Radiation Oncology
Expert insights on radiation treatment planning, techniques, toxicity management, and multimodal cancer care.
Recent Discussions
How do you approach patients with SMARCB1 deficient sinonasal carcinoma for immunotherapy?
Sinonasal cancers that are SMARCB1-deficient are rare. They tend to be more aggressive, present in more advanced stages, and tend to be associated with non-keratinizing histology. Despite this, there are no guidelines for a differential approach for these tumors and they are treated in a similar fas...
When treating high grade gliomas abutting critical structures, how do you balance tumor dose with critical structure constraints?
The CTV should be shaved away from critical structures if they are likely not to be involved with tumor. That said, expansion with PTV can put dose back into these critical structures and it may be hard to achieve full coverage without exceeding critical structure constraints. Although for PTV, we a...
Would you offer SBRT for a lung lesion adjacent to the heart in a patient receiving bevacizumab?
This question has lingered. Why is the patient on bevacizumab? Is the lesion biopsied and distinct histology? SBRT can be delivered in as few as 1 or 3 fractions, motion managed with no or mm margins. Hold the anti-VEGF a week before and after (no data). A biopsy helps define malignancy type and pot...
Would you ever consider repeating chemoradiation for patients with locally recurrent small cell lung cancer after prior chemoradiation for LS-SCLC?
I have re-treated in-field local recurrence SCLC advising thoracic radiotherapy first using SBRT dose and technique. Also, new lung cancers are more common in those who could not stop smoking.
When treating borderline resectable pancreatic adenocarcinoma patients with neoadjuvant chemoradiation, do you treat the elective nodal regions or the primary alone?
This is a very reasonable question without a clear answer, and I'd be interested in seeing how other people respond. As I've mentioned in a previous pancreatic cancer discussion on this forum, there are ongoing trials to evaluate whether radiation improves outcome in the resectable setting (RTOG 084...
Given improved BFS from the phase III FLAME trial, do you recommend focal SIB up to 95 Gy for unfavorable and high risk prostate patients?
As yet, I have not tried to dose escalate to that level using EBRT, preferring to use a brachytherapy boost if I feel patients might require more than I can safely deliver to the whole gland using IMRT. That said, however, I do not think that it would be wrong to try to deliver a focal boost using I...
What treatment fields do you use for N1mi breast cancer after lumpectomy/SLNB?
We treat with modified tangents including level 1 and 2 nodes in tangential beam for micrometastases. ER, PR, and her2 neu or oncotype does influence the decision for micrometastases after lumpectomy.
What is the appropriate target volume for SBRT to a non-vertebral osseous metastasis?
For non spine bone metastases, I usually treat the GTV with a 1 cm expansion of continguous bone to CTV + 0.3-0.5 cm margin in all dimensions to PTV. With this amount of contiguous bone, I will usually treat the entire circumference of the long bone. I rarely treat GTV + a small PTV expansion as ane...
When evaluating for PMRT in patients who did not receive neoadjuvant chemotherapy and are found to be pN0, do you utilize clinical T-staging, or pathologic T-staging?
If no neoadjuvant therapy, I rely on the pathologic staging rather than clinical staging for PMRT decisions. So, for a cT3 that is a pT1-2, I would not offer PMRT. I do consider factors including receptor status, margins status, LVSI, and age.
How do you assess whether an early-stage Hodgkin's patient is unfavorable?
I personally utilize the GHSG criteria for most patients. To review, a patient has "favorable" disease if they meet all of the following criteria: 1. 1-2 involved sites 2. No bulky disease 3. No extranodal disease (which is rare in early-stage HL) 4. Favorable ESR/B-symptoms profile (ESR < 30 with B...