Gut microbiome and nutritional strategies in gastrointestinal cancers: Clinical implications and therapeutic perspectives

Gastrointestinal malignancies, particularly pancreatobiliary and gastroesophageal cancers, are associated with poor prognosis due to their frequent late-stage diagnosis. Many of these tumors contribute to anorexia-cachexia syndrome and malnutrition, further exacerbating disease progression. Inflammation plays a crucial role in tumor proliferation, and growing evidence suggests that gut microbiome significantly influence inflammatory responses and clinical outcomes in these patients. Additionally, the gut microbiome contributes to carcinogenesis through multiple mechanisms, including DNA damage, activation of oncogenic pathways, and modulation of immune responses. The emerging field of nutritional interventions highlight the microbiome's impact on anticancer drug responses, affecting both chemotherapy and molecular-targeted treatments. Given its pivotal role, microbiome modulation through probiotics, fecal microbiome transplantation, and antibiotics represents a promising approach for cancer prevention and treatment. In this review, we explore the intricate interplay between gut microbiome, inflammation, and nutritional status in gastrointestinal cancers, emphasizing potential therapeutic strategies to improve patient outcomes.