Checklist to approve plans

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XRT_doc

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What sort of checklist do you use to approve radiation plans.

I go through this:
1. Dose constraints met
2. Look at the isodose curves to make sure PTVs adequately covered
3. Make sure no hot-spots outside of tolerance.

Anyone have any other things they look at before they approve a plan?
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Depends on the plan. Location of hot spot in IMRT plans. Size/location of 105% in breast cases. I usually try to glance at MU number in both 3D and electron cases to make sure they’re not grossly incorrect.
 
For SBRT, I like to get an actual value for conformity index. For IMRT, I just like to eyeball conformity, making sure things are reasonably tight and dose not spilling all over the place.
 
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For a lot of sites, with experience, I look at dose fall off at a certain distance that I know can be achieved. For instance prostate, you should be able to fall off by 50% 1 cm into the rectum. Thats how I know you got the best plan.
 
RickyScott said:
For a lot of sites, with experience, I look at dose fall off at a certain distance that I know can be achieved. For instance prostate, you should be able to fall off by 50% 1 cm into the rectum. Thats how I know you got the best plan.
Click to expand...

SPACEOAR > *

Why do you care about dose falloff into stool? Dose at the wall is what matters.
 
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seper said:
One should always start out by looking at beam angles and isodose distribution on CT slices, and only then jump to the DVH.
Click to expand...

I do this. However, there is a tremendous gray area where the "art" and "science" of radiation oncology intersect. With inverse planning and robust contouring of all organs at risk will we ever reach the point where we don't have to concern ourselves over specific arcs/beam angles and/or hot spots if all dose constraints are met?
 
Gfunk6 said:
I do this. However, there is a tremendous gray area where the "art" and "science" of radiation oncology intersect. With inverse planning and robust contouring of all organs at risk will we ever reach the point where we don't have to concern ourselves over specific arcs/beam angles and/or hot spots if all dose constraints are met?
Click to expand...

Becomes efficiency related. For example, doing multiple fields on a palliative non sbrt case when APPA will do, chewing up machine time, making pt remain on the table longer than necessary. Or doing two clockwise arcs or something where the machine is spending extra time moving around for no reason.

Efficiency will become more important in the era of APM and bundles.

Time is money, literally, when you are spending extra minutes yourself, paying the therapists, office staff etc to be there
 
No, there is not way to fully relegate this to the computer +/- dosimterist yet. For example, an arc going though non-reproducible flabby pannus in rectal IMRT. Looks fine on the DVH.

Gfunk6 said:
I do this. However, there is a tremendous gray area where the "art" and "science" of radiation oncology intersect. With inverse planning and robust contouring of all organs at risk will we ever reach the point where we don't have to concern ourselves over specific arcs/beam angles and/or hot spots if all dose constraints are met?
Click to expand...
 
Thanks for posting this and the article!

What beam angles for IMRT? Aren't you all doing VMAT planning for IMRT?
Dose constraints met - this is on scorecard
PTV coverage - this is on scorecard. What are you looking for on axials? Asking for myself, because I look as well, but if my goal is met, I'm not sure what I'd reject, but I do this not knowing exactly why I do it. EDIT: article delineates this nicely.
Hot spots outside of tolerance - this is on scorecard
105% in breast - on scorecard
MU number - hmm, I guess I should look at that. Not sure exactly what to look for? Elaborate?
SBRT CI - scorecard
Axials first then scorecard - why exactly, Seper, other than dogma or routine? I don't understand. EDIT: from article, I see explanation and pasted below.
1 cm from rectum/50% - contour rectum, remove all but 1 cm - put on scorecard
SpaceOar - yes sir!
Efficiency - yes, this is important. More about initial instruction to dosi, rather than at plan approval? I sort of know what should be AP-PA and what should be multi-field. All the things you're saying should be directed pre-plan, I think?
Arc going through flabby pannus - good point. Although, should be considered pre-plan, right?

...

Useful article!!

