Daily imaging if treating like IMPORT-LO

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xrt123

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Wondering if anyone changes daily imaging if treating like Import Lo protocol. My typical whole breast treatment imaging is Right sided-weekly Port, but Left -daily KV/DIBH. Anyone changing there imaging or how you mark the breast/scar if treating like Import Lo? if so have you run into any insurance issues?
 
I do daily imaging with partial breast 30/5, but with import low I've stuck with weekly (on R sided or with non-breath hold L sided). THe margins are so huge that it's damn near whole breast anyway.

If a clear, small-ish seroma/CTV I typically do 30/5. Daily imaging is typically reimbursed, either G6002 for kv or a 77014 for a spotlight CBCT. With larger seromas/targets I've done 40/15 style import low with weekly imaging for R side, daily imaging for L side if doing DIBH.

I don't typically bill G6002 code for the daily imaging on whole breast DIBH (often just take a tangential kV gate triggered port with weekly orthogonal), but do bill it if doing daily Kv's on the occaisional chest wall comprehensive case where using IMRT.

I also typically image just like you for standard WBRT : R sided weekly, L side DIBH daily kv.
 
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So just off top of my head I think daily imaging w/ 30/5, vs no daily imaging with 50/25 e.g., treats the doctor more than the patient. Not a significant risk or toxicity difference with either fractionation IMHO, except 30/5 probably inherently a lot safer because reduced tx volume. And you guys are prejudiced against right sided breast cancer patients lol (they don't "deserve" daily IGRT?). Opinions dominate here way more than evidence. There exist, for me, two truisms: daily IGRT decreases wrong-site/wrong-patient fractions vs non-daily IGRT, and daily IGRT improves treatment accuracy vs intermittent IGRT. Once APM gets here, I will do daily IGRT with reckless abandon.
 
Are you doing 2 field mini tangents for import low (per trial)....or something more conformal (5-6 fields...not Imrt, just more conformal)
 
scarbrtj said:
So just off top of my head I think daily imaging w/ 30/5, vs no daily imaging with 50/25 e.g., treats the doctor more than the patient. Not a significant risk or toxicity difference with either fractionation IMHO, except 30/5 probably inherently a lot safer because reduced tx volume. And you guys are prejudiced against right sided breast cancer patients lol (they don't "deserve" daily IGRT?). Opinions dominate here way more than evidence. There exist, for me, two truisms: daily IGRT decreases wrong-site/wrong-patient fractions vs non-daily IGRT, and daily IGRT improves treatment accuracy vs intermittent IGRT. Once APM gets here, I will do daily IGRT with reckless abandon.
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If I had right sided early stage breast cancer / DCIS and my rad onc told me they were going to cbct me daily for 15+ fractions I'd tell them to piss off. ALARA bro
 
radmonckey said:
If I had right sided early stage breast cancer / DCIS and my rad onc told me they were going to cbct me daily for 15+ fractions I'd tell them to piss off. ALARA bro
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Weekly port films could easily be "attacked" from ALARA standpoint too. Their ubiquity much more due to tradition than EBM, esp in case of breast where we could just have the MD come to room and confirm a daily clinical setup and take a standard photograph (vs an MV film) to confirm. No data to support daily IGRT for left-sided, conversely no data to support not doing daily IGRT on right-sided. In other words, ALARA a good argument to prevent daily IGRT for left-sided too.
 
The integral dose to the rest of the body in a young patient with extremely low risk disease is not worth the cbct. Yes you or I will likely never see the consequences of this but there is a small second malignancy risk here. Could easily do a treatment port during and get all the confirmation you need.

Disagree that there is no evidence that it matters in left breast cancer. I see many cases where even a 5mm shift into the heart would shoot the max and mean dose up significantly and we have evidence that heart dose matters.
 
radmonckey said:
Disagree that there is no evidence that it matters in left breast cancer. I see many cases where even a 5mm shift into the heart would shoot the max and mean dose up significantly and we have evidence that heart dose matters.
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"I see many cases..." Anecdotal! Not really EBM. My anecdotes are pretty good too! I see many right sided cases where a 5mm shift would shoot the lung V20 up a few percent and we have evidence V20 matters. Also I see many right sided cases where a 5mm shift would shoot the the PTV mean dose down and we have evidence that PTV dose matters... (I could go on, as you know!)
radmonckey said:
The integral dose to the rest of the body in a young patient with extremely low risk disease is not worth the cbct.
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The increased integral dose from daily CBCT over ~15fx is very minimal compared to the integral dose from the EBRT itself. You know this. It's kind of like having a private jet, being simultaneously concerned about climate change, and then saying "The CO2 from my private jet is warming the earth too much; thus I will only use it sparingly."
 
scarbrtj said:
The increased integral dose from daily CBCT over ~15fx is very minimal compared to the integral dose from the EBRT itself.
Click to expand...

