Jonathan D. Schoenfeld, MD, MPhil, MPH, director, melanoma radiation oncology, physician, assistant professor of radiation oncology, Harvard Medical School, Dana-Farber Cancer Institute, discusses potential combination regimens of low-dose radiation therapy and immunotherapy to treat patients with head and neck cancer.

As these strategies become more targeted, explains Schoenfeld, and as stereotactic body radiation therapy continues to be explored in multiple tumor types and in multiple locations in the body, there are an increasing number of potential combinations that could be evaluated with immuno-oncology agents.

Currently, radiation therapy in the locally advanced setting is given in small daily doses over 4 to 7 weeks. There is some concern, especially when the radiation is administered to a large portion of the body, that it can act as an immune suppresser. This may not be the best way to combine radiation with immunotherapy.

Some data have explored the use of lower doses of radiation, and some preclinical research has suggested that the lower doses may have immunologic effects, both positive and negative, he explains. These combinations will be tested in upcoming trials and may prove beneficial in some cases.

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Dr. Schoenfeld on Low-Dose Radiation Plus Immunotherapy in Head and Neck Cancer

Jonathan D. Schoenfeld, MD, MPhil, MPH, director, melanoma radiation oncology, physician, assistant professor of radiation oncology, Harvard Medical School, Dana-Farber Cancer Institute, discusses challenges with immune suppression with radiation and immunotherapy combinations.

Currently radiation in the locally advanced setting is given in small daily doses over 4 to 7 weeks, says Schoenfeld. There is a concern, especially when the radiation is given to a large portion of the body, that it can act as an immune suppresser. This may not be the best way to radiation in combination with immunotherapy.

However, in the past several years there has been a dramatic increase in focal radiation, including stereotactic body radiotherapy. Because this is a much more focused type of radiation it may better combine with immunotherapy, says Schoenfeld.

Jonathan D. Schoenfeld, MD, MPhil, MPH, director, melanoma radiation oncology, physician, assistant professor of radiation oncology, Harvard Medical School, Dana-Farber Cancer Institute, discusses challenges with immune suppression with radiation and immunotherapy combinations.
 

Dr. Schoenfeld on Preventing Immune Suppression With Radiation and Immunotherapy Combos

Jonathan D. Schoenfeld, MD, MPhil, MPH, director, melanoma radiation oncology, physician, assistant professor of radiation oncology, Harvard Medical School, Dana-Farber Cancer Institute, discusses the potential benefit of using radiation and immunotherapy in combination.

There has been an increasing interest in the combination of radiation and immunotherapy, with multiple pre-clinical studies demonstrating that radiation may help immunotherapies work better and vice versa, says Schoenfeld. Because of the pre-clinical data and the number of studies demonstrating promise with this combination, there is an increasing number of clinical trials that are currently testing radiation and immunotherapy together.

One way researchers are testing this combination is by adding immunotherapy where radiation is already standard of care, says Schoenfeld, including in locally advanced head and neck cancer. The addition of immunotherapy, which is already active in the metastatic setting for squamous cell cancers of the head and neck, may improve results in the locally advanced setting.

Other studies are adding radiation in cases where immunotherapy has already become standard of care, says Schoenfeld, like metastatic lung caner, melanoma, and other advanced diseases. There is a lot of interest in adding radiation in these cases because of the abscopal effect, which is a rare clinical phenomenon where patients get radiation in one area but see an impact elsewhere in the body. This is extremely rare, but in pre-clinical models the addition of radiation to immunotherapy makes this effect more common. Radiation could potentially be used as an in situ vaccine to help immunotherapy work better, says Schoenfeld.

Jonathan D. Schoenfeld, MD, MPhil, MPH

Articles

Dr. Schoenfeld on Low-Dose Radiation Plus Immunotherapy in Head and Neck Cancer

Dr. Schoenfeld on Preventing Immune Suppression With Radiation and Immunotherapy Combos

Dr. Jonathan D. Schoenfeld on Radiation/Immunotherapy Combinations