EBT vs traditional HDR for skin cancer

[probiotic]

Hi guys
Personally i dont have any experience with EBT for skin cases but i have done lots of HDR molds with a cobalt source. is there any dosimetric advantage for EBT over conventional hdr?


Sent from my iPhone using Tapatalk

---

Members don't see this ad.

 

[medgator]

I only do electrons. No idea. I'm curious about reimbursement and preference for one over the other though, obviously hdr has stricter requirements for physical presence...

 

[thecarbonionangle]

We mostly do skin collimation with electrons, custom-made lead mask. External beam would be for rare cases.

 

[medgator]

We mostly do skin collimation with electrons, custom-made lead mask. External beam would be for rare cases.

I think the op meant ebt = electron beam therapy. I would think electrons would fall under "external beam" though

 

[probiotic]

I apologize for the confusion but
I'm asking about electronic brachytherapy


Sent from my iPhone using Tapatalk

 

[seper]

good question. I do contact HDR using Ir-192 and was wondering if anyone looked hard into surface dosimetry of Ir-192 vs. EBT

 

[Reaganite]

Depends on what type of brachytherapy you are talking about. If you are talking about surface stuff with iridium or a kv source, advantage of EBRT is deeper penetration with lower surface dose. EBRT is also probably a little more forgiving of tumor delineation errors since you get a wider penumbra. I treat a ton of skin cancer, and it can be tough to accurately delineate the borders of some of these cancers, particularly the squams. I know some derms who do "tumor border biopsies" for this very reason. I think most of us feel comfortable with more generous tumor delineation when we're treating at standard EBRT fractionation of 2-3 Gy per day. With a surface applicator prescribing 5 Gy to depth, you may be getting 10 Gy on the surface. You're probably going to be a little less generous in you tumor delineation. I mostly do brachy for basals since they are usually well defined, but prefer EBRT for squams because I've personally seen (and have heard this from several others) marginal misses with brachy.

 

[Pewl]

Depends on what type of brachytherapy you are talking about. If you are talking about surface stuff with iridium or a kv source, advantage of EBRT is deeper penetration with lower surface dose. EBRT is also probably a little more forgiving of tumor delineation errors since you get a wider penumbra. I treat a ton of skin cancer, and it can be tough to accurately delineate the borders of some of these cancers, particularly the squams. I know some derms who do "tumor border biopsies" for this very reason. I think most of us feel comfortable with more generous tumor delineation when we're treating at standard EBRT fractionation of 2-3 Gy per day. With a surface applicator prescribing 5 Gy to depth, you may be getting 10 Gy on the surface. You're probably going to be a little less generous in you tumor delineation. I mostly do brachy for basals since they are usually well defined, but prefer EBRT for squams because I've personally seen (and have heard this from several others) marginal misses with brachy.

I do a ton of skin as well. I use Leipzigs only if it's a small, superficial, and WELL defined lesion. The dose dropoff is pretty steep and cosmesis is excellent but when in doubt I just stick to electrons. The derms usually cut on the "easy" cases and I always end up with the weird nostril or vermillion lip skin lesions.

 

[medgator]

I do a ton of skin as well. I use Leipzigs only if it's a small, superficial, and WELL defined lesion. The dose dropoff is pretty steep and cosmesis is excellent but when in doubt I just stick to electrons. The derms usually cut on the "easy" cases and I always end up with the weird nostril or vermillion lip skin lesions.

Yeah but I usually get their post op referrals and/or recurrences after the 2nd or even 3rd mohs lol, esp stuff on the nose where they weren't able to clear it well enough

 

[MOHS_01]

I do a ton of skin as well. I use Leipzigs only if it's a small, superficial, and WELL defined lesion. The dose dropoff is pretty steep and cosmesis is excellent but when in doubt I just stick to electrons. The derms usually cut on the "easy" cases and I always end up with the weird nostril or vermillion lip skin lesions.

Then they are not doing their job well. Sorry for that, I've seen more and more of it as the years go by.

