learning about radiation oncology
16:13 --> 16:17in the care of GI Malignancies and Kevin
16:17 --> 16:19before the break you left off with some
16:19 --> 16:21really interesting and important questions.
16:21 --> 16:23Which were, you know,
16:23 --> 16:26why is it that some cancers like
16:26 --> 16:29those in the anal canal, for example,
16:29 --> 16:31seem to be pretty radiosensitive
16:31 --> 16:35and can be treated very well with
16:35 --> 16:37chemotherapy and radiation Juarez?
16:37 --> 16:37Other cancers,
16:37 --> 16:41perhaps in other parts of the GI tract,
16:41 --> 16:45are not so well treated with chemo
16:45 --> 16:49radiation alone, and for those cancers,
16:49 --> 16:53surgery really is a primary modality.
16:53 --> 16:55Any idea as to why the biology
16:55 --> 16:58is different when we think about
16:58 --> 16:59the GI tract embryologically?
16:59 --> 17:03It all comes from essentially 1 hollow tube,
17:03 --> 17:03right?
17:04 --> 17:06Yes, absolutely yeah.
17:06 --> 17:08So anatomically and embryologically,
17:08 --> 17:10that's absolutely correct.
17:10 --> 17:12And this is really interesting.
17:13 --> 17:16Then why are some cancers what we
17:16 --> 17:18call Radioresistant and other cancers?
17:18 --> 17:20Radiosensitive, you know,
17:20 --> 17:22going back to your discussion
17:22 --> 17:25of the head and neck cancers.
17:25 --> 17:28You know, head and neck cancers
17:28 --> 17:30are are very radiosensitive,
17:30 --> 17:33especially when they are HPV positive.
17:33 --> 17:35This is a virus that many people
17:35 --> 17:38in the United States have at
17:38 --> 17:40some point in their life and it
17:40 --> 17:43predisposes cancer formation.
17:43 --> 17:44And you know,
17:44 --> 17:47it's an interesting thing where even
17:47 --> 17:49though it predisposes cancer formation
17:49 --> 17:52in the head and neck and actually
17:52 --> 17:56also in the anal canal that it actually.
17:56 --> 18:00Is a characteristic that makes these
18:00 --> 18:03cancers more sensitive to radiation?
18:03 --> 18:05It's kind of interesting to think
18:05 --> 18:09about why you know a virus which
18:09 --> 18:11may predispose formation of cancer
18:11 --> 18:14may also make the cancer more
18:14 --> 18:17sensitive to radiation and and one
18:17 --> 18:18thing to think about is potentially,
18:18 --> 18:19you know,
18:19 --> 18:21even though this virus is maybe
18:21 --> 18:23doing something it shouldn't in the
18:23 --> 18:26body that it also kind of sets up.
18:26 --> 18:28And I'm, you know,
18:28 --> 18:31logic environment where the the
18:31 --> 18:34radiation actually has a different
18:34 --> 18:38effect and different immune tumor
18:38 --> 18:41microenvironments that is that the
18:41 --> 18:45immune state the make up of you know,
18:45 --> 18:48immune cells that are in a tumor,
18:48 --> 18:51or that how your immune system reacts
18:51 --> 18:54to the tumor may actually impact
18:54 --> 18:58radio sensitivity or the response.
18:58 --> 19:01The radiation and and this has been
19:01 --> 19:03really studied quite a bit in recent years,
19:03 --> 19:06in with the explosion of immuno
19:06 --> 19:09therapies and and that that have
19:09 --> 19:10really been revolutionized.
19:10 --> 19:13Cancer care in the past few years.
19:13 --> 19:16The going to going to something a
19:16 --> 19:19tumor which is very radioresistant
19:19 --> 19:21pancreas tumors for example.
19:21 --> 19:25We do think that the that that surgery
19:25 --> 19:28is critically important in the cure.
19:28 --> 19:31With pancreas cancers and really
19:31 --> 19:34one of the only ways to to address
19:34 --> 19:38and and get rid of pancreas cancer.
