Microsatellite instability and its impact on nutritional and inflammatory profiles in colorectal cancer

Abstract

Microsatellite instability (MSI) is a critical molecular feature in colorectal cancer (CRC) that not only determines response to immunotherapy but also influences systemic nutritional and inflammatory status. MSI-high (MSI-H) CRC is characterized by heightened systemic inflammation, altered cytokine profiles, and unique gut microbiota compositions. Concurrently, MSI-H patients often exhibit poorer nutritional status, as reflected by lower body mass index, decreased serum albumin, and metabolic dysregulation. These immunonutritional alterations influence patient outcomes by affecting prognosis, response to therapy, and overall survival. This editorial summarizes current evidence linking MSI status with inflammatory and nutritional markers, highlighting the clinical implications of integrating nutritional assessment and inflammatory modulation into the maagement of CRC patients.

Keywords: Microsatellite instability; Colorectal cancer; Nutritional status; Systemic inflammation; Immunotherapy; Gut microbiome

Core Tip: Microsatellite instability-high (MSI-H) colorectal cancer (CRC) represents a biologically distinct subtype characterized not only by its genetic and immunological features but also by unique systemic alterations. Patients with MSI-H CRC often present with heightened systemic inflammation, as evidenced by elevated neutrophil-to-lymphocyte ratio, and impaired nutritional status, including lower body mass index, serum albumin, and altered lipid metabolism. These immunonutritional profiles have direct implications for prognosis, treatment tolerance, and response to immunotherapy. Recognizing the impact of MSI on host systemic status supports a more integrated, personalized approach to patient care, emphasizing the value of nutritional support, anti-inflammatory strategies, and microbiome modulation as potential adjuncts to immunotherapy and conventional treatment.