To your points, from article:

For 3-dimensional (3D) plans, it is important to ensure that the fields are entering the body at angles that avoid entry through excess normal tissue. In addition, beam shaping with multileaf collimators (MLCs) or other devices should be appropriate for a given target and surrounding OARs. This can be evaluated by directly visualizing each field using the beam’s eye view and is also based on 3D isodose lines overlaid on the computed tomography (CT) images. When treating an area in the neck or thorax, for example, one should ensure the beams are not entering through the shoulders/arms or exiting the oral cavity unnecessarily. For intensity-modulated radiation therapy (IMRT) plans, one should consider the number of fields and their point of entry through the body and fluence patterns. Assessing the field arrangement and collimation may subsequently become important if target volume coverage or OAR dose limits are not optimal and may be improved with additional fields or different beam entry angles.

The number of fields or arcs is also a key factor in the treatment time. A patient undergoing a palliative radiation treatment may not be able to lie on the treatment table for long periods, and a faster treatment may be preferable. Radiation oncologists should also consider that patient mobilization and internal organ motion are increased with longer treatment times.


The DVH must be used with caution. The DVH cannot assess the appropriateness of the targets and OARs. The DVH could report 100% coverage of the PTV by the prescription dose, but the PTV could be delineated incorrectly. Alternatively, 95% PTV coverage may not be met, but there may be a compromise between PTV coverage and OAR constraints, with an accepted sacrifice in PTV coverage to avoid unacceptable toxicity to a surrounding critical OAR. Furthermore, there may be excessive dose spillage through structures not reported within the DVH. Because this information cannot be obtained from the DVH alone, we recommend evaluating the 3D graphical plan qualitatively before proceeding to the DVH.
 
I definitely do not arc every imrt plan. For example, if I’m arcing a stage iii lung it’s only because I wasn’t happy with a static field and the arc looks comparable but is just easier to deliver.

I look at MU just to make sure it isn’t grossly incorrect. Trying to give 300 cGy APPA? I figure it should be a little more than 300 MU total, roughly half from each field. If I see 600 or 200 MU total, I know something is off. Ditto electrons, even with small blocks. I have a good physics team, but I sign my name to the plan.

Bonus: that trick is also helpful if you ever find yourself somewhere doing a clinical setup/treatment, such as on call. Hand calcs arent something I do often (ever) so I’ll give them shot, but it’s easy to tell if they’re way off. When worse comes to worse, just give like 160 from the front and back and you’ll be giving something close to 300 cGy to misplane. They can figure out exactly what you did Monday when staff comes back.
 
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Gfunk6 said:
I do this. However, there is a tremendous gray area where the "art" and "science" of radiation oncology intersect. With inverse planning and robust contouring of all organs at risk will we ever reach the point where we don't have to concern ourselves over specific arcs/beam angles and/or hot spots if all dose constraints are met?
Click to expand...
That era is already here, and it's a nice, relaxing, chill era. But it is body site specific. For example, touching on points already mentioned, it's kind of a unique little deal with breast using electronic tissue compensation (ie 2 beam tangent IMRT lite):
1) Spend a lot of time looking at beam entry/exit my dosim's have chosen (how much heart exposure? how much lung? cavity covered? we want the fields "just right" esp if there are sclv matches etc)
2) Is there >110% dose anywhere? Don't like that. I look at the >105% isovolumes: ideally these are small-ish.
3) I make sure there is adequate skin flash for the fluences chosen/optimized.
4) Let's say I'm doing 2.65 Gy per fraction, ie ~1.32 Gy per tangent, ie 130 MU minimum per beam. If I see a beam >260 MU (greater than 2:1 MU:cGy ratio) it would tend to indicate a weird little niggling unnecessary fluence hot spot in the beam that needs to be smoothed out. If I see >390MU (greater than 3:1 MU:cGy ratio) per beam I know the plan needs probably redone (I use dMLCs obviously). Less MUs = less patient exposure (ALARA) = quicker treatment. If it's a 1.5 MU:cGy ratio it's usually a pretty choicy plan and I know I'm working with a dosimetrist who knows her stuff.
ROFallingDown said:
The DVH must be used with caution. The DVH cannot assess the appropriateness of the targets and OARs. The DVH could report 100% coverage of the PTV by the prescription dose, but the PTV could be delineated incorrectly. Alternatively, 95% PTV coverage may not be met, but there may be a compromise between PTV coverage and OAR constraints, with an accepted sacrifice in PTV coverage to avoid unacceptable toxicity to a surrounding critical OAR. Furthermore, there may be excessive dose spillage through structures not reported within the DVH. Because this information cannot be obtained from the DVH alone, we recommend evaluating the 3D graphical plan qualitatively before proceeding to the DVH.
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100% true and was said when the DVH was being birthed: "DVHs show promise as tools for comparing rival treatment plans for a specific patient by clearly presenting the uniformity of dose in the target volume and any hot spots in adjacent normal organs or tissues. However, because of the loss of positional information in the volume(s) under consideration, it should not be the sole criterion for plan evaluation."
 
