Neoantigen dendritic cell vaccination combined with conventional chemotherapy for a patient with advanced transverse colon cancer.

Over the past decade, neoantigen dendritic cell (DC) vaccination has emerged as a promising personalized cancer immunotherapy based on genomic analysis. To further assess the clinical utility of this approach, additional data on the efficacy of neoantigen DC vaccination are needed. A 65-year-old male patient underwent curative surgical resection for pStage IIIB transverse colon cancer, followed by adjuvant DC vaccination combined with conventional chemotherapy for 6 months postoperatively. The neoantigen DC vaccination effectively reduced elevated carcinoembryonic antigen levels. Moreover, cytotoxic T lymphocytes (CTLs) isolated from the patient's peripheral blood demonstrated specific recognition of the neoantigen peptides. Our findings suggest that CTLs recognizing tumor-specific neoantigens may play an important role in immune surveillance against cancer recurrence. The patient remains alive and disease-free 16 months after surgery.