Hypofrac in DCIS

[Gfunk6]

Advertisement - Members don't see this ad

The Whelan trial did not include DCIS. ASTRO guidelines for breast hypofrac in 2010 have divided expert opinion on whether hypofrac is appropriate for DCIS.

I know there is retrospective data and prospective data is pending. However, what do you all do now?

In my clinic, I offer conventional fractionation (25 fractions) for DCIS and give the patient the above caveats. If they absolutely insist on hypofrac, I will generally relent because the data is not great either way. However, I am increasingly wondering if the extra week and a half is worth it.

 

[deleted4401]

You're absolutely right that Whelan didn't include DCIS, but they did let people with associated intraductal disease onto the trial. And, the ASTRO guidelines even when updated really hemmed and hawed. Whelan's group has retrospective data for hypofx for DCIS, and NYU has a series, as well. Whelan's incidentally finds the same thing in DCIS as in IDC - the higher grade disease seems to perform worse with hypofx.

I don't see any logical reason why we would treat non-invasive disease more aggressively than invasive disease. It's like saying there was no randomized trial comparing mastectomy to lumpectomy for DCIS, so we shouldn't do BCS for it.

I really think it's economics.

That being said, I generally save it for older women or people with transport issues. And, I don't recommend it for people that I would boost (+margins, young patients).

S

 

[Ursus Martimus]

Show me the data, as well, for DCIS boost. RTOG 1005 might help sort things out:
Aim: To determine whether an accelerated course of hypofractionated WBI including a concomitant boost to the tumor bed in 15 fractions following lumpectomy will prove to be non-inferior in local control to a regimen of standard WBI with a sequential boost following lumpectomy for early-stage breast cancer patients.

allows DCIS.

 

[medgator]

There's a paper from Canada that specifically look at DCIS and HypoFx.

http://www.ncbi.nlm.nih.gov/pubmed/20400190?dopt=Abstract

Based on that, I will offer it as an option for patients who can't make it in for Standard Fx, but I really only bring it up if that's an issue

 

[deleted4401]

So we had discussed an APBI case in tumor board, and decided she wasn't a suitable candidate... but was thinking...

The logic in general about APBI is interesting. The rationale for doing it is that 80-90% of recurrences are within a 1cm of the lump cavity, so there is no reason to treat the remainder of the breast...

So, how they came up with the risk factors makes no sense to me. Is there any reason to believe that node positivity infers a greater risk of elsewhere in the breast recurrence that justifies treating the whole breast? Or that a close margin predicts for elsewhere in the breast recurrence? Or age... Of course we know that these are risk factors for recurrence, but that doesn't stop us from recommending BCS+RT for 35 year old woman with T2N1 disease with a margin less than 2mm. We just explain that there is a higher risk of recurrence. I don't get why it would be any different with APBI.

The target and area at risk is the same. The recurrence risk may be greater, but the dose is not any lower. In fact, for a positive margin, the area closest to the balloon gets a much higher dose than it would with external beam, and over a shorter course of time. One would think that these patients would be even better candidates for it. It's just seems pretty arbitrary.

Am I missing something?

S

 

[Palex80]

HypoFx for DCIS is an option for older patients in my opinion, when one does not have any big concerns concerning late cosmetic effects. We now have 10 year data from the START B trial showing cosmesis with HypoFX being as good as with normal Fx, but who knows what it's gonna be like in another 10 years.
Therefore I will offer HypoFx to patients >60 years of age, if they want it.

The question of boost for DCIS may answered by the large IBCSG trial currently running, but we'll probably have to wait around 10 years from now to get any valuable results. We are recruiting for the trial.

 

[iradi8u]

I think 10-05 is going to be a game-changer and I predict that we'll be treating most women with a hypofractionated regimen with concommitant boost technique in the near future.

We will rarely treat a DCIS per Whelan, but only if she's >60 years old, and only if we're not going to convince her to be treated otherwise.

As far as APBI and nodes,we tend to treat nearly all node+ patients with locoregional XRT, so it makes sense not to treat with a balloon or multicath.