Some of the mutant
peptides produced by gene mutation transcription and translation have the ability to induce specific T cells, which are called new
antigens. Neoantigen-based
peptide,
DNA,
RNA, and dendritic cell
vaccines have been used in the clinic. In this paper, we describe a lung
metastasis of a
phyllodes tumor patient demonstrating pathological complete response following treatment containing personalized multi-
epitope peptide neoantigen
nano-vaccine. Based on whole-exome sequencing (WES),
RNA sequencing, and new
antigen prediction, several mutated
peptide fragments were predicted to bind to the patient's
human leukocyte antigen (HLA) allotypes, including ten
peptides with high predicted binding affinity for six genes. The pulmonary
metastases remained stable after the four cycles of anti-PD1 and
anlotinib. After the addition of the multi-
epitope peptide neoantigen
nano-vaccine, the
tumor began to collapse and
contracture developed, accompanied by a decrease of
tumor markers to normal, and complete pathological remission was achieved. With the use of the vaccination,
recombinant human granulocyte-macrophage colony-stimulating factor (rhGM-CSF) was used every time, and low-dose
cyclophosphamide was injected every 3 weeks to improve efficacy. Peripheral blood immune monitoring demonstrated immune reactivity against a series of
peptides, with the most robust post-
vaccine T-cell response detected against the
HLA-DRB1*0901-restricted SLC44A5 V54F
peptide.