Radiation Oncology
Expert insights on radiation treatment planning, techniques, toxicity management, and multimodal cancer care.
Recent Discussions
Does the dose rate of an external beam linear accelerator matter in terms of radiobiology?
Per Hall, "The dose-rate effect caused by repair of sublethal damage is most dramatic between 0.01 and 1 Gy/min; [a]bove and below this dose-rate range, the [cell] survival curve changes little, if at all, with dose rate." "Old" linacs could pump out about 6 Gy/min; new ones, up to 24 Gy/min. Sublet...
How do you boost patients with squamous cell carcinoma of the cervix or upper vagina with invasion of the posterior bladder?
It depends on the distribution of diease and whether there is a fistula or not. If there is relatively small bladder invasion, intracavitary may provide adequate coverage; MRI-based planning is recommended. If it is a large tumor with very extensive bladder inolvement (which usually is associated wi...
Per 2016 NCCN guidelines, is the addition of 6 cycles docetaxel now the standard of care for all (NCCN) high and very-high risk prostate cancer patients receiving definitive XRT/ADT?
Last year, the results of RTOG 0521 were presented at ASCO and showed that adjuvant docetaxel led to a small improvement in overall survival for men with high risk prostate cancer. To briefly recap, 563 eligible subjects were randomized to standard-of-care external beam RT (72-75.6Gy, with 46.8 to r...
Is there any data on an effective RT regimen (dose/fractionation) for inducing an abscopal effect using a PD-1 inhibitor in refractory Hodgkin's lymphoma?
I'm not aware of any published data for HL. There is a phase I-II study on low-grade B-cell lymphoma: "In situ vaccination with a TLR9 agonist induces systemic lymphoma regression: a phase I/II study" by Brody et al (J Clin Oncol. 2010 Oct 1;28(28):4324-32) that used a dose of 2 Gy x 2. There is an ...
Is it acceptable for a medical oncologist to use Xeloda in place of 5FU when treating GI sites other than rectal?
Yes, we have extrapolated from anal cancer and gastric. Xeloda is safer better tolerated than traditional 5FU.
Are there situations where it's appropriate to offer postmastectomy radiation therapy to patients with biopsy-proven M1 disease?
The two randomized studies evaluating benefit of local treatment for stage IV breast cancer at diagnosis were negative for the end point of improving survival. One from Turkey which randomized patients to upfront local treatment vs. none showed a trend for improved survival for bone only disease on ...
How should masticator space involvement be defined: anatomically or by AJCC's vague definition with regards to Nasopharynx Cancer?
That's a great question. I found the following article (linked below), which showed that the anatomic definition of masticator space independently predicts for increased locoregional recurrence and overall survival, and that since the mandibular nerve passes into the anatomic masticator space, that ...
Does a rare histology prostate cancer, such as ductal or mucinous, change your typical management recommendations?
Intraductal cancers are often associated with Grade 4 prostate cancer and getting a mpMRI and performing a fusion TRUS/mpMRI bx of any PiRads 3, 4 or 5 cancer to r/o Grade 4 would be of value to recommend treatment as opposed to active surveillance in an otherwise Gleason score 6 PC. If Grade 4 is c...
Do you transfuse anemic head and neck cancer patients undergoing chemoradiation?
No, never have.
Do you routinely recommend prophylactic cranial irradiation for stage I small-cell lung cancers treated with lobectomy and adjuvant chemotherapy?
PCI was 'associated' with better long-term survival even in stage 1, and age and size factors do not seem to matter. However, as the information gets divided, fewer patients fall into each cohort.A recent study published in the JCO, analyzing over 1,000 patients in the NCDB, found that thoracic radi...