Yeah but I usually get their post op referrals and/or recurrences after the 2nd or even 3rd mohs lol, esp stuff on the nose where they weren't able to clear it well enough

Why are they not clearing it well? Poor histotechs? They cannot interpret their slides? They don't know when immunostains are indicated? Just plain lazy? Bone involvement? My guess is some combination of the first several factors combined with the desire to avoid anything difficult, punt it to someone else. It's always easier to call a doctor than to be one. SMH

 

[medgator]

Why are they not clearing it well? Poor histotechs? They cannot interpret their slides? They don't know when immunostains are indicated? Just plain lazy? Bone involvement? My guess is some combination of the first several factors combined with the desire to avoid anything difficult, punt it to someone else. It's always easier to call a doctor than to be one. SMH

Some of the cases are flat out recurrences. In other situations, I've gotten + margin cases after mohs for nasal bridge or ala lesions which are difficult imo surgically and probably should go to xrt anyways

 

[MOHS_01]

Some of the cases are flat out recurrences. In other situations, I've gotten + margin cases after mohs for nasal bridge or ala lesions which are difficult imo surgically and probably should go to xrt anyways

Interesting; I've always been intrigued by the philosophical differences centering on what is proper between disciplines. Out of curiosity -- because I have zero interest or intent to come into your yard an **** all over it and know up front that we likely have differing opinions -- what would you believe should go to XRT anyways? Honest question.

 

[medgator]

Interesting; I've always been intrigued by the philosophical differences centering on what is proper between disciplines. Out of curiosity -- because I have zero interest or intent to come into your yard an **** all over it and know up front that we likely have differing opinions -- what would you believe should go to XRT anyways? Honest question.

I'm being very objective here... nasal lesions are difficult in many cases if you are trying to preserve the organ/cosmesis. Could apply to some ear lesions as well.

Oral commisure lesions. Surgery carries a higher risk of oral incontinence.

 

[MOHS_01]

I'm being very objective here... nasal lesions are difficult in many cases if you are trying to preserve the organ/cosmesis. Could apply to some ear lesions as well.

Oral commisure lesions. Surgery carries a higher risk of oral incontinence.

Pardon my ignorance here but I've often wondered: given that any CA is a space occupying lesion... and if treatment is to be successful, the entire lesion has to be killed, what happens with healing? I know the three dimensional aspects of these tumors as I am stuck chasing them down daily... and I know that if treatment is to be successful, tumor has to leave, adnexal structures take the friendly fire and are diminished, and atrophy of the dermis is appreciated... the histologic effects of radiation are well recognized... how (physically) is it that cosmesis (or even function, depending on the area treated) is retained if the mass effect of the tumor is anything other than minimal? I've never been given an answer to this question -- and am genuinely curious. Everywhere I have trained or practice has always treated XRT as the red headed step child -- second line, reserve therapy for primary tumors with aggressive features or complicating patient psychology, intraneural or intravascular involvement, recurrent with field effect, high metastatic risk, etc., so I have had precious little good exposure to it. Community docs have burned people up, creating one helluva mess when they have secondary tumors or primary tumors in the proximity and either cannot have repeat XRT or refuse it. I've always thought of NMSC as a surgical disease -- obviously -- but there are many times that I wish XRT was a more palatable / viable / offered option for my practice.

 

[medgator]

Pardon my ignorance here but I've often wondered: given that any CA is a space occupying lesion... and if treatment is to be successful, the entire lesion has to be killed, what happens with healing? I know the three dimensional aspects of these tumors as I am stuck chasing them down daily... and I know that if treatment is to be successful, tumor has to leave, adnexal structures take the friendly fire and are diminished, and atrophy of the dermis is appreciated... the histologic effects of radiation are well recognized... how (physically) is it that cosmesis (or even function, depending on the area treated) is retained if the mass effect of the tumor is anything other than minimal? I've never been given an answer to this question -- and am genuinely curious. Everywhere I have trained or practice has always treated XRT as the red headed step child -- second line, reserve therapy for primary tumors with aggressive features or complicating patient psychology, intraneural or intravascular involvement, recurrent with field effect, high metastatic risk, etc., so I have had precious little good exposure to it. Community docs have burned people up, creating one helluva mess when they have secondary tumors or primary tumors in the proximity and either cannot have repeat XRT or refuse it. I've always thought of NMSC as a surgical disease -- obviously -- but there are many times that I wish XRT was a more palatable / viable / offered option for my practice.