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I also review PTV coverage on DVH (not sure if you include that in your dose constraints)

I review isodose on axial just to double-confirm that I didn't make any errors in my PTV delineation.

For the discussion above - I don't routinely evaluate beam angles when using VMAT. For 3D I've told my dosimetrists what field arrangements to use, and if they have an alternative they usually show me before plan verification.

I do think glancing at MUs on a 3D plan is good practice although I don't do it as much as I should. I frequently don't do it for IMRT plans because there can be significant modulation depending on target placement and OAR constraints.
 
Sometimes, I think checklist prior to contouring is more useful, specifically to read H and P, and look at radiology scans and reports.
 
evilbooyaa said:
I do think glancing at MUs on a 3D plan is good practice although I don't do it as much as I should. I frequently don't do it for IMRT plans because there can be significant modulation depending on target placement and OAR constraints.
Click to expand...
Neat little throw-away study for the Red Journal: how MUs vary significantly in identical clinical scenarios by dosimetrist.
 
medgator said:
Yup, a 5-7 field imrt plan looks better in some cases. I've seen that in L breast with nodes and some h&n/lung cases
Click to expand...

pelvic + groins as well, as in anal cancer imo. Arcs are great for round tumors in the center of the body (prostate), but they aren’t great for everything.
 
Mandelin Rain said:
I definitely do not arc every imrt plan. For example, if I’m arcing a stage iii lung it’s only because I wasn’t happy with a static field and the arc looks comparable but is just easier to deliver.

I look at MU just to make sure it isn’t grossly incorrect. Trying to give 300 cGy APPA? I figure it should be a little more than 300 MU total, roughly half from each field. If I see 600 or 200 MU total, I know something is off. Ditto electrons, even with small blocks. I have a good physics team, but I sign my name to the plan.

Bonus: that trick is also helpful if you ever find yourself somewhere doing a clinical setup/treatment, such as on call. Hand calcs arent something I do often (ever) so I’ll give them shot, but it’s easy to tell if they’re way off. When worse comes to worse, just give like 160 from the front and back and you’ll be giving something close to 300 cGy to misplane. They can figure out exactly what you did Monday when staff comes back.
Click to expand...
If I'm using inverse planning, I try to arc everything humanly possible. Less treatment time for the patient and less opportunity for unforeseen intrafractional events because the treatment time is quicker. Also allows ability to treat more pts on the linac. Most dosimetrists will get comparable conformality with arc as compared to static, if not better.
 
Yes and you can vector out certain ranges of angles if you want to preserve the advantage of step and shoot IMRT. I have never done S&S and I don't really plan to.
 
evilbooyaa said:
Yes and you can vector out certain ranges of angles if you want to preserve the advantage of step and shoot IMRT. I have never done S&S and I don't really plan to.
Click to expand...

Once we got it, never looked back. I’d be surprised to see what advantages people are talking about. Maybe there is data on it? But speed of treatment is definitely a factor wrt interfractional variability.
 
KHE88 said:
No such thing as IMRT-lite. This is called a 3D plan. Use of the word IMRT necessitates inverse planning.
Forward planned IMRT called IMRT is fake news. Forward planned IMRT billed as IMRT is fraud.
Click to expand...

