Radiation Oncology
Expert insights on radiation treatment planning, techniques, toxicity management, and multimodal cancer care.
Recent Discussions
What dose constraint do you use for the female urethra in gynecologic brachytherapy?
In our experience the tolerance is very different as the prostatic urethra and membranous urethra are very different. We have published our limited experience in Brachytherapy. When we do interstitial HDR brachy we limit 0.1 cc to 100 percent or less of what we prescribed. The 2cc concept is not app...
What dose do you use in the adjuvant treatment of desmoid tumors?
The dose range in retrospective data is between 50-60 Gy, with no dose response beyond 60 Gy even for gross disease treated with RT.
Is it acceptable to treat pediatric Hodgkin's lymphoma with an involved nodal field outside the setting of a clinical trial?
It probably is. Although not proven by randomized trial/s in pediatric patients, the practice is accepted in adults. In children where long term morbidity of radiation therapy is of greater concern, it would not be unreasonable to use involved nodal field in combination with chemotherapy.
Is it feasible to treat craniospinal fields with new generation scanning beam-only proton machines?
Yes, it is feasible to treat craniospinal fields with scanning beam-only technology. Scanning beam proton therapy delivers one discrete Bragg peak "spot" at a time. Large fields require many spots; so treating large fields such as craniospinal fields with scanning beam techniques requires more time ...
Is it preferable to simulate pediatric Hodgkin's lymphoma patients with arms up or akimbo?
We will be moving towards involved site radiotherapy for pediatric Hodgkin lymphoma. Consequently, you may want to match the simulation with the set up of their pre-treatment PET/CT scan (arms up vs arms down). This will allow you to have more certainty regarding the location of axiallary and subpec...
Is it safe to re-irradiate the pelvis after definitive prostate brachytherapy?
Evaluating the brachytherapy dosimetery can be very useful here. It will provide a visual reminder of how conformal such tx can be. The bladder was likely not exposed. Next, if brachytherapy planning software is available, the doses could be reconstructed and superimposed on the new CT sim (if impla...
What is the likelihood of a successful pregnancy following pelvic irradiation?
This is a very important question. The risks on future fertiltiy from radiation therapy to the abdomen/pelvis are twofold.1) Dose to the ovaries. The LD-50 to the ovaries may be as low as 2 Gy, thus the risk of ovarian dysfunction and premature menopause, is high. 2) Dose to the uterus leading to po...
Do HIV/AIDS patients with prostate cancer have increased radiation toxicity?
This small study suggest that outcomes are the same for HIV vs. non-HIV patients. That's also been my general experience.Matched cohort analysis of outcomes of definitive radiotherapy for prostate cancer in human immunodeficiency virus-positive patients. (Kahn S, Jani A, Edelman S, Rossi P, Godette ...
What is the difference between involved node and involved site irradiation?
In both involved node and involved site (ISRT), prechemotherapy GTV determines the CTV. However, ISRT accommodates cases in which optimal prechemotherapy imaging is not available to the radiation oncologist. In ISRT, clinical judgment in conjunction with the best available imaging is used to contour...
Is it time to start incorporating involved site irradiation for all lymphomas?
Involved site radiation is becoming the new standard therapy for lymphomas and the goal is to incorporate the ISRT concept broadly. ISRT evolved to update field design guidelines to take into account 3D imaging rather than base field design on bony anatomy which is the way we designed fields in the ...