The healing is fine, mostly, although can be problematic in diabetics/vasculopaths/smokers just like with surgery. Radiation generally does better though in terms of healing risk and function in my experience.

How do you treat large lower extremity pretibial/shin scc or bcc lesions?

 

[MOHS_01]

The healing is fine, mostly, although can be problematic in diabetics/vasculopaths/smokers just like with surgery. Radiation generally does better though in terms of healing risk and function in my experience.

How do you treat large lower extremity pretibial/shin scc or bcc lesions?

Begrudgingly

Mostly surgically - have the XRT discussion, have been burned twice and don't push it nearly as hard as I did a few years ago.

Maybe my XRT guys are as bad as your surgeons are (apparently).


Sent from my iPhone using SDN mobile

 

[medgator]

Begrudgingly

Mostly surgically - have the XRT discussion, have been burned twice and don't push it nearly as hard as I did a few years ago.

Maybe my XRT guys are as bad as your surgeons are (apparently).


Sent from my iPhone using SDN mobile

Possibly lol. I get a lot of pretibial lesions, mostly older pts often diabetic +/- vasculopathy from derms/surgeons who aren't excited about operating. Some good responses, generally heals up well, may sometimes take a couple months. I usually treat them with standard course over 6-6 1/2 weeks, unlike some of the nasal and ear lesions which can be hypo-fractionated over 4 1/2 weeks.

There is a good discussion of non melanoma skin cancer at nccn.org, it's free to join if you haven't read the guidelines already

 

[MOHS_01]

​

Possibly lol. I get a lot of pretibial lesions, mostly older pts often diabetic +/- vasculopathy from derms/surgeons who aren't excited about operating. Some good responses, generally heals up well, may sometimes take a couple months. I usually treat them with standard course over 6-6 1/2 weeks, unlike some of the nasal and ear lesions which can be hypo-fractionated over 4 1/2 weeks.

There is a good discussion of non melanoma skin cancer at nccn.org, it's free to join if you haven't read the guidelines already

Thanks. Yes, I believe many of my colleagues are... how do I say it... primadonnas when it comes to handling anything the least bit difficult or with the risk of being complicated. It's both function of mindset and the fact that they have always been busy enough that they are accustomed to cherry picking... although I understand the desire to avoid two areas in particular: the shin as you describe and atrophic, bald heads in elderly gentlemen. I don't quite understand how you kill the cancer and avoid ulceration though -- truly wish I had more exposure to this as I would love to have better / more options when whatever I have to offer is a load to carry for the patient... particularly when they are at a time in their life that they cannot really take care of things like they once could and when complications can spiral into something worse.

 

[evilbooyaa]

Thanks. Yes, I believe many of my colleagues are... how do I say it... primadonnas when it comes to handling anything the least bit difficult or with the risk of being complicated. It's both function of mindset and the fact that they have always been busy enough that they are accustomed to cherry picking... although I understand the desire to avoid two areas in particular: the shin as you describe and atrophic, bald heads in elderly gentlemen. I don't quite understand how you kill the cancer and avoid ulceration though -- truly wish I had more exposure to this as I would love to have better / more options when whatever I have to offer is a load to carry for the patient... particularly when they are at a time in their life that they cannot really take care of things like they once could and when complications can spiral into something worse.

Basically what happens is that as the cancer dies slowly, over time (a la 6.5 weeks), the body has time to fill in the dying areas with new tissue, or at worst, scar. Full effects of radiation aren't seen on tumor for months after treatment frequently, and that's why, long after the toxicity from radiation (skin in this case) has worn-off, there can still be tumor kill.

