Myosteatosis mediates the link between specific dietary components and colorectal carcinogenesis: from PPLSS...

Area of Science:

• Nutrition Science
• Oncology
• Radiology

Background:

• Dietary components may influence colorectal carcinogenesis through ectopic fat accumulation.
• Myosteatosis, indicated by low-attenuation muscle area (LAMA) and reduced skeletal muscle density (SMD), is an underrecognized obesity phenotype.
• Ectopic fat's role in colorectal cancer (CRC) development requires further elucidation.

Purpose of the Study:

• To investigate the association between dietary intake, ectopic fat accumulation, and colorectal cancer risk.
• To determine the mediating role of ectopic fat in the relationship between diet and CRC.
• To evaluate the predictive importance of dietary and body composition variables for CRC risk.

Main Methods:

• A multi-center case-control study involving 163 CRC patients and 144 controls.
• CT-derived body composition analysis (LAMA, SMD, NAMA) and dietary intake assessment.
• Logistic regression, mediation analysis, and random forest modeling were employed.

Main Results:

• CRC patients showed significantly higher myosteatosis (68.1% vs. 31.9%).
• Diets high in animal nutrients and carbohydrates increased LAMA and visceral adiposity index (VAI) while decreasing SMD and NAMA in men.
• Low bean protein intake negatively impacted muscle parameters and increased VAI, particularly in men.

Conclusions:

• Myosteatosis is a key factor in colorectal carcinogenesis.
• Dietary patterns influence ectopic fat accumulation, which mediates CRC risk.
• Partial substitution of red meat with soy protein may mitigate CRC risk by addressing myosteatosis.