Radiation Oncology
Expert insights on radiation treatment planning, techniques, toxicity management, and multimodal cancer care.
Recent Discussions
What dose-fractionation scheme and esophageal constraints should be used to treat an ultra-central, medically inoperable, stage I NSCLC abutting the esophagus?
For lesions abutting the esophagus, SBRT with BED >100 Gy should NOT be used due to high risk for ulceration and even fistula. Instead of SBRT, more fractionated radiotherapy with BED <84 Gy should be considered (60 Gy in 15 FX is still too high for the esophagus). In addition to maximal point dose,...
When contouring locally advanced NSCLC, how do you define your ITV if your iGTV overlaps with an OAR?
For locally advanced lung, I have 2 slightly different approaches for primary vs nodes. For primary, GTV to iGTV (with 4DCT or DIBH scans x 3 at sim in certain cases) to CTV (5 mm expansion cropped to anatomical barriers to spread) to PTV (5 mm uniform expansion). I let the iGTV overlap the esophagu...
Do you treat inguinal lymph nodes for rectal cancers involving the anal canal?
One of my residents recently told me that I should treat the inguinal nodes for low lying rectal cancers based on recommendations on the MedNet. I realized this is an old post, but I would like to add a nice reference that really convinced me that there is probably minimal benefit to treating inguin...
When do you consider it too late after lumpectomy to offer adjuvant whole breast radiotherapy?
The phrase, "The perfect is the enemy of the good" comes to mind...This is always a tough situation, but not uncommon in the "real world", especially with underserved patients. You hope that someone was proactive enough to place the patient on hormonal therapy if such a delay was anticipated. There ...
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...
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...
Would you include draining lymphatics as part of an adjuvant radiotherapy course following gross total resection of sinonasal sarcoma?
No.
What is your approach to radiographically suspicious lung nodules for which initial biopsy was negative for malignancy?
It depends on how suspicious the nodule is for malignancy clinically and on the biopsy. The following criteria play into my decision-making: If the kinetics (steady growth over multiple scans) and morphology (solid and spiculated) on CT as well as hypermetabolism on PET-CT are highly suggestive of ...