Radiation Oncology
Expert insights on radiation treatment planning, techniques, toxicity management, and multimodal cancer care.
Recent Discussions
How do you minimize urethral dose when doing LDR prostate seed brachytherapy with small glands (<20 cc)?
These cases can be challenging, especially when you approach the 10 to 15cc range. I’ve approached them using back to back sources in the peripheral needles, and loading the central needles in a manner to minimize the 150 isodose line overlap with the urethra. One should pay special attention at the...
How do you decide which local consolidative therapy to offer for a single lung metastasis in a patient with metastatic colorectal cancer?
SBRT, then more chemotherapy.
How much volume reduction do you typically observe following radiotherapy for a meningioma?
Assuming this is for indolent grade I meningiomas, retrospective studies show that the range for volume reduction following fractionated radiotherapy or stereotactic radiosurgery can be anywhere from 13% to 61%. Also, the interval time to volume reduction may be anywhere from 6 months to years. In s...
What constraints do you use for the external beam portion of radiation when combined with brachytherapy boost?
Simply “scale” down your constraints for the bladder, rectum, and fem heads for a 44fx regimen down to 25. It’s a simple mathematical calculation. No need to convert for small bowel or penile bulb, as these tissues should not get a dose from the implant. The scaled constraints allow for some flexibi...
If a patient who had mastectomy and implant reconstruction for T1N0 breast cancer developed a new lesion years later in the axillary tail, should the implant be removed and the chest wall treated or would you consider APBI to spare the implant?
First we need to confirm the CW recurrence or new primary. The presence of DCIS in axillary twill would favor new primary. Either way, even if the entire chest wall needed to be treated, the implant need not be removed. The patient would need to be counseled about the effects on cosmetic outcome.
How do you sequence TTFields into your salvage therapy plan for patients with recurrent glioblastoma?
For those patients who have not had TTF previously (we do not offer it in the salvage setting if they had received it initially), we evaluate for clinical trial eligibility first, and offer this option (unless for clinical reasons resection is urgently indicated). If a clinical trial is available, a...
What screening criteria do you use to give patients IV contrast for the CT sim?
This is an extremely frustrating and commonly encountered scenario in radiation oncology clinic (and the diagnostic CT suite). What is most frustrating is how stubbornly the dogma of contrast-induced nephropathy has persisted, and the vast amount of needlessly wasted resources spent worrying about i...
How do you manage breast lymphedema after radiation?
We refer to lymphedema physical therapist for management.
Do you use a custom wax tongue immobilizer for oral cavity radiotherapy?
We have not used a device which aimed primarily to immobilize the tongue. Rather, we use a customized device (“radiation guards”) which primarily aims to reduce backscatter from metal fillings or crowns in the teeth into the surrounding gums and adjacent tongue. This device has been described by Ben...
Do you typically recommend re-resection for secretory carcinoma of the parotid with focal positive margins?
In my experience, it is always difficult finding the focal margins in question on re-resection in the post-op parotid bed, if not downright impossible. Most of the re-resection margins come back negative in case of focally positive margins. Unless re-resection surgery entails wide local excision tha...