Radiation Oncology
Expert insights on radiation treatment planning, techniques, toxicity management, and multimodal cancer care.
Recent Discussions
Would you consider SBRT to a perirectal node after previous external beam and prostate brachytherapy?
It is dependent on many variables. If the perirectal lymph nodes are the only site of metastatic disease, then radiation should be considered. The risk of radiation needs to weighed against the possibility of cure. For instance, if the patient presented with a PSA of 80, then the likelihood that the...
Is there a subset of patients with metastatic breast cancer in whom you would consider locoregional therapy?
E2108 is a negative trial for LRT for stage IV disease. We need to see the publication to see details. The issue is if this trial had enough power to detect a difference. The trial was designed to detect an improvement in 3 year OS rate from 30% with OST alone to 49.3% for OST+LRT. The final results...
Are there any specific planning techniques that are used to avoid underdosing the match line in a single isocenter breast plan treating the chest wall and supraclavicular region?
I tend to use a high single iso match when possible to limit lung dose through the AP SCV. What we do is open up a segment from the SCV into the tangent to heat up the match and avoid underdosing of the axilla. Well seen in Figure 6.16 in this treatment planning book.
Would you irradiate the breast of a patient with an unknown primary malignancy manifesting as bulky axillary adenopathy and non-specific poorly differentiated carcinoma histology?
Incidences of occult breast primary has reduced with the advent of MRI imaging. If the IHC of the node doesn’t support breast primary (GATA 3 or mammoglobin are breast specific markers), then I would not treat the breast.
How do you manage patients with pancreatic adenocarcinoma who progress during neoadjuvant FOLFIRINOX, such that borderline resectable disease is now unresectable but still localized?
Great question; this area is rapidly evolving. I hope some of the ViewRay crowd will see this and chime in. We give ablative doses of radiation (~100Gy BED). That results in survival that is similar to surgery in patients like this (inoperable in an aggressive surgery practice at MSKCC, MSS in prepa...
Would you consider prostate SBRT in a patient with focal extracapsular extension?
Most of the time, the concern for ECE is based on MRI findings. Some of the time the concern for ECE is based on broad capsular contact or irregularity of the capsule. Previous studies have demonstrated that the distance of actual microscopic ECE is 5 mm or less. So suspected ECE or early ECE is inc...
What rates of hemorrhage do you quote to patients receiving SRS/fSRT to intact brain metastases?
I agree with @Dr. First Last. I have seen only a few hemorrhages within 60 days of SRS, and the majority were within 7-14 days, which would be unlikely for SRS, and these were predominantly in melanoma and RCC, lesions that would be prone for hemorrhage. So I would not quote a number since this is a...
What CTV expansion volumes would you recommend for a large, unresectable, symptomatic desmoid tumor of the neck?
I would be generous. 2 cm. I’m heavily influenced by "don’t miss and don’t underdose". I appreciate the risk of collateral damage and follow my patients indefinitely, now up to 42 years.😳 I’m acutely aware of the major complications I’ve caused and the recurrences I might have prevented. A difficult...
How do you approach subsequent WBRT following prior brainstem SRS/fSRT?
So I’m assuming this patient who now needs WBRT after SRS for brainstem mets needs it because of elsewhere recurrence. Frankly, I don’t really have a WBRT constraint and ideally, the SRS was over 6 months ago but if the patient needs WBRT I would proceed. I would discuss the potential risk of radion...
Do you have a goal isodose line coverage for skin in the setting of post mastectomy RT with expanders in place?
I don't have a separate goal for skin dose per se in these cases; I primarily look at coverage. In terms of skin dose for these case, I only worry when there are features concerning for skin recurrence and when using higher energy photons.