Radiation Oncology
Expert insights on radiation treatment planning, techniques, toxicity management, and multimodal cancer care.
Recent Discussions
What SBRT dose would you give to a single external iliac lymph node recurrence (1 cm size) for a patient previously treated with salvage radiation to the pelvis?
35 Gy/5 is fairly safe in the re-irradiation setting, and in our experience, it's quite effective for nodal disease.
When do you recommend post-operative radiation therapy for extracranial chondrosarcoma?
When an en bloc resection with negative surgical margins is not achieved. Typically, this means tumors of the axial rather than appendicular skeleton, as margins are typically wide in the latter. There is "oncolore" that chondrosarcomas are radioresistant tumors. This is likely true at lower pallia...
Do you typically incorporate radiotherapy into the management of extraskeletal myxoid chondrosarcoma?
Yes. RT appears to be quite effective in improving LC for chondrosarcomas, including extraskeletal myxoids. This is likely to be particularly relevant where wide margins cannot be obtained (e.g., spine, pelvis, joints).The benefit of RT (HR 0.27 for LF) was nicely shown in a recent large, well-condu...
In light of Aizer et al. data presented at ASCO 2025, what is your threshold for offering SRS/SRT in patients with multiple brain metastases?
Over the past 4 decades, the treatment of brain metastases has been evolving along with advances in technology, from simple whole brain radiation (WBRT) with opposed lateral fields to IMRT-driven treatment (HA-WBRT); similarly, in the field of SRS/SRT, we have pushed the envelope of what we can achi...
When evaluating margin status to consider APBI for early stage invasive breast cancer, given the specification for at least 2 mm margins, do you look at the DCIS margin or only the invasive margin?
I take a slightly different approach. Current guidelines for breast conserving surgery allow for no tumor on ink for invasive cancers, even those with DCIS associated. While ASTRO guidelines recommend 2 mm for APBI (Correa et al., PMID 27866865), other guidelines such as the ABS do not for invasive ...
How does a close DCIS margin factor into surgical and radiation decision making for Stage I invasive ductal carcinoma after breast conserving surgery?
Based on SSO and ASTRO guidelines for invasive tumor, no tumor at inked margin is considered negative by us for suitability for adjuvant RT. If there was calcification as part of the mammographic finding, then for close DCIS we would look at the specimen radiograph and also consider pre-RT mammogra...
How long would you stop standard GBM radiotherapy if the patient had a fall with minor head trauma?
I would do everything possible to minimize or ideally avoid treatment breaks, given no intracranial bleed. I would evaluate skin dose over the area of laceration and consider adapting the plan to meet skin constraints or lower dose to the suture if possible and not already low. If significant swelli...
In what situations do you recommend adjuvant radiotherapy for colon cancer?
It is appropriate to be cautious when considering the use of CXRT in patients with resected colon cancer. The main reason is that in the post-operative setting there is almost always fixed small bowel adherent to the tumor bed. For this reason, one may not be able to deliver a high enough dose to pr...
How do you approach management of a patient with intermediate risk prostate cancer treated upfront with HIFU and intermittent ADT who is later found to have rising PSA and biopsy-proven prostate-confined recurrence?
These are frustrating situations, and ones I am now seeing frequently as focal therapies have gained traction in the United States. The approach, needless to say, is highly individualized. Often, these glands are quite abnormal in MRI appearance, and there is a concern for fibrosis. My approach is h...
What is your approach to patients with locally recurrent prostate cancer following cryotherapy or HIFU?
Limited data has been published on this subject, however, the best results from a standpoint of disease control and side effect profile have been observed with salvage radiotherapy. In general, our practice has been to treat these patients with definitive radiation to doses of 70-74 Gy. For patients...