P374 - CHARACTERIZATION OF PLASMA AMINO ACID ALTERATIONS IN HEAD AND NECK CANCER: A POTENTIAL BIOMARKER STUDY

P374

CHARACTERIZATION OF PLASMA AMINO ACID ALTERATIONS IN HEAD AND NECK CANCER: A POTENTIAL BIOMARKER STUDY

T. Tsujimoto^1,*, M. Wasa², A. Sasaki³, K. Tsuneishi¹, H. Inohara⁴, T. Ito⁵

¹Department of Clinical Pharmacy, Faculty of Pharmaceutical Sciences, Kobe Gakuin University, Kobe, ²Graduate School of Medical Safety Management, Jikei University of Health Care Sciences. , Osaka, ³Department of Pharmacy, Himeji St. Mary's Hospital, Himeji, ⁴Department of Otorhinolaryngology-Head and Neck Surgery, Osaka University Graduate School of Medicine, ⁵ Osaka Center for Cancer & Cardiovascular Disease Prevention, Osaka, Japan

Rationale: Amino acid balance, crucial for homeostasis, is altered in cancer. Plasma free amino acid (PFAA) profiling aids the early detection of cancer, but research on head and neck cancer (HNC) is lacking. This study aimed to characterize PFAA profiles in HNC patients.

Methods: Forty-nine untreated new patients diagnosed with HNC and treated with chemoradiotherapy (CRT) at the Department of Otorhinolaryngology and Head and Neck Surgery, Osaka University Hospital between May 2010 and June 2013 were enrolled. Patients participated in a clinical trial investigating the efficacy of glutamine for mucositis and received glutamine (G, n=25) or placebo (P, n=24). Primary endpoint: pre-treatment PFAA vs. standard values in all patients. Secondary endpoints: PFAA changes during CRT in P vs. standard value, and PFAA differences between G and P during CRT, analyzed by one-sample proportionality and Mann-Whitney U tests. Standard values from SRL, Inc. (Tokyo, Japan) were used.

Results: The cohort (43 males, 6 females; median age 65) showed pre-treatment elevations in aspartate, cystine, glutamate, and lysine (p<0.05), and reductions in asparagine and methionine (p<0.05) vs. standard values. During CRT, cystine remained elevated at all time points (Week 2 [20 Gy], Week 4 [40 Gy], and end of CRT [66-70 Gy]) (p<0.001), and asparagine remained reduced (p<0.001) at all time points. Other amino acids and G and P PFAA differences were non-significant.

Conclusion: Pre-treatment PFAA profiles in HNC were characterized by elevated cystine and reduced asparagine, suggesting their potential as an indicator for HNC evaluation. Glutamine supplementation did not alter PFAA profiles.

Disclosure of Interest: None declared