Toshimitsu Ohashi1, Kousuke Terasawa2, Mitsuhiro Aoki2, Takashi Akazawa3, Hirofumi Shibata2, Bunya Kuze2, Takahiko Asano4, Hiroki Kato4, Tatsuhiko Miyazaki5, Masayuki Matsuo4, Norimitsu Inoue6, Yatsuji Ito2. 1. Department of Otolaryngology, Gifu University Graduate School of Medicine, Yanagido, Gifu, Gifu 501-1194, Japan. Electronic address: tohashi@gifu-u.ac.jp. 2. Department of Otolaryngology, Gifu University Graduate School of Medicine, Yanagido, Gifu, Gifu 501-1194, Japan. 3. Department of Tumor Immunology, Osaka International Cancer Institute, 3-1-69 Otemae, Chuo-ku, Osaka 541-8567, Japan. 4. Department of Radiology, Gifu University Graduate School of Medicine, Gifu, Japan. 5. Department of Pathology, Gifu University Hospital, Gifu, Japan. 6. Department of Tumor Immunology, Osaka International Cancer Institute, 3-1-69 Otemae, Chuo-ku, Osaka 541-8567, Japan; Department of Molecular Genetics, Wakayama Medical University, 811-1 Kimiidera, Wakayama 641-8509, Japan. Electronic address: inoue-no@wakayama-med.ac.jp.
Abstract
OBJECTIVE: Cancer cells secrete large amounts of lactic acid via aerobic glycolysis. We have shown that lactic acid plays an important role as a proinflammatory and immunosuppressive mediator and promotes tumor progression. Fluorine-18 fluorodeoxyglucose (FDG) uptake detected by positron emission tomography/computed tomography (PET/CT) is considered as a good indicator of aerobic glycolysis in cancer. In this study, we examined the relationships between systemic inflammatory parameters and FDG-PET/CT parameters in advanced head and neck squamous cell carcinoma (HNSCC). Furthermore, we investigated the relationships between FDG-PET/CT parameters and M2-macrophage polarization in HNSCC by assessing the ratio of CD163, a M2-macrophage marker, to CD68, a pan-macrophage marker. METHODS: This study included 73 advanced HNSCC patients. We assessed the C-reactive protein (CRP) level, white blood cell (WBC) count, neutrophil count, lymphocyte count, and monocyte count as systemic inflammatory markers. Additionally, we assessed the maximum standardized uptake value (SUVmax), mean SUV (SUVmean), metabolic tumor volume (MTV), and total lesion glycolysis (TLG) as FDG-PET/CT parameters. RESULTS: The CRP level, WBC count, and neutrophil count were correlated with whole-body FDG-PET/CT parameters. The CD163/CD68 ratio was correlated with SUVmax and SUVmean. Our results suggest that systemic inflammation, which is associated with neutrophils, develops in patients with HNSCC having tumors with a larger volume and increased glucose uptake and that M2-macrophage polarization is promoted in HNSCC with increased glucose uptake, SUVmax, and SUVmean. FDG-PET/CT has the potential to reflect cancer-related chronic inflammation and immunosuppressive conditions in cancer patients. CONCLUSIONS: FDG-PET/CT parameters appear to be useful in assessing the immune status in HNSCC.
OBJECTIVE:Cancer cells secrete large amounts of lactic acid via aerobic glycolysis. We have shown that lactic acid plays an important role as a proinflammatory and immunosuppressive mediator and promotes tumor progression. Fluorine-18 fluorodeoxyglucose (FDG) uptake detected by positron emission tomography/computed tomography (PET/CT) is considered as a good indicator of aerobic glycolysis in cancer. In this study, we examined the relationships between systemic inflammatory parameters and FDG-PET/CT parameters in advanced head and neck squamous cell carcinoma (HNSCC). Furthermore, we investigated the relationships between FDG-PET/CT parameters and M2-macrophage polarization in HNSCC by assessing the ratio of CD163, a M2-macrophage marker, to CD68, a pan-macrophage marker. METHODS: This study included 73 advanced HNSCCpatients. We assessed the C-reactive protein (CRP) level, white blood cell (WBC) count, neutrophil count, lymphocyte count, and monocyte count as systemic inflammatory markers. Additionally, we assessed the maximum standardized uptake value (SUVmax), mean SUV (SUVmean), metabolic tumor volume (MTV), and total lesion glycolysis (TLG) as FDG-PET/CT parameters. RESULTS: The CRP level, WBC count, and neutrophil count were correlated with whole-body FDG-PET/CT parameters. The CD163/CD68 ratio was correlated with SUVmax and SUVmean. Our results suggest that systemic inflammation, which is associated with neutrophils, develops in patients with HNSCC having tumors with a larger volume and increased glucose uptake and that M2-macrophage polarization is promoted in HNSCC with increased glucose uptake, SUVmax, and SUVmean. FDG-PET/CT has the potential to reflect cancer-related chronic inflammation and immunosuppressive conditions in cancerpatients. CONCLUSIONS:FDG-PET/CT parameters appear to be useful in assessing the immune status in HNSCC.