Radiation Oncology
Expert insights on radiation treatment planning, techniques, toxicity management, and multimodal cancer care.
Recent Discussions
Can pre-op chemoRT be used to potentially downstage an early stage rectal cancer (i.e. T2 N0) for a sphincter sparing operation?
It is certainly appropriate to consider pre-operative chemoRT in an early stage rectal cancer that would not otherwise require neoadjuvant chemoradiation.The goal here would be to convert the operation from one resulting in a permanent ostomy (APR) to one allowing sphincter sparing (LAR). Good data ...
What is your typical target/field when treating a patient with 5 Gy x 5 fractions pre-operatively for rectal cancer?
The European experience with short course preoperative radiotherapy uses treatment portals that are somewhat smaller than what many of us utilize in the US. At Washington University we have a long experience (that pre-dates the Swedish trials) with 4Gy X 5fx for readily resectable tumors. The cases ...
Would you offer additional radiation therapy in a medically inoperable patient with rectal adenocarcinoma who has a persistently palpable tumor after definitive chemoradiation therapy?
I recently was writing up some data about pCR after SBRT for lung and it still seems a bit of a surprise to folks that pCR rates increase over time after XRT. The velocity of this change over time is almost certainly related to histology and other factors like tumor doubling time. It's all about the...
Is there a role for unilateral hippocampal sparing?
There is some lateralization of hippocampus function which may impact decision making.The left hippocampus seems to play more of a role in episodic verbal memory, while the right plays more of a role in spatial processing. Our neurosurgeon has told me before that a left hippocampectomy is much worse...
Do you give post-operative radiation to Ewing sarcoma if there is poor histologic response to neoadjuvant therapy in a completely resected tumor?
US Ewing studies conducted through COG have used histologic response in more recent protocols to play a key role in how margins are assessed, such that patients with >90% necrosis and inflammatory or coagulative necrosis at the margin require RT, while those with bland scar or fibrous tissue do not....
What is your follow up schedule after completion of RT for pediatric rhabdomyosarcoma?
Imaging surveillance is an interesting and yet complicated issue. If a child is enrolled upon a prospective randomized trial for which informed consent has been given, then every effort should be made to follow the protocol guidelines, which are designed to answer a protocol question. However, patie...
What is your approach to treat metastatic poorly differentiated thyroid cancer with papillary features?
The easy answer is that there is a role for I-131 if the remnant disease (tumor bed or mets) is iodine avid. Harder and perhaps more realistic is that the test dose of 2-3 mCi is too low and you have to overwhelm the iodine receptor with at least 30 mCi to activate a radiologic response. If you are ...
Would you recommend prophylactic retro-peritoneal RT in an adolescent with paratesticular rhabdomyosarcoma, s/p radical inguinal orchiectomy without a lymph node dissection?
Ideally, in children over 10 years of age with a diagnosis of paratesticular RMS, a retroperitoneal LN sampling (taking 7-12 LNs) at diagnosis should be performed unless obvious gross disease in the nodal region is present. The risk of occult LN involvement is higher in those children 10 years or ol...
Which patients with primary, early-stage NSCLC would you utilize immunotherapy in conjunction with SBRT?
The trial from Chang et al., PMID 37478883 testing SBRT +/- IO for early-stage NSCLC was a randomized phase II trial. Although very exciting results, it's not a phase III trial and does not technically change management. IO agents are not FDA-approved in this setting yet! There are at least 2 phase ...
How do you manage an intramedullary benign nerve sheath tumor post sub-total resection seen on post-operative MRI?
Intracranial schwannomas respond well to low dose SRS (11.5-12 Gy) or SRT (25 Gy in 5 fractions) Slane et al., PMID 28089525 However, both of these approaches use a somewhat higher dose than the spinal cord tolerance doses. Therefore, I would treat the patient on a radiation delivery system equippe...