Radiation Oncology
Expert insights on radiation treatment planning, techniques, toxicity management, and multimodal cancer care.
Recent Discussions
When, if ever, would you consider dose de-escalation for HPV-associated non-oropharyngeal HNSCC?
This is a very complex question, as the issues of dose, and de-escalation can be difficult to sum up in an hour lecture let alone a Mednet query. Personally, for me, efforts to lessen volume and doses to subclinical disease are a bit more interesting.Quoting Cmelak et al., PMID 34043410 (2021) in an...
Do you recommend adjuvant radiation in patients with intrahepatic cholangiocarcinoma (IHCC) resected with a positive margin (R1 resection)?
When considering the competing risk of distant mets, the probability of isolated local failure in this disease is probably very low and treatment of the positive margin may not result in a clear benefit. Patients with intrahepatic cholangiocarcinoma have about a 70% or more distant failure rate, and...
What percentage of your breast cancer patients do you plan using IMRT vs 3D?
I think this happens to hinge on your definition of IMRT. Until it became a billing issue, FiF/forward planned segmented treatments were known as IMRT. When it became concerning that billing these as IMRT would become costly for Medicare and commercial payors, the radiation oncology did some sleight...
At what PSA level would you consider restaging a patient who was treated with ADT and radiation and had undetectable PSA?
The criteria for defining PSA relapse after radiation therapy remains the Phoenix criteria (see Roach et al., PMID 16798415), which is essentially nadir + a 2 point rise in serum PSA. Thus, a patient who achieves an undetectable PSA on ADT/RT but then experiences a PSA rise would not meet PSA relaps...
Do you use more stringent liver constraints when treating HCC with SBRT in patients who are CP B8/9 or C?
CP C patients are typically excluded from SBRT studies due to unacceptably high toxicity risks. In my practice, I do not offer SBRT to CP C patients. For those with CP B8 or B9 cirrhosis, I aim to spare at least 700 cc of uninvolved liver from receiving 15 Gy or more when delivering 5-fraction SBRT....
How do you approach boost to the lumpectomy cavity AND 4 lymph nodes with extra-nodal extension when treating breast cancer with hypofractionation?
For breast/chest wall + RNI, I have transitioned to moderate hypofractionation giving 40 Gy/15 fractions. I don't see a clear role for standard fractionation; with 4+ nodes, the question is ALND but if you are giving RT, I'm not sure I see that as an indication for standard fractionation. Followi...
Do you routinely use imaging (US, whole body iodine scans etc.) to follow papillary or follicular thyroid cancer after thyroidectomy and RAI therapy?
I am unaware of any prospective data suggesting a DFS or OS benefit to periodic imaging in patients with well differentiated thyroid cancer; that being said, beyond annual MMGs for our breast cancer patients, is there any benefit to any surveillance imaging in any malignancy? That has been recently ...
For patients with metastatic cancer on a systemic therapy regimen that includes bevacizumab, are you comfortable treating brain metastases (SRS or WBRT) without holding bevacizumab?
Multiple prospective trials have demonstrated the safety of combined bevacizumab and radiosurgery (from both recurrent GBM and brain mets) with some data to actually demonstrate a protective effect against radionecrosis. No significantly increased synergistic risk of intracranial bleed has been obse...
What is the role of radiation therapy in recurrent Rosai-Dorfman disease after surgical resection, which manifests as many cutaneous lesions on the arms and buttocks?
I agree with Dr. @Dr. First Last. When I was in training, we reviewed the cases at MD Anderson. Radiation was only used for 9 patients (infrequently), and local control was achieved in 4 patients. So very small numbers, with uncertain benefits. Median RT dose 36 Gy. In the setting of multifocal dise...
How do you assess whether a patient will be a good DIBH candidate for lung or abdomen treatments?
Assessments are made at the time of simulation. Every patient has a motion assessment performed to determine the degree of motion management required. Typically, if a patient has >1 cm of motion, we will determine if DIBH is appropriate. Patients undergo a coaching protocol using audio/visual feedb...