PriMera Scientific Medicine and Public Health (ISSN: 2833-5627)

Review Article

Volume 9 Issue 5

A Discussion on the Relationship of the Gut Microbiome with Primary Tumor Location, Arginase-1 and Tumor Associated Neutrophils in Colorectal Cancer

Nicola Sarandria*

November 11, 2026

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Abstract

Colorectal cancer is one of the most common malignant cancers in the world with worrying epidemiological data both in terms of occurrence and demographics, with an ever lower age at diagnosis. In the last decade, an ever increasing focus has been put on the tumor microenvironment and the effect of the microbiome on tumor etiopathogenesis and progression. This paper proposes a focused perspective based on a defined conceptual framework describing how the microbiome's different composition along the gut segments interacts with primary tumor location, perineural invasion, Arginase-1, and tumor associated neutrophils (TANs). This discussion will go in parallel with addressing the impact of these aforementioned players on the clinical outcome of the disease and the embryological, vascular, molecular, and immunological differences influencing tumor sidedness and microbiome-related mechanisms. The importance of such perspective is to aid in the development of new therapies by understanding these underlying targetable mechanisms.

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