Radiation Oncology
Expert insights on radiation treatment planning, techniques, toxicity management, and multimodal cancer care.
Recent Discussions
How do you approach an out of field intracranial recurrence for a GBM?
Any patient with recurrent GBM should have multidisciplinary evaluation for indivdualized clinical decision. For patients with out of field recurrence, I would still consider clinical trials as the first option. Off trial, multiple factors should be taken into consideration, including, age, KPS, ne...
When treating keloids with electrons post-operatively, what margin do you use when making your electron field cut out?
Usually about 1 cm around the scar on each side to account for penumbra which is 10% of energy of electron (6 mm for 6 mev electron) and small set up uncertainty.
If an anatomical defect forms due to rapid disease response from pelvic radiation for large gynecological tumors, is it safe to proceed with a further radiotherapy boost?
I would proceed with brachytherapy as planned. For a fistula, if symptomatic, would consider diversion - bilateral nephrostomy or diversion colostomy as needed. Brachytherapy would treat the involved bladder or rectal wall to a therapeutic dose without any needles in the tissue, thereby avoiding any...
Given POP-RT trial, do you cover elective nodes in high risk prostate cancer?
Ah, to treat nodes or not for prostate cancer -- an area that everyone loves to debate. The recent, fascinating POP-RT trial does shed some important light on this topic, but it's important to keep the trial's patient population in mind when deciding whom to apply it to. Also, the trial is not witho...
Why is there a benefit of ADT for high risk prostate cancer treated with radiation, yet no large trials describing benefit of adjuvant ADT after radical prostatectomy?
From a high level, the magnitude of the benefit of ADT with radiation seems proportional to the aggressiveness of the disease (i.e. low risk has no significant benefit, int risk weighs risk features and cardiac health, and high risk the benefit of ADT can trump cardiac risk). In that context, we hav...
What CTV margin do you use for IDH-mutant WHO grade 3 or 4 astrocytoma?
IDH-mutant (IDHm) WHO grade 3 or 4 astrocytomas carry a better prognosis than their IDH-wild type (IDH-wt) counterparts. These patients tend to live significantly longer than the IDH-wt. Current NRG consensus guidelines call for a 2 cm expansion over the GTV1 (T2/Flair) and GTV2 (cavity and any resi...
What SBRT dose and constraints would you use for a primary endobronchial NSCLC that is too thick for brachytherapy?
It really depends on the size and location of the lesion with respect to the proximal bronchial tree and other mediastinal structures (such as the esophagus). SBRT, as commonly understood (e.g., 50 Gy in 5 fractions), strikes me as risky in most such scenarios. Something more like 60 Gy in 15 fracti...
If a stage I laryngeal cancer completely responds to FU-based chemotherapy (given for another malignancy) would you consider observation?
We expect a 60-80% response rate with induction chemo data, with 20% having a complete response. That doesn’t preclude local treatment but predicts for better outcome.
Does non-urothelial histology impact your approach to chemoradiotherapy for muscle-invasive bladder cancer?
There is no randomized data available in this regard to guide us through non-urothelial histologies for MIBC. However, certain points that are worth considering in their management are: For small cell or neuroendocrine tumors, cisplatin/etoposide or ifosfamide/doxorubicin-based systemic therapy in ...
Does the presence of cribiform histology at biopsy in prostate cancer affect your management in an otherwise intermediate-risk prostate cancer?
There have been no trials on this specific question, so there is room for debate and more science (hoping our recent grant submission in this area gets funded...). Here is my current thinking. This is for generally healthy patients with long life expectancy (≥10 years, but especially if ≥15 years). ...