Basically, radiation isn't like a laser or thermal ablation where it immediately just necroses everything in an area (thus leading to potential poor cosmetic outcome). At a high-enough dose you are concerned about long-term fibrosis, but frank ulceration in the acute setting due to radiation is a grade 4 toxicity (grade 5 = patient died) and is incredibly rare.

 

[MOHS_01]

Basically what happens is that as the cancer dies slowly, over time (a la 6.5 weeks), the body has time to fill in the dying areas with new tissue, or at worst, scar. Full effects of radiation aren't seen on tumor for months after treatment frequently, and that's why, long after the toxicity from radiation (skin in this case) has worn-off, there can still be tumor kill.

Basically, radiation isn't like a laser or thermal ablation where it immediately just necroses everything in an area (thus leading to potential poor cosmetic outcome). At a high-enough dose you are concerned about long-term fibrosis, but frank ulceration in the acute setting due to radiation is a grade 4 toxicity (grade 5 = patient died) and is incredibly rare.

Thank you. This reinforces my opinion of my local options -- ulceration would almost be considered frequent locally.

 

[medgator]

Was just looking at the NCCN guidelines on skin CA (SCC), and noticed a line in the radiation section:

"There are insufficient long-term efficacy and safety data to support the routine use of electronic surface brachytherapy"

I know a lot of people do HDR for skin, considering NCCN is pretty all encompassing when it comes to treatment techiques, does anyone have any concerns regarding that?

 

[radiaterMike]

Was just looking at the NCCN guidelines on skin CA (SCC), and noticed a line in the radiation section:

"There are insufficient long-term efficacy and safety data to support the routine use of electronic surface brachytherapy"

I know a lot of people do HDR for skin, considering NCCN is pretty all encompassing when it comes to treatment techiques, does anyone have any concerns regarding that?

I think this is explicitly referring to *electronic* brachytherapy and not HDR. ASTRO and the American Dermatology Assoc. have similar statements. The ASTRO model policy for HDR and LDT brachytherapy includes skin cancer.


Sent from my iPhone using SDN mobile

 

[medgator]

I think this is explicitly referring to *electronic* brachytherapy and not HDR. ASTRO and the American Dermatology Assoc. have similar statements. The ASTRO model policy for HDR and LDT brachytherapy includes skin cancer.


Sent from my iPhone using SDN mobile

Good pickup. Is there any reason why electronic is frowned upon?

 

[radiaterMike]

Good pickup. Is there any reason why electronic is frowned upon?

Others may know more. I think part of it is related to poorer understanding of dosimetry. Perhaps a bigger issue is the lack of regulation (it doesn't fall under NRC regulations and can be administered by non radiation oncologists). Part of it is related to the abuse of it (EBT in lieu of surgical management when surgery was not contraindicated) due to favorable reimbursement which has since been reversed.

Edit ....
Found these:

https://www.aad.org/Forms/Policies/Uploads/PS/PS-Electronic Surface Brachytherapy.pdf

https://www.aad.org/Forms/Policies/Uploads/PS/PS Superficial Radiation Therapy.pdf


Sent from my iPhone using SDN mobile

 

[medgator]

Others may know more. I think part of it is related to poorer understanding of dosimetry. Perhaps a bigger issue is the lack of regulation (it doesn't fall under NRC regulations and can be administered by non radiation oncologists). Part of it is related to the abuse of it (EBT in lieu of surgical management when surgery was not contraindicated) due to favorable reimbursement which has since been reversed.


Sent from my iPhone using SDN mobile

Turf battles seem like a weak reason to neg it in the NCCN. Conceptually, I don't see how it's any different than using Co-60 vs a linac to do brain met SRS.

