Radiation Oncology
Expert insights on radiation treatment planning, techniques, toxicity management, and multimodal cancer care.
Recent Discussions
Would you dose escalate for prostate cancer extending to the penile bulb, towards the urethra, and close to anorectal junction?
I agree with Dr. @Dr. First Last's inquiry regarding the definition of "dose escalation" in this setting. In my mind, the question relates not so much to dose as to target coverage. I would not alter dosing on this basis but would carefully assess the appropriate target with pelvic MRI and PSMA PET-...
How do you approach treatment of sub-total resected ZFTA fusion ependymoma after radiation therapy in a young adult?
Thank you for asking.ACNS0831 has shown that there is no benefit of adjuvant chemotherapy in patients with incomplete resection. This was based on a comparison between ACNS0121 where patients did not receive any chemo after XRT and ACNS0831 where all patients with residual received adjuvant chemothe...
How long should one wait before biopsying a persistently palpable mass of early stage nodular lymphocte predominant Hodgkin lymphoma (NLPHL) after radiation?
There is no set time frame for biopsy. I will recommend a PET/CT 3 months post treatment before making a decision on biopsy . The sensitivity, specificity, PPV and NNP of PET in NLPHL is 99 - 100 % (Grellier et al. Eur. J. Nucl . Med. mol Imaging 2014 ).
Would you irradiate all borderline suspicious lymph node regions on PET/CT in stage IIA nodular lymphocyte predominant Hodgkin's lymphoma treated with ISRT alone?
ISRT fields for lymphocyte predominant HL when treating without chemotherapy should be more generous in the nodal chain region than if treated with chemotherapy. We conducted a survey of expert lymphoma radiation oncologists published in the IJROBP, which demonstrated some differences in opinion. Ho...
What is your preferred treatment for non-contiguous Stage IIA Nodular Lymphocyte Predominant Hodgkin's Lymphoma (NLPHL)?
Prognosis of patients with early stage NLP-HL is excellent with any treatment, and multi-institutional studies have shown 5-year survival rates of 98% (Michael S. et al. Stage I-II nodular lymphocyte-predominant Hodgkin lymphoma: a multi-institutional study of adult patients by ILROG. Blood 2020; 13...
How do you approach delivering ISRT to nodular lymphocyte predominant Hodgkin Lymphoma that has responded on FDG-PET/CT after chemotherapy?
The therapeutic algorithm in stage >I lymphocyte predominant HL is extrapolated from data on classic HL. Thus, I would use the same algorithm as in HL when evaluating RT indication and dose. Omitting radiotherapy is safe, if a favorable response has been documented on PET-CT and the patient has rece...
What is the best treatment volume and dose for a marginal zone orbital lymphoma?
It would depend on the location- retrobulbar, conjunctival or lacrimal gland. Imaging, including MRI, helps in evaluating the site of origin and extent of involvement. Some advocate treating the entire orbit for all orbital lymphomas to be comprehensive, as the total dose is low, and this away we av...
How do you follow patients after radiation treatment for orbital MALT lymphoma?
Local control is extraordinarily high after definitive RT (24 Gy) for orbital MALT lymphoma (>95%). It is not uncommon for patients with retro-orbital disease to have residual masses after RT that remain stable during follow-up. One should be cautious about pursuing additional therapy for presumed "...
Would you require biopsy of both orbits or is unilateral biopsy adequate for a patient with suspected bilateral orbital MALT lymphoma?
Biopsy of one orbit is sufficient if clinical findings and images of the other orbit are all consistent with marginal zone lymphoma (MZL). I’m a little surprised the question of how to treat bilateral MZL of orbit was not asked. Assuming disease is limited to the orbits, radiotherapy to both sites w...
For a MALT lymphoma involving the preseptal orbit only, woud you treat the entire orbit or limit the CTV to the preseptal orbit?
MALT lymphomas of the orbit are one of the extranodal sites for which not treating the entire organ is appropriate, given good outcomes and increased toxicity with the treatment of the entire orbit. So, would give CTV and PTV margin to the imaged lesion. For conjunctival lesions, the entire conjunct...