19:38 --> 19:41And you know if you look at the
19:41 --> 19:42pancreas cancer tumor microenvironment
19:42 --> 19:46as as as we have in in our research,
19:46 --> 19:50it actually is is kind of an an
19:50 --> 19:52immunosuppressive environment or
19:52 --> 19:53an immune desert.
19:53 --> 19:56And in fact if you actually use
19:56 --> 19:58any of the immunotherapy's too.
19:58 --> 20:02To try to change up the tumor
20:02 --> 20:04microenvironment and change the
20:04 --> 20:07immune cell makeup of pancreas tumors,
20:07 --> 20:08you can actually, in some cases,
20:08 --> 20:11get a better response with radiation
20:11 --> 20:14treatment and and and we've actually
20:14 --> 20:17done some clinical trials looking at this,
20:17 --> 20:19which are ongoing at the moment,
20:20 --> 20:21and it's really interesting,
20:21 --> 20:23and so in terms of anal cancers.
20:23 --> 20:26Have you noticed a difference in
20:26 --> 20:28in the radio sensitivity of tumors?
20:28 --> 20:32Based on whether they are HPV related or not,
20:32 --> 20:36yes, so actually as you as
20:36 --> 20:38you're correctly saying,
20:38 --> 20:41that HPV negative tumors, that is,
20:41 --> 20:44tumors that are not associated with
20:44 --> 20:47HPV are actually more radioresistant
20:47 --> 20:49than HPV positive tumors,
20:49 --> 20:52and that's actually an interesting finding.
20:52 --> 20:55Even though we still use chemotherapy
20:55 --> 20:59and radiation and are able to cure.
20:59 --> 21:02In many cases, anal cancer,
21:02 --> 21:05regardless of whether or not HPV has
21:05 --> 21:08been involved in their formation, that is,
21:08 --> 21:12if they're HIV positive or HIV negative.
21:12 --> 21:13In fact, you know,
21:13 --> 21:15we think that HPP positive anal
21:15 --> 21:18cancers are are are so sensitive to
21:18 --> 21:21radiation that for early stage HPV
21:21 --> 21:23positive cancers we are even looking
21:23 --> 21:26at potentially a dose deescalating and
21:26 --> 21:29and reducing the dose of radiation.
21:29 --> 21:31In order to try to reduce radiation
21:31 --> 21:33exposure and reduce some of the
21:33 --> 21:35side effects associated with
21:35 --> 21:36chemotherapy radiation treatment.
21:36 --> 21:39Now the other point that you made before
21:39 --> 21:42the break was that for some cancers
21:42 --> 21:45where surgery plays a primary role,
21:45 --> 21:48it it really can remove the cancer.
21:48 --> 21:49But just to clarify,
21:49 --> 21:51one of the the things that you said,
21:51 --> 21:53which was that really can kind
21:53 --> 21:56of get rid of the cancer.
21:56 --> 21:58And yet we know that some
21:58 --> 22:00of these cancers come back.
22:00 --> 22:03So can you talk about the role of radiation?
22:03 --> 22:06Kind of as a belt and suspenders
22:06 --> 22:08approach to these cancers in preventing
22:08 --> 22:10some of them from coming back?
22:11 --> 22:13Absolutely yeah, so that's actually
22:13 --> 22:15another really good example of how we
22:15 --> 22:17use radiation treatment and a classic
22:17 --> 22:20example of that is if we go, you know,
22:20 --> 22:23a little bit higher up in the GI tract
22:23 --> 22:26into the ****** which is the part
22:26 --> 22:30of the colon that is in the pelvis.
22:30 --> 22:34And you know where we use radiation to
22:34 --> 22:38support surgery is is is in rectal cancers.
22:38 --> 22:40And you know biologically,
22:40 --> 22:43you know as as you were saying earlier,
22:43 --> 22:45you know the the the colon is actually
22:45 --> 22:47biologically the same as the ******.
