Radiation Oncology
Expert insights on radiation treatment planning, techniques, toxicity management, and multimodal cancer care.
Recent Discussions
How do you manage recurrent CNS ependymoma?
Data for treating recurrent ependymoma comes mostly from single institutions retrospective series. Patients with recurrent ependymoma should be restaged with spine MRI and LP cytology, evaluated for maximal safe resection, re-irradiation, and clinical trials. If the disease is localized, many radiat...
Is it appropriate to use a hypofractionated schedule of 40 Gy in 15 Fx for LS-SCLC?
The study from Norway used 42 Gy in 3 weeks. CONVERT had gr 3 or 4 esophagitis in 18% regardless of QD66 or BID45/3wk. Since I am stuck on 45Gy, I use 45 Gy in 3 wks for incapable, refuse BID or ED-SCLC.
What is the role of radiation in regionally recurrent gastric cancer?
I would treat this like a D2 dissection case that did not receive preoperative chemotherapy. I would treat a large microscopic volume including the tumor bed, gastric remnant and the celiac axis, porta, and splenic nodes. IMRT to 45Gy would probably be necessary in my mind in this case. I would use ...
What factors do you use to determine whether an enlarging lesion after SRS is radionecrosis versus progression?
This is a challenging issue, especially in a community setting where patients had not been treated with SRS before, and radiologists are now confronted with post SRS scans. The two major things that clinicians can look at are:1) T2 - T1 mismatch - if there is a correspondence between the contrast-en...
How do you approach a solitary pelvic nodal recurrence following definitive radiation therapy to the prostate/SV?
Briefly, I agree with @Dr. First Last and I occassionally offer treatment to solitary nodal disease, most commonly seen in the postprostatectomy, post-salvage RT setting. I'm generally not offering SBRT to nodal disease, since I think of the nodal basin needing RT (like 45 Gy with SIB to nodal disea...
What is your approach for post-implant dosimetry when utilizing a focal LDR prostate implant for salvage after a localized primary LDR brachytherapy failure?
We have recently done a few patients with LDR brachy after primary EBRT failure. MRI showed disease localized to one lobe and thus we implanted half of prostate. The d90 for implanted region we aimed for was 100% but two precautions we took were: one avoid bladder neck region and second use space OA...
Do you recommend imaging surveillance vs adjuvant RT for a large low grade sarcoma of the lower extremity with multiple positive margins?
I would recommend evaluation for re-resection to get negative margins. I would also make sure the pathology is reviewed by an experienced sarcoma pathologist, to confirm the type of histology and the grade.For low-grade sarcomas (not desmoids, dermatofibromas) in cases where re-resection isn't possi...
Would you give post operative radiation for a pT1N0 parotid low grade mucoepidermoid carcinoma with positive margin on the facial nerve to an adolescent?
This is clearly a challenging situation. I would always suggest first discussing the case with the pathologist and the surgeon to find out about the positive margin. Some surgeons will say that the margin is not truly positive and that it is just an artifact of the operation. You may change your tre...
When is it appropriate to recommend a diverting colostomy for treatment of anal cancer or low lying rectal cancer?
If there is bowel obstruction/ near obstruction, recto-vaginal or rectovesical fistula formation.
What dose constraint do you use for the brainstem for repeat cranial irradiation?
This depends on the disease I am treating, the interval time from initial radiation, prior radiation dose and fractionation. and whether or not I am re-irradiating by fractionated or radiosurgery. If this is a recurrent high grade glioma such that the brainstem was previously treated up to 54 to 60 ...