 

[radiaterMike]

See links above. More than turf battles particularly with AAD weighing in on it


Sent from my iPhone using SDN mobile

 

[berag]

Electronic brachytherapy for skin cancer has been associated with overuse for billing reasons. Dermatologists (sometimes coordinating with a rad onc) could use it for small lesions instead of EC&D or liquid nitrogen, and bill much more. Here's some outright fraud:
$18 Million Judgment Entered In Palm Beach Dermatologist Medicare Fraud Lawsuit

 

[medgator]

Electronic brachytherapy for skin cancer has been associated with overuse for billing reasons. Dermatologists (sometimes coordinating with a rad onc) could use it for small lesions instead of EC&D or liquid nitrogen, and bill much more. Here's some outright fraud:
$18 Million Judgment Entered In Palm Beach Dermatologist Medicare Fraud Lawsuit

Way more egregious than just the ebt issue, I think that case was posted in another thread before

 

[medgator]

See links above. More than turf battles particularly with AAD weighing in on it


Sent from my iPhone using SDN mobile

Now I get it

Electronic Brachytherapy Opportunities

Has got to be even more boring than staffing a urorads center

 

[nkmiami]

there is guy in south florida who puts brachy units in vans and takes them to nursing homes to treat small basal cells b.i.d- sometimes.

 

[seper]

Does anyone know why did the company limit energy to 50 kV? Dosimetry limits applications of this.

 

[radiaterMike]

Does anyone know why did the company limit energy to 50 kV? Dosimetry limits applications of this.

Not sure if this is the reason but low energy allows for no room shielding or NRC oversight.


Sent from my iPhone using SDN mobile

 

[Reaganite]

I could have retired filthy had I whistleblown on all the craziness I saw and heard about during the heyday of electronic brachy. The amount of sheer fraud going on at that time by derms and sometimes complicit rad oncs (I say sometimes because some derms stopped using radoncs) was insane. At that time, these cases were paying like 20k a pop. Imagine 1 old guy with 2 small skin cancers. There's 40k if u treat them separately. Then imagine a mohs surgeon who was doing 40 mohs a week converting all his cases to xoft...oh Yeah, and also colluding with his dermatopathologist to overcall benign lesions...That's just one example...

 

[MOHS_01]

I could have retired filthy had I whistleblown on all the craziness I saw and heard about during the heyday of electronic brachy. The amount of sheer fraud going on at that time by derms and sometimes complicit rad oncs (I say sometimes because some derms stopped using radoncs) was insane. At that time, these cases were paying like 20k a pop. Imagine 1 old guy with 2 small skin cancers. There's 40k if u treat them separately. Then imagine a mohs surgeon who was doing 40 mohs a week converting all his cases to xoft...oh Yeah, and also colluding with his dermatopathologist to overcall benign lesions...That's just one example...

Should still. Seriously, these ****ers need to burn - they're hurting patients... and all of us, ultimately.

It's bad enough that most of those who do 40/week are likely pushing the envelope with regards to appropriate use at best...


Sent from my iPhone using SDN mobile

 

[seper]

Not sure if this is the reason but low energy allows for no room shielding or NRC oversight.


Sent from my iPhone using SDN mobile

that's what I've meant, does going up to 150-200kV change the rules? As it stands, Xoft is much worse than Ir-192.


Sent from my iPhone using SDN mobile

 

[Gfunk6]

Just saw this gem on one of the e-brachy job ads on ASTRO;

Responsibilities include examining the patients skin, reviewing the pathology, writing the prescription and approving the treatment setup.

Also must be able to walk and chew gum

 

[Reaganite]

that's what I've meant, does going up to 150-200kV change the rules? As it stands, Xoft is much worse than Ir-192.
Sent from my iPhone using SDN mobile

The difference in energy is very important. 50kv requires no special shielding so you can bring the machine directly to a dermatologist's office. This allows for all sorts of joint venture type situations. Ir-192 can only be delivered in a vault.

 

[seper]

Yes, but how shielding would be dramatically different for 150kV? That's lumbar Xray, as far as I recall. Dosimetry in tissue would be far better with 150 kV.

The difference in energy is very important. 50kv requires no special shielding so you can bring the machine directly to a dermatologist's office. This allows for all sorts of joint venture type situations. Ir-192 can only be delivered in a vault.