Oh god please not this again
 
Mandelin Rain said:
pelvic + groins as well, as in anal cancer imo. Arcs are great for round tumors in the center of the body (prostate), but they aren’t great for everything.
Click to expand...
Certainly that used to be the case, but with each version of eclipse (if you are on varian) VMAT has improved (also dosimetrists gaining more experience). In head and neck, VMAT, has been better in most cases over the last several years in my experience. Chest is very controversial and never used to deliver VMAT for stage III Nsclc until recently, but over last year have seen some good plans
 
VMAT vs. fixed-angle IMRT is an old battle. There is a large body of literature, and I used to write about it as well. Plan comparison is highly dependent on planning system, input, and dosimetrist's skill.
In the end of the day, I use VMAT for everything, but pay attention to where arcs are entering the patient.
 
KHE88 said:
No such thing as IMRT-lite. This is called a 3D plan. Use of the word IMRT necessitates inverse planning.
Forward planned IMRT called IMRT is fake news. Forward planned IMRT billed as IMRT is fraud.
Click to expand...
Have you submitted a letter to the editor yet?

www.ncbi.nlm.nih.gov

A multicenter randomized trial of breast intensity-modulated radiation therapy to reduce acute radiation dermatitis - PubMed

Breast IMRT significantly reduced the occurrence of moist desquamation compared with a standard wedged technique. Moist desquamation was correlated with increased pain and reduction in the quality of life.
www.ncbi.nlm.nih.gov www.ncbi.nlm.nih.gov
 
OH okay. Then you are agreeing with KHE88 that it is not to be billed as IMRT. WE HAVE CONSENSUS!
 
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ROFallingDown said:
OH okay. Then you are agreeing with KHE88 that it is not to be billed as IMRT. WE HAVE CONSENSUS! INSHALLAH, shall we celebrate with some fesenjen??
Click to expand...
Just because we don't bill sims with imrt doesn't mean we stop calling them sims anymore. The work is being done, it is just not being billed as such.

At some point people called it imrt, bottom line and you are modulating the beam with subfields etc. and I think that is scarbtj's point

But yes I wouldn't bill it as imrt, even though papers in the JCO referred to that very technique as "IMRT"
 
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evilbooyaa said:
Oh god please not this again
Click to expand...
put me in coach
KHE88 said:
No such thing as IMRT-lite. This is called a 3D plan. Use of the word IMRT necessitates inverse planning.
Forward planned IMRT called IMRT is fake news. Forward planned IMRT billed as IMRT is fraud.
Click to expand...
"Back to Mono" is not an album about the Epstein-Barr virus* and forward planned IMRT is just IMRT. Not "fraud." Medicare has defined forward planned IMRT as IMRT in the past:

77301 Intensity Modulated Radiation Therapy (IMRT) plan, including dose-volume histograms for target and critical structure partial tolerance specifications. (Dose plan is optimized using inverse or forward planning technique for modulated beam delivery (e.g., binary dynamic MLC) to create highly conformal dose distribution.

Over time, the forward planned verbiage was lost in most LCDs but there's never been express guidance that the old guidance has been invalidated AFAIK. And as you probably know forward planned IMRT is just called IMRT in all the literature ("All treatment groups received simple forward-planned intensity-modulated radiation techniques to optimise dose homogeneity"). But who cares what we call it. Call it the goober. The thingy. Speech is not illegal! The kafkaesque situation is that electronic tissue compensation is inversely optimized, but everyone calls it forward planning, and even though it's inversely optimized if you tried to bill it as such everyone's, like, head would explode and they'd post "that's fraud" on the Internet 😉

*non-sequitur
 
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Well .. if 77301 says modulation by forward planning counts, I stand corrected. You should submit as IMRT. If you're not, you're underbilling!!

Would this get approved? Sounds like it would be a tough sell. But, that's what Medicare says... is this a recent document?
 
ROFallingDown said:
Well .. if 77301 says modulation by forward planning counts, I stand corrected. You should submit as IMRT. If you're not, you're underbilling!!

Would this get approved? Sounds like it would be a tough sell. But, that's what Medicare says... is this a recent document?
Click to expand...
Not recent at all.* There'd be your "in" for fraud claim.
So here's what I think.
You could rationally and legally bill it as IMRT. Because the whole damn world (besides a few American rad oncs) agrees it's called IMRT.
Someone could probably get an (unscrupulous) lawyer, maybe at the govt level even, to bird dog the case.
It would be an active case and a huge PIA for the person billing it as IMRT.
The fraud case would fail (nost do nowadays when there are ambiguities), but you might have to do a simple refund of the money.

