There are hereditary mutations that predispose individuals to cancer development, such as pathogenic variants in the germ line of the tumor protein 53 (TP53) suppressor gene. This leads to a rare condition known as Li–Fraumeni syndrome (LFS), characterized by a high risk of developing multiple cancers throughout life by the precancerous niche that promotes the tumor microenvironment. LFS presents a significant challenge due to its limited therapeutic and chemoprophylactic options. Recently, protocols involving metformin as a prophylactic medication have been developed to target precancerous niches. However, this approach is still in the clinical phase, and no established therapeutic regimen is available. Therefore, new alternatives are needed to impact this disease effectively. Novel studies suggest that Sechium extract, rich in polyphenols, exhibits chemoprophylactic, antineoplastic, anti-inflammatory, and antioxidant activities, all involved in the tumor microenvironment of LFS. However, the specific role of Sechium extract in preventing recurrent neoplastic development in LFS remains unclear. We conducted this research through a case report of an LFS-diagnosed patient who has experienced multiple malignancies and cutaneous neoformations. This patient received a chemoprophylactic supplementation based on Sechium H387 07 extract over 11 years without reporting new primary malignancy events or recurrences, as evidenced by laboratory and positron emission tomography/computed tomography (PET/CT) studies. An extensive literature review on the disease, precancerous niche, tumor microenvironment, and potential mechanisms of Sechium H387 07 extract components was conducted to explain cancer absence in LFS. This review promotes the research and use of polyphenols as powerful chemoprophylactic agents to prevent and treat proliferative diseases like LFS.