This is true per the literal definition of integral dose, however you could potentially be doubling or tripling the dose to the contralateral lung and breast. Again, ALARA.

Also I'm sure one could find some paper on setup variability in breast cancer and couple that with the data on heart dose and lung dose to construct a less anecdotal more EBM argument for left vs right IGRT. But hey if you can't get zero dose to everything, why try right?
 
radmonckey said:
This is true per the literal definition of integral dose, however you could potentially be doubling or tripling the dose to the contralateral lung and breast. Again, ALARA.
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This is really key to the discussion of course. There's ~1% out of field scatter in general from the EBRT, but that's based on MUs and not strictly dose. In other words, giving 42.5Gy needs about ~84Gy of MUs and we will see ~0.8Gy mean dose in that other lung from EBRT alone, worst case I imagine. If you do IMRT(!!!) as they did in IMPORT-LOW it could be a higher MU/Gy ratio. But be that as it may the daily CBCT dose is about 2 cGy, times 15 = ~0.3 Gy lung dose from CBCT.

My point is, CBCT increases the contra (and ipsi!) lung dose "significantly," but probably not double, almost certainly not triple, that of EBRT itself here. And what else... well, one MD may use >10MV beams in breast (thus have some increased neutron output from machine) and never do daily CBCT. This would likely be "worse ALARA" than 6MV beams and daily CBCT.
 
SneakyBooger said:
I am an easy sell.

Who here treats keloids? Heterotopic ossification of bone (NSAID's better)? And so forth.

I do refuse to do CBCT with arthritis.

Well, so far.
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Well back to my climate analogy... maybe there are pluses and minuses with some increased CO2. And maybe there are pluses and minuses with the wee bit extra dose CBCT provides: no joke... may be treating some aches and pains etc. The thing about as low as reasonably achievable (ALARA)... "reasonable" is very subjective!

EDIT: Now we have data that hair dye/straightener second cancer risk >> CBCT second cancer risk ... "If I had right sided early stage breast cancer / DCIS curly hair and my rad onc told me they were going to cbct me daily for 15+ fractions straighten it I'd tell them to piss off"
 
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scarbrtj said:
Well back to my climate analogy... maybe there are pluses and minuses with some increased CO2. And maybe there are pluses and minuses with the wee bit extra dose CBCT provides: no joke... may be treating some aches and pains etc. The thing about as low as reasonably achievable (ALARA)... "reasonable" is very subjective!

EDIT: Now we have data that hair dye/straightener second cancer risk >> CBCT second cancer risk ... "If I had right sided early stage breast cancer / DCIS curly hair and my rad onc told me they were going to cbct me daily for 15+ fractions straighten it I'd tell them to piss off"
Click to expand...

I hope everyone follows your links. What fun learning!

After reading this I am all in on daily CBCT for keloids:

1575664713878.png
 
Haha I love unconventional thoughts. What if... what if... the reason cancer patients are living longer (ie having less long-term mets) is due to "low-dose radiation baths" from things like multi-field IMRT, VMAT, but daily IGRT especially (our kV IGRT Xrays would have more RBE than the MV Xray beams technically). The alpha cell killing component (inherently irreparable and pretty unlucky for the cell) of alpha/beta seems to shoot up in the low-dose region. Warning: very unexplored region of radiation oncology.
 
The next ALARA maneuver in breast RT? Will seriously screw up kV CBCTs most likely though.

 
scarbrtj said:
The next ALARA maneuver in breast RT? Will seriously screw up kV CBCTs most likely though.

Click to expand...



Do your CBCT without it, shift table, place "armour" afterwards (and hope patient doesn't move)?

We use a foam-block between legs when we treat sarcomas to do the planning CT and daily CBCTs and replace it immediately before each fraction with the "real" block. Perhaps they will invent something like that for the breast too...
 
What kind of blocks are you referring to with your sarcoma patients, Palex?
 
taserlaser said:
What kind of blocks are you referring to with your sarcoma patients, Palex?
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A lead block.
We put those sometimes between the legs when we treat one leg (mainly in sarcoma cases).
Then you can do whatever rotation you want (about 240° wise), without delivering significant dose to the contralateral leg.
 
Palex80 said:
A lead block.
We put those sometimes between the legs when we treat one leg (mainly in sarcoma cases).
Then you can do whatever rotation you want (about 240° wise), without delivering significant dose to the contralateral leg.
Click to expand...

