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SBRT might also be a reasonable approach....https://www.practicalradonc.org/article/S1879-8500(18)30081-X/abstract
There is a more robust experience than one might expect. Refer to the attached tables for experiences with both radiation and chemoradiation.
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My situation was pretty unique, to be honest. Patient was perfectly healthy to undergo surgery and had been on HT for some time when her primary progressed. She had already had metastatic disease for several years and had no evidence of progression other than in the breast. As a result, I thought her expected survival was to be measured in years rather than months. She adamantly refused to have a mastectomy, despite my really trying to convince her.
Most of the data we do have as shown above in Table 8 with RT alone (she refused any chemo at that time as well) has used traditional fractionation to ~70 Gy, and I was happy with both the short- and long-term outcomes of her case.
yeah for a select patient with a small tumor, this is the way I would think about going. if the patient is limited by comorbidities, 5 fx is a nice easy way to go.
I just got a pilot trial funded at my institution to do 30Gy/5fx adjuvant SBRT for APBI candidates, long term, we would like to do a pre-op SBRT trial, which of course would give us pCR rates.
I just got a pilot trial funded at my institution to do 30Gy/5fx adjuvant SBRT for APBI candidates, long term, we would like to do a pre-op SBRT trial, which of course would give us pCR rates.
I just got a pilot trial funded at my institution to do 30Gy/5fx adjuvant SBRT for APBI candidates, long term, we would like to do a pre-op SBRT trial, which of course would give us pCR rates.
Are you planning to give that dose in one week? Daily fractions?
I think Janet Horton from Duke has been doing this, pre-op, single fraction actually. I think she has more recent data since this time but here is her paper
Preoperative Single-Fraction Partial Breast Radiation Therapy: A Novel Phase 1, Dose-Escalation Protocol With Radiation Response Biomarkers. - PubMed - NCBI
I would imagine one would need to push higher that 30Gy/5 to get response rate > 10%.
Just some thoughts:Daily fractions. We want to let women be done in a week. Treated prone, with biozorb fiducials.
Perhaps, but not for healthy tissue.For neoadjuvant, agreed; for adjuvant 30Gy/5fx is basically same BED as Canadian without boost for alpha/beta of ~6Gy
Just some thoughts:
You may be overtreating them with this dose & fractionation.
39.9/2.66 in 3 weeks has been proven as adequate PBI in IMPORT low with almost no recurrent disease.
30 / 6 is more than 39.9 / 2.66 in terms of BED for healthy tissue, I'd be cautious. The British have published preliminary data on WBRT with 30 / 6 but with 1x/week fractions.
I'd be concerned about toxicity with 30 /6 in 1 week, remember the RTOG trial tried also to put all the dose in in one week and had not so good cosmetic results.
My guess: 25 /5 should be enough and better tolerated.
Perhaps, but not for healthy tissue.
START-B used a lower BED when they tried figuring out what dose to give instead of 50/2 and they were proven right with 39.9/2.66.
Plus, if you are giving all the dose in 1 week the linear-quadratic model is probably not the best to use with single doses of 6 Gy. The acceleration of treatmemt time is not been taken enough into account.
Horton is preop to the identified tumor. This 5 fraction / 30 Gy is adjuvant. I'd presume that you do different doses for preop/intact vs adjuvant? What's the rationale for preop by the way?
All good points, BED for normal breast is roughly 20% higher for this fraction, however, it must be considered that we are only treating the cavity (and a very precisely defined cavity by fiducials at the boundary) plus 1.5CM expansion (CTV and PTV) to that dose, the fall-off is very rapid because of a non-coplanar IMRT beam distribution. The amount of normal breast tissue receiving this dose is far lower than the amount of breast tissue getting between 100 and 107% in even a very well planned set of tangents.
Cosmesis results for the Timmerman phase II trial with this fractionation have been excellent, and our plans (hopefully) will be superior to his because his trial required greater expansions and had more cavity uncertainty. Additionally, our fiducials allow amplitude-based triggered imaging/treatment.
If I get a chance today, I'll post the results from my pre-clinical dosimetry.
Thought about it but clearly it will need conventional chemo before aggressive surgery and that chemo would likely need to be done locally....Not ideal, but if surgery and med-onc are completely abandoning her, then so be it. Multiple other co-morbidities to really justify complete lack of surgical intervention outside of just age and smoking?? If you disagree with surgeon assessment, can't hurt to send referral to local tertiary center for evaluation by (likely) more aggressive surgeons, after discussion with local surgeon of course given private practice environment.
Thank you for clarifying this. It's just that we have the negative experience with the RTOG0413-trial (which used an even higher dose that you are planning to within 1 week). Noone is using the RTOG-schedule anymore.
86 y/o smoker with a 3 cm ER+/H2N- breast CA with bx-proven LNs that have grown since bx after 2 months of AI therapy. Surgeon says she will "die" if she gets surgery and she smells like an ashtray. Lymph nodes are literally the size of oranges now, med onc has no interest in giving her neoadjuvant IV chemo.
Thinking of getting a PET/CT to confirm no distant mets and 63-66 Gy with Xeloda? Thoughts?
86 y/o smoker with a 3 cm ER+/H2N- breast CA with bx-proven LNs that have grown since bx after 2 months of AI therapy. Surgeon says she will "die" if she gets surgery and she smells like an ashtray. Lymph nodes are literally the size of oranges now, med onc has no interest in giving her neoadjuvant IV chemo.
Thinking of getting a PET/CT to confirm no distant mets and 63-66 Gy with Xeloda? Thoughts?