PCN35 Systematic and Structured Reviews of the Disease Burden in Patients with Microsatellite Instability High (MSI-H) or Mismatch Repair Deficient (DMMR) Colorectal Cancer (CRC)

Abstract

Literature reviews were undertaken to assess global disease burden of MSI-H/dMMR CRC Medline®, Embase®, Cochrane, EconLit, CRD York databases and select conferences were searched for studies reporting burden of MSI-H/dMMR CRC globally. Evidence was searched during 2009-19 (economic burden) and 2014-19 (epidemiology, treatment patterns and humanistic burden). Of 41,296 records screened - epidemiology (N=41), economic (N=2) humanistic burden (N=2) and treatment patterns (N=4) studies were reported for MSI-H/dMMR CRC. Included evidence showed prevalence of MSI-H/dMMR CRC ranged from 5.8% to 22% across disease stages with rates higher in earlier stages, >50 years of age, females, and Caucasians. Three country-specific real world studies reported common use of 5-FU- based treatments with either irinotecan, or oxaliplatin and with or without an EGFR or VEGF inhibitor for 1L MSI-H CRC. In response to a 2018 survey of global healthcare practitioners on their intended treatment plan for various case scenarios, 43%(1st line), 62%(2nd line) and 54%(3rd line) indicated preference for use of an immune checkpoint inhibitor. In a single institution, non-randomized study of 5-FU-treated patients, overall symptom burden (OR 2.48; 95% CI, 1.29-4.74) pain (3.06 [1.61-5.84]), fatigue (2.78 [1.41-5.49]), sleep (2.52 [1.32-4.08]); and drowsiness (2.51 [1.32-4.78]) was greater among those with MSI-H versus microsatellite stable tumors. Published evidence on the disease burden of MSI-H/dMMR CRC is sparse. Given the recent approvals and increased clinical development of immune checkpoint inhibitors in this high unmet need area, real-world and economic studies could further help to assess the disease burden.