I thought thats what you implied, but wasn’t sure. I should look at asking my physics team about that. Do a lot of arcs on those patients, and it does get tricky around genitals too. Thanks for the idea 🙂
 
Leg sarcoma is one of the sites where I do step and shoot to constrain the beam angles to keep dose off the contralateral leg. I never even considered whether you can put a big block in there. Does it work? How much does it weigh?
 
taserlaser said:
I thought thats what you implied, but wasn’t sure. I should look at asking my physics team about that. Do a lot of arcs on those patients, and it does get tricky around genitals too. Thanks for the idea 🙂
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Our physicists added a layer of soft material on the outer sides, it is supposed to absorb electrons that are produced by the block when you hit it with photons (in theory). There was some concern of excessive reaction on the skin of the irradiated leg that was "touching" the block.
Genitals are certainly an issue and you should probably talk with your technicians about it. You don't want to squizze anything down there. 😉
Our block is heavy, I'd say more than 10 lbs.
Small (and cheap) trick on how to make sure it doesn't fall:
7142ip6-h2L._SX466_.jpg

Magazine rack (you will have to get a thinner one, that one would probably be too heavy),

It work's well for us.

And you will need two blocks. One real one (for treatment) and one made out of foam (for CBCT & planning).
Only issue will be to make sure, the technicians don't forget to swap blocks after CBCT. We painted them with two different colors. 😉
 
Palex80 said:
A lead block.
We put those sometimes between the legs when we treat one leg (mainly in sarcoma cases).
Then you can do whatever rotation you want (about 240° wise), without delivering significant dose to the contralateral leg.
Click to expand...
clever
 
Recently ran across a discussion regarding this issue on Mednet so did a little more digging...

This group from Australia concluded daily CBCT decreased the risk of 2nd malignancy.

The analysis was of 50 Gy in 25 fractions.

DOI - 10.1007/s13246-017-0529-3

1631453687812.png
 
This article from the Society of French Radiation Oncologists states daily IGRT with hypo fractionation is "even more needed."

DOI :
1631454257887.png


1631454291513.png
 
This abstract from Johns Hopkins describes a partial CBCT protocol that reduces imaging related radiation exposure compared with standard EPID protocols.

LINK TO RED J ABSTRACT:
1631454655921.png
 
I see that daily ports and charging image guidance is the default approach in the region where I’m practicing. Probably, docs are overdoing it. Most people do not yet resort to daily CBCT, fortunately
 
I dunno @SneakyBooger. all this published data really runs counter to the mental heuristic that any sliver of radiation beyond what the traditional/conservative docs consider the bare minimum "appropriate" amount is surely causing terrible secondary malignancies without any benefit.

I counsel my patients to never set foot in the light from the Evil Daystar without wearing SPF500 or taking commercial flights.

...or going anywhere near Karunagappally, Kerala.
 
SneakyBooger said:
This publication from Wash U suggests daily CBCT minimizes risk of RT induced brachial plexopathy.
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I don't think so. This publication suggests that there is no difference in brachial plexopathy incorporating newer techniques. Even the dosimetry seems essentially equivalent.. That they would make an inference based on 4 vs 1 events here (when reviewing almost 500 patients) is not very smart.

Now I do buy that using PAB (and all of the selection bias that goes into treating with PAB) may be associated with higher risk of brachial plexopathy.
 
SneakyBooger said:
This abstract from Johns Hopkins describes a partial CBCT protocol that reduces imaging related radiation exposure compared with standard EPID protocols.

LINK TO RED J ABSTRACT:
View attachment 343290
Click to expand...
Is this method of estimating dose even appropriate? Isn't the most important measure integrated dose (or even more significant, dose to structures outside of the target)?

edit: Missed top of thread. It's all there.
 
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elementaryschooleconomics said:
I dunno @SneakyBooger. all this published data really runs counter to the mental heuristic that any sliver of radiation beyond what the traditional/conservative docs consider the bare minimum "appropriate" amount is surely causing terrible secondary malignancies without any benefit.
Click to expand...


"I am Locutus of Borg. Resistance is futile. Your life as it has been is over. From this time forward, you will service us."

– Locutus of Borg, 2366

1631468517962.png
 
seper said:
I see that daily ports and charging image guidance is the default approach in the region where I’m practicing. Probably, docs are overdoing it. Most people do not yet resort to daily CBCT, fortunately
Click to expand...
Ours do and I hate checking them during cross coverage. I miss a good old port film. Is the boob in the field? Yes, then treat. With CBCTs if the skin is on but the bones are off do I care? My feelings on breast are well known. Here is yet another way to make something easy a little bit harder ☹️
 
SneakyBooger said:
Recently ran across a discussion regarding this issue on Mednet so did a little more digging...

This group from Australia concluded daily CBCT decreased the risk of 2nd malignancy.

The analysis was of 50 Gy in 25 fractions.

DOI - 10.1007/s13246-017-0529-3

View attachment 343287
Click to expand...
Can you link to that mednet discussion. Searching for stuff there is unwieldy.

To add to the CBCT-in-breast milieu and especially appertaining to Intensity Modulated Partial Organ RadioTherapy (IMPORT) approaches

The IMPORT HIGH Image-guided Radiotherapy Study: A Model for Assessing Image-guided Radiotherapy
 
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