Radiation Oncology
Expert insights on radiation treatment planning, techniques, toxicity management, and multimodal cancer care.
Recent Discussions
How do you manage a peripheral NSCLC and a single positive contralateral lymph node?
In this circumstance, I would first confirm pathologically if possible with mediastinoscopy or EBUS. Right-sided tumors have a tendency to spread to ipsilateral lymph node stations only and spread to the contralateral mediastinum, particularly in the absence of ipstileral involvement, would be unusu...
Is weekly Cisplatin considered a valid alternative to Cisplatin cycles every 3 weeks as part of definitive chemo-radiation for muscle invasive bladder cancer?
None of the RTOG trials had this approach, but extrapolating from head and neck cancer (cisplatin 30mg/m2) or cervical cancer (40mg/m2), people in the community are using weekly cisplatin. As far as data, there is a phase II study from Australia utilizing cisplatin 35mg/m2 weekly for 6-7 cycles show...
For elderly patients with locally advanced rectal cancer who are not candidates for surgery or chemotherapy, what would be an appropriate palliative regimen?
There is an old paper from Princess Margaret Hospital ~1980, called "Is the Miles operation really necessary for the treatment of rectal cancer?". (Editor note: 1993 Update). These are patients who were medically inoperable or refused surgery. I believe doses were about 40 Gy. Remember that this was...
What is the best approach to management of newly diagnosed intermediate or high risk prostate cancer in a patient with high grade non-muscle invasive bladder cancer?
Perhaps the term "Best Approach" should be eyed with skepticism in the field of genitourinary radiation oncology. Is there extensive disease in the bladder, focal recurrences, or no visualizable lesions? The maintenance BCG element of the question suggests the patient has minimal measurable disease ...
Is there a role for post-operative chemoradiation therapy in fully resected, margin-negative T3N1 NSCLC?
I assume you're talking about T3 for chest wall invasion, and I think the answer is probably no routine role for RT for this individual risk factor. If you look at surgical series, invasion of the chest wall IS a risk factor for both positive surgical margins, and local recurrence. But if you limit ...
For breast cancer patients requiring staging, should one order a CT C/A/P & bone scan or PET scan?
For locally advanced disease (T4 or N2), I would favor PET/CT because of the higher yield for identifying metastatic disease. It is also important for the radiation oncologist because of the higher likelihood of identifying of involved IM nodes and level 3a and supraclavicular nodes which can change...
What dose do you typically use when retreating locally aggressive and recurrent SCCs of the scalp (with no regional or distant mets)?
Not much great data to support this contention, but my general practice is EQD2 of 70-80 Gy in a continuous course using shrinking field technique, depending on prior radiotherapy and tolerance of nearby organs at risk. For gross disease, concurrent systemic therapy may be worthwhile in patients tha...
When performing IMRT treatment planning for head and neck cancer, how do you instruct your dosimetrists to manage the optimization process for targets that are very close to the skin surface (or with PTVs that extend into air), yet the skin itself is not at risk?
We use method #2 described - creating a faux bolus in the planning system without changing the 3mm PTV expansion on CTV. If in the re-calculation process the dose is not adequate to gross disease under the skin or at the anterior commisure, physical bolus may be applied. In reality, we rarely use ph...
Do you recommend altered fractionation when using cetuximab with head and neck RT?
The 5-year update of the randomized study of RT vs RT and cetuximab for HN cancer added additional factors related to better outcome in patients receiving cetuximab (in addition to the findings that only oropharyngeal cancer benefited, published previously in the NEJM paper). The additional factors ...
What is the rate of dementia following whole brain radiotherapy in patients with brain metastases who survive for over a year?
To answer this question we need to have a common understanding of "dementia." I think that those of us who follow patients long-term after WBRT all agree that there are cognitive changes that develop. From the placebo arm of RTOG 0614 we know that at 6 months 65% of patients experienced cognitive dy...