Immunomodulatory and Immunonutritional Effects of a Standardized Extract of Cultured Lentinula edodes Mycelia in Cancer: From Prevention to Perioperative Microenvironment Stabilization

A standardized extract of cultured Lentinula edodes mycelia (ECLM), commercially known as AHCC®, shows anti-inflammatory, immunomodulatory, and organ-protective properties. Experimental studies have indicated that ECLM modulates innate and adaptive immunity, including natural killer (NK) cell activity, antigen-presenting cell function, T-cell responses, and cytokine balance. These effects are particularly relevant in oncology because surgical stress and ischemia–reperfusion injury (IRI) generate a transient perioperative environment characterized by immune suppression, inflammation, and conditions favorable for metastatic progression. Recent animal studies have demonstrated the protective effects of ECLM in intestinal and hepatic IRI models, providing a potential mechanistic rationale for improving the perioperative host microenvironment. Clinical studies on hepatocellular carcinoma, pancreatic cancer, and gynecological malignancies suggest that ECLM may offer potential benefits in immune preservation, nutritional support, symptom management, and recurrence prevention, although most studies are small and hypothesis-generating. Emerging evidence from patient-derived xenograft and spontaneous carcinogenesis models further suggests that ECLM may influence tumor biology beyond host immune activation, although the underlying mechanisms require elucidation. This review summarizes the mechanistic, preclinical, translational, and clinical evidence supporting the use of ECLM as a candidate for perioperative immunonutritional strategies. We propose the hypothesis that ECLM may function as a perioperative microenvironmental stabilizer that integrates immune preservation and intestinal barrier protection.