1.Successful Treatment of Advanced Gastric Cancer with Brain Metastases through an Abscopal Effect by Radiation and Immune Checkpoint Inhibitor Therapy
Momotaro MUTO ; Hirotaka NAKATA ; Kenichi ISHIGAKI ; Shion TACHIBANA ; Moe YOSHIDA ; Mizue MUTO ; Nobuyuki YANAGAWA ; Toshikatsu OKUMURA
Journal of Gastric Cancer 2021;21(3):319-324
The abscopal effect refers to the phenomenon in which local radiotherapy is associated with the regression of metastatic cancer that is distantly located from the irradiated site.Here, we present a case of a patient with advanced gastric cancer and brain metastases who was successfully treated with brain radiotherapy and anti-programmed death-1 (PD-1) therapy-induced abscopal effect. Although anti-PD-1 therapy alone could not prevent disease progression, the metastatic lesions in the brain and also in the abdominal lymph node showed a drastic response after brain radiotherapy and anti-PD-1 therapy. To our knowledge, this is the first reported case of successful treatment of advanced gastric cancer with multiple brain and abdominal lymph node metastases, possibly through anti-PD-1 therapy combined with brain radiotherapy-induced abscopal effect. We suggest that the combination of brain radiotherapy and anti-PD-1 therapy may be considered as a therapeutic option for advanced gastric cancer, especially when there is brain metastasis.