Radiation Oncology
Expert insights on radiation treatment planning, techniques, toxicity management, and multimodal cancer care.
Recent Discussions
How would you treat pelvic node recurrence after prior RP and adjuvant XRT prostate bed only?
RT to pelvic nodes to aortic bifurcation, boost positive nodes, plus ADT.
In what situations would you routinely offer 25 Gy/5 fx for glioblastoma?
We use this regimen in two situations, based on clinical need. Ultra short course in very poor performers unwilling for more elaborate treatment and needing very short term palliation. Recurrent GBM's, not resectable but reasonable targets for SRS, but too large for single session 15-17Gy in one se...
What is your approach for LINAC based radiosurgery when dealing with benign perioptic lesions very close to the optics apparatus?
It all starts with the consideration of what I consider an effective dose of SRS or SRT (hypo-fractionated SRS). The minimum effective dose to achieve local control of a metastatic lesion is usually 18 Gy for single fraction, 27 Gy for 3 fractions, and 30 Gy in 5 fractions.I then consider the histol...
How would you manage a metastatic lesion abutting the optic structures (globe, optic nerve, etc)?
Generally, if I'm treating a metastatic lesion abutting an OAR - in this case, it's an optic nerve - I try to keep my Dmax to the optic nerve/chiasm to 8 Gy (allow up to 10 Gy if needed). If I can't achieve those constraints, I would favor fractionated radiosurgery. There are some papers looking at ...
In the setting of single or multi-fraction cranial radiosurgery, do you have different constraints for the dose to the optic tract just posterior to the chiasm, compared to the constraints for the chiasm?
I treat the post-chiasmatic tract the same as the pre-chiasmatic nerve segments in a single x-shaped structure. As for the optic striations, as they blend into the brain, they get treated the same as the rest of the brain.
Would you treat T1a glottic cancer with single vocal cord irradiation using IGRT?
Treating glottis larynx ca with IMRT/VMAT sparing the carotid artery has been reported by several institutions and is straightforward (for example, here). The benefits are supposed to be reduced cerebrovascular events, however, the utility of this approach is unknown, taking into account the relativ...
Do you prescribe silvadene cream for patients with a sulfa allergy?
No. I will consider hydrogel wound dressings in those situations
What is your preferred method for adding bolus, at CT sim or virtual bolus?
Absolutely, should always apply at sim. Gives you an opportunity to work out the appropriate positioning of the patient to optimize bolus conformality and to select the appropriate bolus type (frequently Superflab but often you don’t know until you get the patient on the sim table whether custom mol...
Is ENI necessary for postoperative treatment of clinically N0 adenoid cystic carcinoma of the head and neck?
Adenoid cystic carcinoma (ACC) is an uncommon malignancy of the head and neck characterized by an intermediate growth rate and a propensity for local recurrence, perineural tumor spread, and distant metastasis. Historically thought to be radioresistant, patients were treated with surgery alone until...
Is it ever appropriate to omit temozolomide in unmethylated glioblastoma?
Perhaps a different perspective on this question would be which unmethylated patients would you be willing to not treat with up-front temozolomide? The genesis of the question and conundrum comes from the modest benefit described in the above-mentioned trials for this subgroup. As Hegi herself descr...