Radiation Oncology
Expert insights on radiation treatment planning, techniques, toxicity management, and multimodal cancer care.
Recent Discussions
Based on the recent guidelines, should prostate SBRT dose be no higher than 3625 cGy in 5 fractions?
We have delivered prostate SBRT in high volume using 3,800 cGy/4 fx since 2006. The UCSF group has also used this schedule in a large number of patients for a similar time frame. For over a decade prior to that, the exact same dose regimen was used with HDR brachytherapy and published as "safe and e...
How do you approach treatment for a patient with an isolated perineal/pubic recurrence of penile SCC s/p definitive surgery?
This would be a case where multidisciplinary input would be very valuable including input from surgery, medical oncology, and radiology. An MRI may also be helpful to help better define the local extent of disease for the multidisciplinary evaluation, and I would try to get a PET/CT to aid in the as...
Do you restrict the dose rate during treatment delivery to a pacemaker in addition to limiting the Dmax?
Delivering a high dose rate implies that the pacemaker would be exposed to the machine's direct output. High-dose-rate exposure to a pacemaker could lead to an instantaneous malfunction and, even if temporary, should be avoided. Please err on the safe side.
Would you treat a patient for heterotopic ossification prophylaxis if >72 hours after surgery?
RT is very effective in reducing heterotopic ossification that can happen after surgery/trauma to the hips. We have always been taught to do either before 24 or less before surgery or within 72 hours after surgery. The rationale is that RT prevents HO by the inhibition of osteoprogenitor cells proli...
How do you manage bladder spasms during pelvic radiotherapy?
My approach would depend on the disease under treatment, specific symptoms, concurrent therapies, and whether or not the patient has a prostate. The first thing I would do, if you have not already done it, is obtain a urine sample to rule out infection. Let's assume that was done and there is no inf...
In locally advanced rectal cancer treated with total neoadjuvant therapy, do you adjust boost volumes to only include post-chemo gross disease/nodes plus a margin?
The answer to this question is that there is usually no risk reduction advantage to making the boost volume smaller for the last 5.4Gy. it may be better to make the boost volumes larger than a uniform expansion on the GTV.There is no definitive guide to boost volumes in rectal cancer. We published o...
What is the recommended approach for a 7 cm x 5 cm paraspinal subcutaneous desmoid tumor (T6 to T9) incidentally detected on PET CT during NSCLC monitoring, with confirmed growth over 18 months?
Medical management is the preferred treatment for patients with desmoid tumors when the DT either causes symptoms (pain, deformity) or has confirmed growth by RECIST criteria over at least 6 months. If this patient has a DT that is worsening over 18 months and threatens the integrity of the spine, t...
Would you treat with consolidative SBRT for oligometastatic liver mets from HER2+ breast cancer if these lesions demonstrated radiographic CR/near-CR following neoadjuvant TCHP chemotherapy (and patient is receiving ongoing adjuvant HP therapy)?
I would not if radiographic CR or near CR. If there any suspicions of residual disease vs. scar, favor surgery, which will establish diagnosis and also take care of oligomets.
Do you ever treat patients with rectal or anal cancer with IMRT in the prone position?
I would favor treating most patients with rectal and anal cancer in the prone position, with a bowel exclusion device incorporated into the immobilization. The RTOG 0529 small bowel DVH data suggest that, even with IMRT, there is at least a trend favoring the prone position. In my own practice, the ...
Do you recommend resection for positive anterior or posterior margins in a patient s/p mastectomy if the surgeon says they took all the breast tissue anteriorly to the skin or posteriorly to the fascia?
It's hard to localize a margin positive area after mastectomy (unlike lumpectomy) and most of the time we dont recommend resection unless the area can be localized with certainty