Radiation Oncology
Expert insights on radiation treatment planning, techniques, toxicity management, and multimodal cancer care.
Recent Discussions
How would you manage a pre-menopausal woman with extranodal marginal zone lymphoma confined to the bladder wall?
Marginal Zone Lymphoma (MZL) when localized is curable in most instances with modest doses of RT (24-30 Gy), perhaps even less when the primary site is the orbit. It typically responds to rituximab but relapses occur in most cases. Therefore, definitive RT is the treatment of choice in the great maj...
For primary MZL of the breast, do you do whole breast to 24 Gy or ISRT?
Without knowledge of the age of this patient and whether the concern of carcinogenicity from half the normal dose of traditional whole breast radiation (which we obviously do all the time for breast cancer) is enough to warrant omission of curative intent therapy in what is otherwise described as a ...
Would you consider 5-fraction whole breast RT for a patient with multiple positive margins following lumpectomy for whom reexcision is not possible?
It’s not the whole-breast fractionation that matters, as 5 or 15 fractions are adequate doses for whole breast, but I would definitely add a boost equivalent to a dose of 16 Gy to the surgical bed.
What dose constraints do you use for 15-25 fraction hypofractionated RT for cholangiocarcinoma?
5Fx 10fx 15fx 25fx Ablative dose 50Gy 60Gy 67.5Gy 75Gy GI tract pt dose (0.2cc) 30Gy 40Gy 45Gy 60Gy Bile Duct pt dose (0.2cc) 40Gy 65Gy 70Gy 80Gy Liver – GTV Mean dose + 700cc below + 1/3 liver over 15Gy 20Gy 24Gy 28Gy Mean dose CP...
When using FAST Forward, how important is it for the treatment to be delivered Monday through Friday in one week as opposed to spanning a weekend?
Presumably unimportant. From the protocol: "13. TREATMENT SCHEDULING AND GAPSTreatment can start on any day of the week.A gap of up to 3 days is acceptable in the event of machine service or breakdown. This is preferable to transferring the patient to a machine on which daily verification imaging is...
How do you manage an unresectable high-grade glioma of the distal cord/cauda equina?
Doses may vary by institution. Our typically practice is to cover the gross disease to 54 to 50.4 Gy in 1.8’s for conus/cauda and then approximately two vertebral bodies above and below to 50.4-45 Gy (for instance if the superior extent is in true cord, then it’s typically prescribed to 45 Gy with p...
Do you recommend adjustment of lung dose constraints in the setting of stage III lung cancer treated with definitive concurrent chemoradiation followed by planned consolidation immunotherapy?
No, the normal tissue constraints have not changed now that adjuvant durvalumab is the new standard of care. Of course we should always be trying to make our normal tissue dose constraints as low as possible, without underdosing the target. And we should probably assume that all patients are going t...
How do you create an ITV for liver SBRT (metastatic lesions) when you don't have a 4D-CT or fiducials?
I will add a comment about ITV generation. Even with abdominal compression, there can still be movement of 8-10 mm or more depending on the abdominal compression system, body habitus of the patient, and breathing pattern. Fusing the MR and PET-CT only helps you delineate a GTV but it does not addres...
What is your IGRT motion management approach for liver SBRT?
For liver SBRT, there are a number of ways to address IGRT. All patients should have been simulated with either a 4DCT scan (can consider 4DCT with a compression belt) to generate an ITV or motion management or most ideally, a breath hold technique to maximally limit tumor/liver motion. Trying to re...
Is it feasible to use MV fluoroscopy to monitor the treatment port for left-sided breast cancer with DIBH?
Absolutely. When we first started doing DIBH, I used to stand at the machine with the MV fluoro on to watch the treatment. It was indeed very reassuring. As I recall, I was able to see the beating heart beneath the block, or maybe was just able to see the edge of the beating heart at the field edge....