Radiation Oncology
Expert insights on radiation treatment planning, techniques, toxicity management, and multimodal cancer care.
Recent Discussions
Are you altering your use of Active Breathing Coordination for breath hold technique patients in light of the COVID-19 pandemic?
We use DIBH, and this has not changed anything in our practice.
Would you ever consider stopping immunotherapy in a patient with metastatic melanoma after achieving a good response?
Yes, I would consider stopping immunotherapy in a patient with metastatic melanoma after achieving a good response.Data of 655 melanoma patients treated in pembrolizumab phase 1 KEYNOTE-001 study has shown 95 patients (14.5%) achieved CR after a median follow-up of 32 months. Treatment was discontin...
When do you consider it too late after lumpectomy to offer adjuvant whole breast radiotherapy?
I don't know if there are studies which have looked at this - to say there is no benefit at a certain time frame. Retrospective studies have shown higher local recurrence with delay of RT with variable time period in those studies (8 weeks to 20 weeks) . The most recent one from British Columbia loo...
Is there a time frame between surgery and radiation, after which, the benefit of adjuvant radiation is lost and no longer indicated for head and neck cancers?
Unfortunately, there are some patients that have post-operative delays. I don't know that the value of adjuvant RT "is lost" beyond 6-8 weeks, but we know the oncologic outcome can be worse. I would consider getting a high quality reassessment imaging either with CT, MRI and/or PET/CT of head and ne...
What is the role of adjuvant radiation therapy for stage III melanoma in the era of adjuvant Opdivo?
I think the role of adjuvant radiotherapy in stage III cutaneous melanoma is difficult to define at this time (June 2019). To be clear, the TROG trial mentioned above showed that adjuvant lymph node basin radiotherapy after therapeutic lymphadenectomy can decrease the chances of lymph node basin dis...
Can we use a linear accelerator to sterilize PPE?
Per FAQ's posted by ASTRO: "At this time, ASTRO does not recommend the use of clinical linear accelerators to sterilize PPE. While ionizing radiation is used for sterilization of blood and food products, this is achieved using industrial irradiators that use gamma irradiation at doses rates far grea...
Would you give PMRT to a young woman with a T1-2 breast cancer with a micromet on SLNB?
No great data as far as I know. In general, I treat micromets as ~pN0. @Dr. First Last and colleagues reported on LRR rates and prognostic factors for failure in pN0 patients treated with mastectomy to identify subsets of node-negative patients with sufficiently high risk of LRR who might benefit fr...
If you must start adjuvant radiation more than 6-8 weeks postoperatively, whether due to complications or healing, do you accelerate treatment in any way?
This is a controversial area with varied opinions. Here are a few of my takeaways: For delayed patients especially with high risk pathology, I usually re-image (preferably with PET) before making a recommendation. This is based on multiple series (Shintani et al., PMID 17889447, Kibe et al., PMID 3...
How long after surgery would you no longer offer adjuvant postoperative treatment for head and neck cancer when a patient (with multiple adverse features that needs adjuvant treatment) keeps postponing the start of radiation?
Ultimately, I feel this depends on why the patient keeps postponing treatment. If there are legitimate medical reasons for delay, I would not have a cutoff for starting adjuvant RT at any time - even several months after surgery - as long as the patient can tolerate curative-intent therapy and I hav...
How would you manage a multiply recurrent intramedullary pilocytic astrocytoma following re-resection?
For a conventional pilocytic astrocytoma, the Ki-67 index is typically <2–5%, with values above 10% being unusual. A recurrence with a MIB of 15% raises the possibility of a more biologically aggressive tumor, even if the histologic diagnosis remains pilocytic astrocytoma. As such, I would want to k...