Radiation Oncology
Expert insights on radiation treatment planning, techniques, toxicity management, and multimodal cancer care.
Recent Discussions
Do you recommend imaging surveillance vs adjuvant RT for a large low grade sarcoma of the lower extremity with multiple positive margins?
I would recommend evaluation for re-resection to get negative margins. I would also make sure the pathology is reviewed by an experienced sarcoma pathologist, to confirm the type of histology and the grade.For low-grade sarcomas (not desmoids, dermatofibromas) in cases where re-resection isn't possi...
Would you give post operative radiation for a pT1N0 parotid low grade mucoepidermoid carcinoma with positive margin on the facial nerve to an adolescent?
Yes. Unfortunately, while the risk of second malignancy is not insignificant in an adolescent, the risk of recurrence on the facial nerve margins is expected to be quite high. Recurrence in the future along the nerve would most likely lead to sacrifice of the nerve and the need for adjuvant RT.
When is it appropriate to recommend a diverting colostomy for treatment of anal cancer or low lying rectal cancer?
If there is bowel obstruction/ near obstruction, recto-vaginal or rectovesical fistula formation.
What dose constraint do you use for the brainstem for repeat cranial irradiation?
This depends on the disease I am treating, the interval time from initial radiation, prior radiation dose and fractionation. and whether or not I am re-irradiating by fractionated or radiosurgery. If this is a recurrent high grade glioma such that the brainstem was previously treated up to 54 to 60 ...
Is there evidence to suggest that SRS/SBRT for spine or bone metastases provides faster and more durable palliative relief or soft tissue decompression than a fractionated course?
This question has two components. One is faster pain relief from spine metastasis, and the other is epidural tumor control from SRS/SBRT over EBRT. The answer is yes, but there has been no direct comparison. RTOG 0631 asked similar question, and is closed meeting the accrual, waiting for the results...
How do you interpret and utilize PSA values in patients on dialysis?
There appears to be no clinically relevant impact on total serum PSA, whereas free PSA and % of total can be impacted in a membrane type-dependent manner to where % free PSA is of less utility for screening. Thus, total serum PSA seems reasonable to continue as marker of biochemical control post-tre...
Would you recommend post-operative radiation to an oligometastatic subcutaneous lesion resected with positive microscopic margins?
Probably not. I would need to know more specific details on the situation before making a recommendation.
When do you consider is too late after resection to offer adjuvant therapy for high grade osteosarcoma?
Regarding the time to resume chemotherapy post resection in osteosarcomas, I do not feel there is a strict cut-off time frame that would render one unlikely to benefit, however, there is well cited literature that shows that a delay of >21 days (3 weeks) leads to a higher risk of death (57%) compar...
Do you ever start immunotherapy along with WBRT in patients with PDL1 >50% metastatic NSCLC with significant visceral tumor burden in addition to symptomatic brain mets?
The general rule in the era of chemotherapy has been to hold concurrent therapy in the context of palliative radiation--in particular whole brain radiation--due to added side effects. These principles have shifted to some extent in the context of targeted therapies and checkpoint inhibitors as exper...
Is superficial underdosing of hypofractionated breast RT acceptable in patients with a large breast separation?
The 3D dose distribution and DVHs should be carefully reviewed for target volume coverage, particularly if the lumpectomy bed PTV is superficial. The most important consideration is adequate coverage (>/=95%) of the tissue included in the region of the lumpectomy bed PTV. Whole breast PTV coverage i...