Radiation Oncology
Expert insights on radiation treatment planning, techniques, toxicity management, and multimodal cancer care.
Recent Discussions
How do you fractionate SBRT for NSCLC abutting the chest wall or in which the PTV encompasses part of the chest wall?
To reduce the incidence of chest wall pain, we typically treat lesions abutting chest wall to 70 Gy in 10 fractions. However, if the lesion is small (<3 cm), 50 Gy in 4 fractions can also be considered if we can meet the chest wall dose volume constraints (30 Gy < 30 CC ideally- if not, 30 Gy < 50 c...
How do you approach the treatment of de novo, brain-only metastatic HER2 positive breast cancer?
Patients who present with de novo, brain-only metastases of HER2+ breast cancer are rare, and hence, there is no good clinical experience or clinical trial basis upon which to base clinical practice recommendations. The current ASCO guidelines for the management of HER2+ brain metastases call for ap...
How do you counsel patients about prognosis with FIGO 2018 IIIC cervix cancer managed in the new era of chemoradiation plus immunotherapy?
The prognosis is still a function of nodal location, number of nodes, local T stage, histology, and response to the EBRT portion of treatment. The local control is closer to 90% with a predominant pattern of failure being distant (around 20-25%). Also based on A-18, 3 years PFS is around 70% and OS ...
How would you manage new symptomatic brain metastases (10-15) in a young woman with HER2+ metastatic breast cancer?
A lot of nuance to answering this on a per-patient basis.First question, how symptomatic? (As in, are there bulky mets that we should be considering surgical management upfront plus this also guides my discussion about whole brain vs systemic)If not acutely symptomatic and requiring a crani/resectio...
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...