Radiation Oncology
Expert insights on radiation treatment planning, techniques, toxicity management, and multimodal cancer care.
Recent Discussions
Which patients with rectal cancer who have not received neoadjuvant treatment do you offer adjuvant radiation to?
In order to answer this question, we may need to step back and first review the indications for radiation treatment in the neoadjuvant setting.Neoadjuvant concurrent chemoradiation or short course radiation treatment is considered to be part of the standard treatment (recommended by guidelines) for ...
Do you administer prophylactic antibiotics for GU procedures?
The common GU procedures performed in radiation oncology are transperineal brachytherapy and transperineal retroprostatic hydrogel insertion. Rarely transrectal biopsy or transrectal intraprostatic injections may be performed by radiation oncologists. I don't believe any randomized studies looking a...
Is there a PSA value below which you would not offer salvage radiation post-prostatectomy?
I am commonly asked the inverse question: if I use a "PSA cutoff" whereby a rise beyond this value will strongly favor treatment with post-op radiation. I think it is difficult to have a set value that applies for all patients, as the decision to treat should be individualized to patient and disease...
How would you adjust your CTV for a locally advanced rectal cancer case with invasion of the prostate?
I’m not aware of any “high level” guidance on this specific question. Most cases I see have limited invasion of the peripheral zone of the prostate and/or seminal vesicles. With the assistance of a registered MRI, I contour the gross primary tumor and add at least a 1 cm margin into the prostate. I ...
How would you treat a carcinoma in situ of the larynx with involvement of the false cord and arytenoid mucosal surface?
63 Gy/28 fractions larynx only
Is there a chest wall constraint you typically use for 60 Gy in 15 fraction NSCLC treatment?
We generally keep chest wall Dmax <110% and keep as much 105% out of the chest wall as possible, with a very low-priority goal of V4000 cGy <30 cc. I am definitely not strict about this in most cases, especially the volumetric goal.
What dose would you use for a plaque brachytherapy for a melanoma involving the iris?
The following isotopes have been used for radioactive plaque therapy to treat choroidal melanomas: 125I, 103Pd, and 131Cs as low-energy seeds, and 106Ru as β emitter. The dose used for uveal melanomas is between 80-90Gy with most studies reporting doses ~85 Shields et al., PMID 10980767. In this lar...
For esophageal and gastroesophageal junction cancers, which lymph nodes are metastatic versus regional?
I would say the short answer is no, hilar nodes are not regional nodes for esophageal of gastroesophageal junction cancers. The long answer would require a definition of what we're talking about when we say lymph nodes are "regional". This may have different definitions depending on the setting. F...
What BED10 do you aim for when prescribing hypofractionated treatment for ultra-central tumors of the lung?
BED10 (3) for the regimens listed above (and a few others) 50 Gy/5 fx: 100 Gy (216.67 Gy) 60 Gy/8 fx: 105 Gy (210 Gy) 70 Gy/10 fx: 119 Gy (233.33 Gy) 62.5 Gy/10 fx: 101.56 Gy (192.71 Gy) 60 Gy/15 fx: 84 Gy (140 Gy) 72 Gy/18 fx: 100.8 Gy (168 Gy) 77 Gy/25 fx: 100.7 Gy (156.05 Gy) 79.5 Gy/30 fx: 100.6...
Is there any evidence that radiotherapy can worsen balance, dizziness, or vertigo in patients treated for vestibular schwannoma due to transient edema?
While the answer from Dr. @Dr. First Last addresses a much broader category of patients treated with SRS, we have looked specifically at post radiation side effects after treatment of vestibular schwannomas treated with either SRS (12.5 Gy), hypofractionated SRS (hSRT with 5 fractions of 5 Gy), or c...