Pembrolizumab for Microsatellite Instability-High or Mismatch Repair Deficient Small Bowel Adenocarcinoma or Appendiceal Adenocarcinoma


( Last Updated : October 22, 2021)
Project Line:
Health Technology Review
Project Sub Line:
Rapid Review
Project Number:
RC1381-000

Details


Question

  1. What is the clinical effectiveness of pembrolizumab monotherapy in patients with microsatellite instability-high or mismatch repair deficient (MSI-H/dMMR) small bowel adenocarcinoma or appendiceal adenocarcinoma?
  2. What is the cost-effectiveness of pembrolizumab monotherapy in patients with MSI-H/dMMR small bowel adenocarcinoma or appendiceal adenocarcinoma?
  3. What are the evidence-based guidelines regarding the use of pembrolizumab for the treatment of MSI-H/dMMR small bowel adenocarcinoma or appendiceal adenocarcinoma?

Key Message

Some adult patients with microsatellite instability-high (MSI-H)/mismatch repair deficient (dMMR) small bowel adenocarcinoma might benefit from pembrolizumab in controlling the disease (i.e., some patients achieved a partial or complete response after treatment). These findings are based on 2 single-arm studies (i.e., no comparator) with fewer than 20 patients in each study, which limits the certainty of the findings. The longer-term benefit of pembrolizumab is unclear, as some outcomes (e.g., progression-free survival, overall survival) were not reached at the time of data analysis. The safety of pembrolizumab in patients with MSI-H/dMMR small bowel adenocarcinoma is unknown (no evidence was found for this population). No evidence was identified regarding the clinical effectiveness of pembrolizumab monotherapy for patients with MSI-H/dMMR appendiceal adenocarcinoma. No evidence was identified regarding the cost-effectiveness of pembrolizumab monotherapy for patients with MSI-H/dMMR small bowel adenocarcinoma or appendiceal adenocarcinoma. No evidence-based guidelines were identified regarding pembrolizumab monotherapy for patients with MSI-H/dMMR appendiceal adenocarcinoma. One guideline was identified that recommends pembrolizumab as an option for initial or subsequent therapy in patients with advanced or metastatic MSI-H/dMMR small bowel adenocarcinoma.