Higher levels of glycine were associated in our patients with decreased OS and with increased risk of advanced stage, while higher serine was significantly associated with decreased OS and, with near-borderline significance, with increased risk of advanced stage.
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The sentences
The only study which specifically addressed the link between the basal serum AA levels and long-term prognosis in HNC patients concluded that increased serum levels of methionine had a favourable prognostic impact in terms of overall survival (OS) and relapse-free survival, while increased serine showed borderline significance as a negative prognostic factor for OS [ 15 ].