Radiation Oncology
Expert insights on radiation treatment planning, techniques, toxicity management, and multimodal cancer care.
Recent Discussions
How do you approach SBRT liver constraints when the total liver volume is <700 cc?
We consider 3 different methods of thinking about liver constraints when evaluating a plan: 1) Sparing 700 cc's to < 15 Gy (for 3 fractions), and <17 Gy (for 5 fractions). 2) Liver mean dose constraints (as in RTOG 1112 for CP A cirrhosis, <14 Gy), and <15-16 Gy for non-cirrhotic patients depending ...
Should high risk prostate cancer patients be placed on more potent ADT (abiraterone or enzalutamide) in the upfront setting with definitive RT instead of the standard LHRH agonist?
With STAMPEDE suggesting improvement with the addition of abiraterone in very high risk N0 patients, this is certainly becoming a consideration. Duke is completing a trial of concurrent abiraterone/STADT/definitive radiation for intermediate and lower high risk prostate cancer. Results forthcoming. ...
What are reasonable SBRT dose constraints for the lumbosacral plexus?
There are published dose tolerance guidelines for the sacral plexus with the AAPM TG101 report Benedict et al. Med. Phys 37(8): 4078-4101, 2010. Realize these have not been validatedOn page 4086, there is a table with suggested dose constraints for a 3 fraction regimen that include a threshold dose ...
For patients undergoing bladder preservation therapy with trimodal therapy, how do you manage the urinary urgency and frequency during and after treatment?
This can be a difficult problem to manage because I try to avoid treatment interruption if at all possible, which is different from my approach in patients with prostate cancer, where treatment interruption is a safe and effective alternative. In patients with bladder cancer, the first thing I will ...
How do you approach liver SBRT in patients with hepatocellular carcinoma who aren't candidates for surgery or other interventional procedures when the overall liver volume is small making it difficult to achieve liver constraints?
These are tough situations. I have used proton and photons for HCC. In the situation you described, I would generally favor IMPT due to improved low dose distribution and keeping the parenchyma not treated to a minimum while still giving an ablative dose more comfortably. Although the mean liver dos...
What neoadjuvant approach is best for an adenocarcinoma of the GE junction (arising in Barrett's) with a large hiatal hernia?
I haven't found any publication or clinical trial regarding this very incidental finding. However, I had the opportunity of discussing in tumor board a similar case. I suggested to consider surgical management of the hiatal hernia first, and shortly after recovering, proceed with chemotherapy and ra...
If a patient diagnosed with seminoma after orchiectomy has margin positive disease noted in the spermatic cord and no overt metastasis on imaging and normal tumor markers, how should this patient be staged?
I believe that the staging would be pT3cN0M0S0 in this case. Margin-positive disease suggests continuous rather than discontinuous spermatic cord invasion. In case this was felt to be discontinuous, NCCN v1.2024 now has a note on staging such patients as pT3 (high-risk stage I) and not as M1 (stage ...
Do you prefer to treat patients prone (on a belly board) or supine when treating rectal cancers?
If the goal is reducing small bowel dose, one should use a belly board and treat in prone position. There was a systematic review in the Green Journal regarding this. It's also beneficial when treating with IMRT, as seen in this publication.
How would you manage an epidural spinal metastasis causing cord compression from rhabdomyosarcoma?
Leptomeningeal spread of rhabdomyosarcoma could result from the dissemination of tumor cells in the CSF by direct extension or by malignant cells growing along blood vessels or nerve sheaths. I would first get a total spine and a brain MRI to assess where there is gross disease present in other part...
Would you recommend adjuvant radiation for a large dedifferentiated anterior abdominal wall liposarcoma?
When I have the opportunity to evaluate such a patient before treatment begins, I strongly favor pre-operative radiation with conventional fractionation and margins. If meeting the patient after surgery, it depends a great deal on how the closure was accomplished: reconstructed abdominal wall, prima...