What happened, in summary

A 52-year-old man was diagnosed in 2021 with poorly differentiated adenocarcinoma involving the esophagogastric junction and gastric cardia. The tumor was HER2-low, microsatellite stable, and had a PD-L1 combined positive score of 5. He began XELOX chemotherapy and had a partial response, then received XELOX with camrelizumab followed by camrelizumab maintenance.

About 14 months after starting treatment, persistent headaches led to brain imaging that found metastases in the right temporal and occipital lobes. He underwent stereotactic radiosurgery, which relieved the headaches. Systemic treatment was then changed to disitamab vedotin (RC48) plus camrelizumab. After two cycles, the brain lesions had shrunk markedly and disease outside the brain remained stable. He continued the combination for about eight months.

Treatment stopped in January 2023 after he developed pneumonitis, which resolved with monitoring and symptomatic care. Follow-up scans continued to improve. By July 2024, the intracranial lesions had completely resolved. Complete remission remained sustained through October 2025, more than 38 months after stopping anticancer therapy, and he reported a normal quality of life.