Radiation Oncology
Expert insights on radiation treatment planning, techniques, toxicity management, and multimodal cancer care.
Recent Discussions
Would you use a hippocampal sparing technique when treating with PCI for a limited stage small cell lung cancer?
This is an important question where the evidence is evolving, and some key trials remain ongoing. Because the data remains in flux, in the ongoing phase 3 SWOG S1827/Maverick trial of MRI surveillance +/- prophylactic cranial irradiation (PCI) for LS and ES-SCLC, where I serve as the PI, hippocampal...
Are there select patients with rectal cancer where radiation field size reduction might be feasible?
Yes, however, how to select which patients could have a field size reduction is unknown. Such a field size reduction is probably even more acceptable in the era of total neoadjuvant therapy, however, this cannot be considered standard of care given the absence of trials evaluating such novel approac...
Are there any volumetric constraints associated with toxicity in the dose range that is moderately above prescription (i.e. 30-35 Gy range), when planning hippocampal-sparing whole brain radiation?
This is an important question worth some discussion. As the question mentions, clinical trials of HA-WBRT have permitted a hot spot of 133% of the prescription dose of 30 Gy (or 40 Gy) to D2% of the whole-brain parenchyma as an acceptable protocol variation. Importantly, none of these trials have de...
Do you constrain the dose to the oropharynx, parotids, or oral cavity when planning HA-WBRT?
On NRG CC001, there was no inter-arm difference in reported adverse events of oral mucositis (N=6 on conventional WBRT arm vs. N=4 on HA-WBRT arm), oral pain (N=3 on conventional WBRT arm vs. N=1 on HA-WBRT arm ), or dry mouth (N=19 on conventional WBRT arm vs. N=18 on HA-WBRT arm) (Brown et al., PM...
Do you use either memantine or hippocampal sparing technique to preserve cognitive function when giving whole brain radiotherapy?
Dr. @Dr. First Last and I put together the response below:We use memantine and hippocampal sparing technique for all brain metastasis patients who are planning to receive WBRT. This is based off the recently published phase III trial NRG CC001 that found hippocampal avoidance WBRT plus memantine res...
Is there a correlation between rectal cancer stage and dose response to radiotherapy?
Possibly. While some compelling data from Appelt et al. in 2013 reflected there may be a correlation between RT dose and rectal tumor response (Appelt et al., PMID 22763027), an extensive number of prospective trials examining the influence of boost doses of RT on pathologic response have produced m...
Can we use a linear accelerator to sterilize PPE?
Per FAQ's posted by ASTRO: "At this time, ASTRO does not recommend the use of clinical linear accelerators to sterilize PPE. While ionizing radiation is used for sterilization of blood and food products, this is achieved using industrial irradiators that use gamma irradiation at doses rates far grea...
Would you offer hippocampal sparing whole brain radiation for patients with brain metastases due to ES-SCLC?
Until we have built-in auto-segmentation, I find the RTOG contouring atlas very helpful for manual contouring of the hippocampus. I tend to use the lateral ventricle as my main landmark, and look for the circle of gray matter located medial to it. Once I've drawn a hippocampus, I'll look at it in th...
Are CHEK2 mutations a contraindication for breast conservation therapy with lumpectomy + RT?
Among women with early-stage breast cancer and moderate penetrance breast cancer susceptibility genes, such as CHEK2, decisions about breast surgery are largely based upon personal preferences. According to data from large population-based studies, women with CHEK2 pathogenic variants have about a 2...
How do you manage moist desquamation when treating vulvar cancer?
My experience is largely limited to the treatment of gynecologic malignancies, with the treatment of vulvar lesions the most common reason for development of moist desquamation. The first goal, in my opinion, is to prevent development of moist desquamation as much as possible. Skin folds that are no...