* However it is obviously currently extant on the government's website.
 
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KHE88 said:
No such thing as IMRT-lite. This is called a 3D plan. Use of the word IMRT necessitates inverse planning.
Forward planned IMRT called IMRT is fake news. Forward planned IMRT billed as IMRT is fraud.
Click to expand...

I keep thinking about that IMPORT LOW breast paper that used “forward planned IMRT” and thought to myself gosh what a weird title.
 
RadsWFA1900 said:
I keep thinking about that IMPORT LOW breast paper that used “forward planned IMRT” and thought to myself gosh what a weird title.
Click to expand...
In reality there is no inverse planning. If the definition of a priori literally means "from the former," we humans all make many more planning delivery choices than the computer. "Inverse planning" is a misnomer. All IMRT is forward planned. Oh well. We're stuck with it I suppose.

INVERSE PLANNING...
Something that is optimum cannot be bettered by definition. Therefore the optimum plan is the best that could ever be obtained for treating a particular patient with a particular external shape, location of disease and arrangement of internal organs. I propose the view that this optimum plan is unachievable and that in practice this does not matter. To arrive at the optimum plan one would have to investigate the use of: (i) all types of irradiation (protons, carbon ions, photons…); (ii) of all energies (continuous not just those we have available); (iii) all possible numbers of beams from 1 to infinity; (iv) all possible ranges of fluence levels; (v) all possible beam geometry shapes; (vi) all possible fractionation schemes …and so on. It is totally apparent that as "optimizers" we cannot and do not do this. We are constrained by: (i) the beams available on our machines; (ii) the need to keep the number of beams deliverable within some specified delivery timeslot; (iii) the delivery mechanics available to us (which links in to the fluence level issue); (iv) the collimation available from the machine; (v) the need to treat in the daytime not at night; (vi) the time available for planning…and so on. In practice the planner and doctor have already considerably reduced the optimization search space by making a priori choices, e.g. the choice to work with photons at 6 MV, with say 5 beams from certain specified directions, with a preset number of fluence levels, with the MLC of a particular manufacturer, with a specified fractionation scheme. Then all that is left to optimize is the beam profile subject to the constraints set. When we write of "optimization" we mean most certainly ‘‘constrained optimization."
 
thecarbonionangle said:
Are people really billing for IMRT in field in field in breast?
Click to expand...
I bet almost no one in America is doing what we'd call field-in-field IMRT (when done properly it's too time-consuming/laborious). In the Eclipse space I use electronic tissue compensation. Some have called this forward planning; again, in reality this is not correct. It's a method by which a fluence is computer generated where there is a single optimization parameter: to create a uniform dose in a (non-Euclidean) plane containing the isocenter which is perpendicular to the given beam. Everyone was billing this as IMRT in the early IMRT days. One day, some smart people said, "Hey this is not IMRT." That really dropped the proverbial turd in the pool. To go along with the new groupthink most people quit billing it that way. I wager some people do still bill IMRT with electronic compensation.
 
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thecarbonionangle said:
Are people really billing for IMRT in field in field in breast?
Click to expand...

I have seen several instances of patients treated outside at private practices getting tangential field-in-field breast RT and it was labeled (and most certainly billed) as "IMRT"
 
medgator said:
No, but it is still IMRT per the literature and scarbtj has provided CMS LCD links indicating it might actually be kosher to do so
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thanks but I am not making any billing/coding judgments per se. Although sometimes the things we think we know just ain't so. And even if CMS says it's kosher... that doesn't mean it's actually kosher (see: supervision)!
 
dieABRdie said:
I have seen several instances of patients treated outside at private practices getting tangential field-in-field breast RT and it was labeled (and most certainly billed) as "IMRT"
Click to expand...

Sliding window (inverse planning of infinite field in fields) is 'tangential IMRT'.

Deleting food discussions. Take it to a new thread, we have enough off-topic nonsense in this forum.
 
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