Maintenance therapy of low-dose nivolumab, S-1, and leucovorin in metastatic pancreatic adenocarcinoma with a germline mutation of MSH6: A case report

Front Immunol. 2022 Dec 13:13:1077840. doi: 10.3389/fimmu.2022.1077840. eCollection 2022.

Abstract

Immune checkpoint inhibitors (ICIs) provide substantial benefits to a small subset of patients with advanced cancer with mismatch repair deficiency (MMRD) or microsatellite instability (MSI), including patients with pancreatic ductal adenocarcinoma (PDAC). However, the long duration of ICI treatment presents a considerable financial burden. We present the case of a 63-year-old woman with metastatic PDAC refractory to conventional chemotherapy. Genetic analyses identified an MSH6 germline mutation and a high tumor mutation burden (TMB). Complete response (CR) was achieved after a short course of low-dose nivolumab (20 mg once every 2 weeks) with chemotherapy. CR was maintained for over 1 year with low-dose nivolumab and de-escalated chemotherapy without any immune-related adverse events. This case supports the further exploration of low-dose, affordable ICI-containing regimens in patients with advanced MSI-high/TMB-high cancer.

Keywords: case report; maintenance therapy; mismatch repair; nivolumab; pancreatic ductal adenocarcinoma.

Publication types

  • Case Reports

MeSH terms

  • Adenocarcinoma* / drug therapy
  • Adenocarcinoma* / genetics
  • Adenocarcinoma* / pathology
  • DNA-Binding Proteins / genetics
  • Female
  • Germ-Line Mutation
  • Humans
  • Leucovorin / therapeutic use
  • Middle Aged
  • Nivolumab / therapeutic use
  • Pancreatic Neoplasms* / drug therapy
  • Pancreatic Neoplasms* / genetics

Substances

  • Nivolumab
  • Leucovorin
  • DNA-Binding Proteins