Radiation Oncology
Expert insights on radiation treatment planning, techniques, toxicity management, and multimodal cancer care.
Recent Discussions
In what situations would immunotherapy alone be appropriate for non-metastatic NSCLC?
Based on our current SOC treatment paradigms for patients who don't have contraindications to definitive treatment options, my short answer would be no. However, few caveats to that no as always. Few examples where I think this would be an appropriate approach based on currently available data. Poor...
Would you recommend XRT treatment fields of a locally recurrent prostate cancer s/p RP similar to salvage vs intact prostate treatment?
I will generally approach the treatment fields similarly to any other post-prostatectomy recurrence. Unless the anatomy is unfavorable, I will try to treat the full CTV per guidelines (the Francophone guidelines were published in 2021 and provide updated guidance). The toxicity rates to treating the...
Is there a volume or size criteria where you feel that standard doses for palliative radiation (8Gy/1fx-30Gy/10fx) are not effective?
At the risk of running off the mathematical rails, I thought about this question from a completely non-clinical viewpoint (from a clinical viewpoint, yes, I would probably use a bit more than 30/10 for a big 10 cm mass). Here are a few assumptions. First, the D-sub-zero (D0) for many tumor systems h...
What maximum volume (in cc's) of small bowel would you allow to receive 45 Gy in a patient with node positive squamous cell carcinoma of the anal canal receiving concurrent chemoradiation with 5-FU/MMC being treated with IMRT?
This is a very good question because this comes up very commonly in female patients. The first thing to recognize is that the 45Gy microscopic dose is overtreatment for anal cancer. Your V35 is probably an effective microscopic dose. From the to 2D and 3D Era, 30.6 Gy in 17 fractions is an effective...
What are your top takeaways in Breast Cancer from ASCO 2023?
SONIA: A notable trial comparing CDK4/6 inhibitors as 1st line vs. 2nd line treatment. AI+CDKi combination therapy as 1st line does not improve OS, 2nd PFS, or QOL compared to combination therapy as 2nd line. Factors such as the site of metastasis, tumor burden, symptoms, cost, and side effects sho...
What is the role of a simultaneous integrated boost in vulvar cancer to the primary and nodes?
We typically do a SIB at 2 Gy per fraction to the vulvar GTV and nodes and then do a sequential boost to follow (CTV is treated at 1.8 to CTV in 25 fractions). Presumably, the nodes could be safely treated at a higher dose per fraction since there is typically not a critical structure in close proxi...
In a patient diagnosed with prostate cancer based on a biopsy many years ago placed on surveillance now with rising PSA, do you require repeat biopsy prior to definitive radiation treatment?
This question raises multiple important points that I will discuss, but given that the question doesnt have patient age or numerous other important factors I will speak generally with multiple assumptions being made that he is ~65yo with >10 years life expectancy, etc:1. The question is in fact wron...
What dosimetric or physics considerations would you take for the treatment of the prostate and pelvic LNs in patients with a penile pump/prosthesis/implant?
We presented this as a poster at the 2016 ARS 98th annual meeting. We looked at 7 prostate cancer patients who had existing penile prostheses - who underwent either salvage EBRT (5) or Curative EBRT (2). All patients completed their respective planned courses without interruption(s). We looked at th...
What dose constraints do you recommend for the heart when treating an intrahepatic cholagiocarcionma with ablative (15 fx) techniques when the tumor is adjacent to the right atrium?
This is a really interesting and great question. The primary considerations for heart dose are prognosis from the cancer in the best case scenario and the risks of subacute and late toxicity. Since the 5yr OS even of resected IHCC is only 25%, that is the best case assumption for ablative RT. 70% of...
Do you use bite block during radiation treatment for base of tongue (BOT) cancer?
Yes, we use intra-oral immobilization for any tongue (or BOT) involvement.Japanese data suggest improvements in immobilization lead to clinically meaningful PTV implications (Doi et al., PMID 28515675) in head and neck cancers. Our in-house data suggests not having a stent on a BOT target requires a...