Radiation Oncology
Expert insights on radiation treatment planning, techniques, toxicity management, and multimodal cancer care.
Recent Discussions
How would you treat laryngeal neuroendocrine carcinoma?
It would depend on extent and differentiation. If small cell, chemo RT. No point in surgery because they almost always develop distant metastasizes. If differentiated, it would depend on extent and surgical alternative.
Would you consider lymphovascular invasion at the margin to be a positive margin in breast cancer surgery?
LVI is an independent risk factor for local relapse despite adequate treatment. That being said, we don’t chase LVI to get negative margin as it is non contiguous involvement and not contiguous process which warrants any reexcision.
What brachial plexus dose constraints do you apply when treating conventionally fractionated NSCLC?
Yes. I am presuming you are discussing treating definitively with CRT for locally advanced NSCLC.Since RTOG 0617, most people that treat NSCLC prescribe to a dose of 60-66 Gy in 30-33 fx, as this is a feared toxicity that is very painful and decreases QOL. We try to keep the brachial plexus dose to ...
In what head and neck subsites, if any, would you recommend adjuvant radiation s/p high quality neck dissection if pN1 disease (single ipsilateral LN <3cm) was the only risk factor?
The societal guidelines are all over the place. I will consider PORT in pN1 patients without other pathological risk factors if the primary was oral cavity. Oral cavity primary is, itself, a risk factor for locoregional recurrence (Peters et al., IJROBP 1993). Various retrospective studies have sugg...
How do you approach hotspots/heterogeneity for palliative radiation plans?
For whole brain, hotspots are usually located superiorly, where the head narrows.Some options to reduce include: higher energy/mixed beams and supplementing the laterals with field in fields to keep the hotspots lower than 110%. Mixed energy plans look very nice, but consider contouring a brain CTV ...
For a patient otherwise suitable for APBI, would neoadjuvant endocrine therapy administered for extemporizing reasons (e.g., COVID diagnosis and recovery, rather than downstaging) preclude consideration of APBI?
I have not typically treated patients with APBI if undergoing neoadjuvant therapy (chemotherapy or endocrine therapy). In theory, if endocrine therapy was a short amount of time, PBI could be considered but I have favored HWBI in these situations.
When would you include the superior mediastinal lymph nodes when treating head & neck cancer and how do you define the target volume?
Low level 4 and/or 6 nodes.
How do you approach H&N radiation in a patient who recently had carotid endarterectomy (cancer incidentally found during surgery)?
I’m guessing in a lymph node. It would depend on the location. External jugular think skin. Internal jugular think mucosa. Close, heal, work up for unknown primary. CT and PET. Check path for HPV. Treatment depends on whether it’s likely a mucosal vs skin primary.
In what situations do you utilize motion management of the optic structures?
A paper published in Br J Radiol. 2019 (Xiang et al., PMID 31067077) showed, based on MRI, an average physiological motion of the optic chiasm to be 0.5-0.75mm. We have used at least 1mm expansion of the optic nerves and chiasm in our stereotactic radiosurgery treatment planning.
Would you consider definitive RT in a patient with oligometastatic bladder cancer who is not a surgical or chemotherapy candidate?
Oligometastatic bladder cancer has quite a poor prognosis and most local treatment in this setting is palliative in nature. Durable local control that provides hemostasis and prevents obstruction and other urinary issues is crucial. 30/10, 40/15, 55/20 are all potential options, but knowing that thi...