Do you have a maximum size cutoff for lung SBRT in central NSCLC?
E.g. for a 7cm central NSCLC, would you offer 8 fx SBRT or ChemoRT? Patient is not a surgical candidate.
Answer from: Radiation Oncologist at Academic Institution
The bigger the tumor size, the lower the efficacy of SBRT. Typically, I wouldn’t treat lesion of size >7 cm for the following reasons:
The local control is lower even with BED>100 Gy;
There is high chance that the PTV overlaps with critical structures so toxicities could be high.
Th...
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Radiation Oncologist at Gulf International Cancer Center Helpful guideline to follow.
Answer from: Radiation Oncologist at Academic Institution
This question regarding appropriateness for lung SBRT has many components which I will break down one at a time. Regarding tumor sizes 5 cm and greater, we are comfortable offering a lung SBRT approach. As long as the OAR constraints we standardly use for our smaller tumors are met, then we feel com...
Answer from: Radiation Oncologist at Community Practice
Technically, large T3 lesions (up to 7cm) were included in the protocols and studies, however, their numbers weren't well represented.
Anything above 7 cm would be a T4 lesion and I would favor chemorads followed by a year of imfinzi if the patient is eligible.
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Medical Oncologist at Arizona Hem/Onc Maybe it's time we do Circulating tumor DNA in tum...
Answer from: Radiation Oncologist at Academic Institution
This is an interesting question which I have been addressing. As many may know, during our phase I dose escalation study in Indiana in the early 2000's we had two separate escalation strata, one being for tumours >3 cm and reached a dose of 2400cGy X 3 fractions (7200cGy total) without inhomogene...
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Radiation Oncologist at Pikeville Medical Center So looking forward to hearing more about this!
Answer from: Radiation Oncologist at Academic Institution
I do not have a maximum size cutoff for SBRT for either peripheral or central SBRT. My decision on using SBRT is based predominantly on whether I can meet safe dose constraints. This often becomes challenging for tumors >5-7 cm, depending on tumor location and patient anatomy/lung volume. Once I ...
Answer from: Radiation Oncologist at Academic Institution
To me, it’s an issue of dosimetry. If you can achieve dose constraints, you’re fine with any size tumor. It’s certainly more difficult as they get bigger and I am more likely to use an 8 or 10 fraction course.
Helpful guideline to follow.