22:47 --> 22:49It's all part of the large bowel you know.
22:49 --> 22:53Part of the gut and the difference
22:53 --> 22:56between colon cancers which are above
22:56 --> 22:59the pelvis and then rectal cancers,
22:59 --> 23:01which is part of the colon that's
23:01 --> 23:02in the pelvis.
23:02 --> 23:05Is is that in the in the colon,
23:05 --> 23:07which is outside of the Bony pelvis?
23:07 --> 23:08You know,
23:08 --> 23:12there's a lot of room and a lot of space
23:12 --> 23:15for surgeons to remove the the cancer,
23:15 --> 23:18and they're really able to take out
23:18 --> 23:21colon cancers with clear margins.
23:21 --> 23:23You know lots of space in between
23:23 --> 23:25the tumor and normal tissue,
23:25 --> 23:28and in for colon cancers.
23:28 --> 23:29We actually very rarely,
23:29 --> 23:32if ever, use radiation treatment.
23:32 --> 23:35Because surgeons are able to get
23:35 --> 23:38such wide clearance with surgery.
23:38 --> 23:38However,
23:38 --> 23:41in the pelvis the the pelvis is more limited.
23:41 --> 23:44It's a smaller space and the margins
23:44 --> 23:47or the clearance that the surgeons
23:47 --> 23:50can get with their surgery is also
23:50 --> 23:53less and and so there is a higher
23:53 --> 23:55chance despite colon cancers being
23:55 --> 23:57very similar biologically to rectal
23:57 --> 23:59cancers because of the space issues,
23:59 --> 24:01there's a higher chance that
24:01 --> 24:03the cancer can come back.
24:03 --> 24:05When it's in the ****** in the
24:05 --> 24:07pelvis and and we routinely
24:07 --> 24:09would use radiation to clean up.
24:09 --> 24:12After these smaller margins in and reduce
24:12 --> 24:14the chance of the cancer coming back.
24:14 --> 24:17So that's an example of how we use radiation.
24:17 --> 24:19As you said to to help support surgery.
24:19 --> 24:22Now before the break you had also
24:22 --> 24:24mentioned that there are a variety of
24:24 --> 24:27other reasons why we use radiation in the
24:27 --> 24:29care of patients with GI malignancies,
24:29 --> 24:31and one of the things that
24:31 --> 24:33you mentioned was ablation.
24:33 --> 24:35So can you talk to us a little bit
24:35 --> 24:38about what exactly is ablation and
24:38 --> 24:40how and where do you use it? Yeah,
24:40 --> 24:44so ablation ablation when I said ablation,
24:44 --> 24:47I was referring to a type of
24:47 --> 24:48radiation treatment called
24:48 --> 24:51stereotactic radiation treatment,
24:51 --> 24:54and this is actually a technique
24:54 --> 24:56of radiation where we give
24:56 --> 24:58high doses of radiation very,
24:58 --> 25:03very precisely to tumors and so.
25:03 --> 25:04It's something which has
25:04 --> 25:07only recently in the past.
25:07 --> 25:10I would say 20 years or so been
25:10 --> 25:14really well developed for our for
25:14 --> 25:17radiation treatments with the with
25:17 --> 25:21the really huge advancements in
25:21 --> 25:23radiology diagnostic radiology.
25:23 --> 25:27Really having good CT scan or
25:27 --> 25:31MRI scan imaging to really very
25:31 --> 25:33clearly define tumors.
25:33 --> 25:34In a very precise way,
25:34 --> 25:37and we use these images together
25:37 --> 25:40with with some very complex
25:40 --> 25:43treatment planning approaches
25:43 --> 25:48to aim very carefully at tumors.
25:48 --> 25:49So with these techniques,
25:49 --> 25:52and with this precision treatment we
25:52 --> 25:54can actually give much higher doses
25:54 --> 25:57of radiation treatment to tumors
25:57 --> 25:59while making sure that we keep the
25:59 --> 26:02surrounding normal tissue to safe doses.
