Radiation Oncology
Expert insights on radiation treatment planning, techniques, toxicity management, and multimodal cancer care.
Recent Discussions
Would you irradiate the prostate in a patient with SpaceOAR in the incorrect location but not invading rectum or prostate?
I would treat without delay if the SpaceOAR gel is not invading the rectum. It is common to see gel placements that are not ideally placed, and we have not seen any unusual or unexpected side effects/complications from this. We still see a dosimetric advantage in our treatment plans, even with a sub...
When evaluating margin status to consider APBI for early stage invasive breast cancer, given the specification for at least 2 mm margins, do you look at the DCIS margin or only the invasive margin?
I take a slightly different approach. Current guidelines for breast conserving surgery allow for no tumor on ink for invasive cancers, even those with DCIS associated. While ASTRO guidelines recommend 2 mm for APBI (Correa et al., PMID 27866865), other guidelines such as the ABS do not for invasive ...
How do you interpret NCCN chemoRT dose recommendations for SCLC which start higher than NSCLC?
I understand the questioner's logic that because SCLC is traditionally considered more radiosenstive than NSCLC, it may seem discordant that guidelines recommend 66Gy for SCLC but 60Gy for NSCLC. However, I would still abide by these guidelines because as the questioner suggests, these doses are bas...
What is the best management for a local recurrence for a stage I NSCLC treated previously with SBRT?
There is little data to guide management in this scenario given high rates of local control with SBRT and a relatively frail patient population at risk for intercurrent death, reducing the number of patients at risk for local failure. Given the lack of data, utilization of first principles and a bit...
What GTV to CTV margin do you typically use for the primary lesion in anal cancer?
I have concerns about even attempting to delineate a GTV for the cephalad portions of many anal canal cancers. An advanced tumor that extends cephalad above the pelvic floor can infest the mesorectal compartment with highly irregular margins. For axial slices at the upper extent of macroscopic disea...
Do you recommend treating pre-chemo volumes to full prescription dose for locally advanced nasopharyngeal cancer following induction chemotherapy?
A modified pre-chemo volume, because for example we are not going to treat air.
What time frame, number of PSAs, and calculator do you use for calculating PSA doubling times?
I typically use only values of 0.10 ng/mL or greater, and at least 3 separate PSA values that are at least 3 weeks apart from each other. The greater the number of PSA values, the more accurate the PSADT calculation will be. I like to use the MSKCC calculator: Prostate Cancer Nomograms: PSA Doubling...
In a patient with a small cell of the esophagus in which trimodality therapy is planned what dose of preoperative radiation would you use and would you utilize BID fractionation?
As is the case with many rare histology malignancies, there is no standard therapeutic approach to the management of small cell carcinoma of the esophagus. Nevertheless, there are small institutional experiences published on this topic to help guide decision making. Since the question refers to a pl...
How would you approach treatment of an elderly patient with recurrent atypical fibroxanthoma (malignant spindle cell neoplasm) after Mohs surgery?
We published our experience of 8 cases of scalp atypical fibroxanthoma treated with XOFT 50 KeV photons as primary therapy. At 24 months, there was one failure which occurred in the only patient who was not debulked prior to radiation therapy.Treating with low energy photons or electrons after the r...
How do you treat the chest wall after mastectomy with an expander?
We have not been treating patients with immediate tissue expander reconstruction with hypofractionated photon post-mastectomy radiotherapy off trial. However, we are excited to be opening @Dr. First Last's A221505 randomized photon study. In addition, we are nearing completion of enrollment to NCT02...