26:02 --> 26:06Where this is developed is that we now
26:06 --> 26:09think and that we can actually give
26:09 --> 26:12high doses of radiation and get very
26:12 --> 26:16good control of the growth of tumors.
26:16 --> 26:19What we call ablation in some cases,
26:19 --> 26:22in some locations you know.
26:22 --> 26:25Again, we think that the outcomes
26:25 --> 26:28can be similar to surgery.
26:28 --> 26:32You know this is something where, again,
26:32 --> 26:34you know surgery probably still has.
26:34 --> 26:36The advantage in that if something
26:36 --> 26:38can be safely taken out send
26:38 --> 26:40it makes sense to take it out.
26:40 --> 26:42That probably it should be taken out,
26:42 --> 26:45but if there is any discussion
26:45 --> 26:49about how you know the patient may
26:49 --> 26:51handle having surgery or whether
26:51 --> 26:54or not it may not be in the right
26:54 --> 26:57position at the proper place in the
26:57 --> 27:00body to to remove it surgically.
27:00 --> 27:03That this stereotactic ablation
27:03 --> 27:05technique with radiation treatment.
27:05 --> 27:08Can be a good substitute for surgery.
27:08 --> 27:12The indications for using it are one
27:12 --> 27:16potentially to ablate early stage disease.
27:16 --> 27:17You know,
27:17 --> 27:18we are starting to use this.
27:18 --> 27:20I mentioned pancreas cancer,
27:20 --> 27:22you know we're starting to use this
27:22 --> 27:24more and more in pancreas cancer,
27:24 --> 27:27where we think because pancreas
27:27 --> 27:31cancer is a radio resistant type
27:31 --> 27:34of cancer that higher doses of
27:34 --> 27:36radiation actually can get.
27:36 --> 27:38Good control of the cancer.
27:38 --> 27:40Even though we we don't think
27:40 --> 27:42of it as as good as surgery,
27:42 --> 27:43yet you know,
27:43 --> 27:46I I mentioned that we are doing
27:46 --> 27:49some clinical trials to see how we
27:49 --> 27:51can improve radiation treatment,
27:51 --> 27:53potentially with the combination of
27:53 --> 27:57immunotherapy's and then in addition,
27:57 --> 28:00the other indication for stereotactic
28:00 --> 28:03ablative treatment may be potentially
28:03 --> 28:05in in patients where.
28:05 --> 28:06For example,
28:06 --> 28:09maybe the cancer has spread and
28:09 --> 28:11they're on systemic therapies,
28:11 --> 28:14and they may have just a spot or of
28:14 --> 28:17cancer that's escaped from the chemotherapy.
28:17 --> 28:20It's developed changes where they
28:20 --> 28:22may actually be growing through
28:22 --> 28:24the chemotherapy treatment,
28:24 --> 28:27and we can actually use stereotactic
28:27 --> 28:30a blade of radiation to get those
28:30 --> 28:32spots under control for patients.
28:33 --> 28:35Doctor Kevin do is an associate
28:35 --> 28:36professor of therapeutic radiology
28:37 --> 28:38at the Yale School of Medicine.
28:38 --> 28:40If you have questions,
28:40 --> 28:42the address is canceranswers@yale.edu
28:42 --> 28:45and past editions of the program
28:45 --> 28:47are available in audio and written
28:47 --> 28:49form at Yale Cancer Center Org.
28:49 --> 28:51We hope you'll join us next week to
28:51 --> 28:53learn more about the fight against
28:53 --> 28:55cancer here on Connecticut Public radio
28:55 --> 28:57funding for Yale Cancer Answers is
28:57 --> 29:00provided by Smilow Cancer Hospital.

Information

Radiation Oncology in the Care of GI Malignancies with guest Dr. Kevin Du April 3, 2022 Yale Cancer Center visit: http://www.yalecancercenter.org email: canceranswers@yale.edu call: 203-785-4095