Correlation between hematological parameters and PET/CT metabolic parameters in patients with head and neck cancer.

BACKGROUND: Systemic inflammation is predictive of the overall survival in cancer patients and is related to the density of immune cells in the tumor microenvironment of cancer, which in turn correlates with 18F -fluorodeoxyglucose (FDG)-positron emission tomography/computed tomography (PET/CT) metabolic parameters (MPs). The density of tumor-infiltrating lymphocytes (TILs) in the microenvironment has the potential to be a biomarker that can be used clinically to optimize patient selection in oropharyngeal head and neck squamous cell carcinoma (HNSCC). There is little to no data regarding the association of systemic inflammation with PET/CT-MPs, especially in HNSCC. This study aimed to evaluate the correlation between markers of host inflammation, namely blood neutrophil-to-lymphocyte ratio (NLR) and platelet-to-lymphocyte ratio (PLR), with the PET/CT-MPs standardized uptake value (SUV), metabolic tumor volume (MTV), and total lesion glycolysis (TLG) of the primary tumor, derived from FDG-PET/CT in patients with nonmetastatic (cM0) HNSCC before treatment. We hypothesized that NLR and PLR at baseline are positively correlated with PET/CT-MPs. METHODS: A retrospective review of consecutive patients with HNSCC with a pretreatment PET/CT was performed. NLR and PLR were computed using complete blood counts measured within 10 days before the start of any treatment. The correlation between NLR and PLR with PET/CT-MPs was evaluated with Spearman's rho test. RESULTS: Seventy-one patients were analyzed. Overall survival (OS) at 1, 2, and 3 years was 86%, 76%, and 68%. PLR was found to be correlated with MTV (rho = 0.26, P = .03) and TLG (rho = 0.28, P = .02) but not with maximum SUV or mean SUV. There was no correlation between NLR and the analyzed PET/CT-MPs. TLG was associated with worse survival in uni- and multivariable analysis, but no other PET/CT-MPs were associated with either OS or disease-specific survival (DSS). NLR and PLR were associated with OS and DSS on uni- and multivariable analysis. CONCLUSIONS: In patients with HNSCC before any treatment such as definitive radio (chemo)therapy or oncologic surgery followed by adjuvant RT, baseline PLR correlated with MTV and TLG but not with SUV. NLR was not correlated with any PET/CT-MPs analyzed in our study. Confirmatory studies are needed, and a potential interaction between tumor microenvironment, host inflammation, and FDG-PET/CT measures warrants further investigation.

Hemoglobin vesicles improve wound healing and tissue survival in critically ischemic skin in mice.

Local hypoxia, as due to trauma, surgery, or arterial occlusive disease, may severely jeopardize the survival of the affected tissue and its wound-healing capacity. Initially developed to replace blood transfusions, artificial oxygen carriers have emerged as oxygen therapeutics in such conditions. The aim of this study was to target primary wound healing and survival in critically ischemic skin by the systemic application of left-shifted liposomal hemoglobin vesicles (HbVs). This was tested in bilateral, cranially based dorsal skin flaps in mice treated with a HbV solution with an oxygen affinity that was increased to a P(50) (partial oxygen tension at which the hemoglobin becomes 50% saturated with oxygen) of 9 mmHg. Twenty percent of the total blood volume of the HbV solution was injected immediately and 24 h after surgery. On the first postoperative day, oxygen saturation in the critically ischemic middle flap portions was increased from 23% (untreated control) to 39% in the HbV-treated animals (P < 0.05). Six days postoperatively, flap tissue survival was increased from 33% (control) to 57% (P < 0.01) and primary healing of the ischemic wound margins from 6.6 to 12.7 mm (P < 0.05) after HbV injection. In addition, higher capillary counts and endothelial nitric oxide synthase expression (both P < 0.01) were found in the immunostained flap tissue. We conclude that left-shifted HbVs may ameliorate the survival and primary wound healing in critically ischemic skin, possibly mediated by endothelial nitric oxide synthase-induced neovascularization.

Hemoglobin vesicles reduce hypoxia-related inflammation in critically ischemic hamster flap tissue.

OBJECTIVES: The aim of this study was to investigate the effect of a highly viscous, left-shifted hemoglobin vesicle solution (HbV) on the hypoxia-related inflammation and the microcirculation in critically ischemic peripheral tissue. DESIGN: Randomized prospective study. SETTING: University laboratory. SUBJECTS: Twenty-four male golden Syrian hamsters. INTERVENTIONS: Island flaps were dissected from the back skin of anesthetized hamsters for assessment with intravital microscopy. The flap included a critically ischemic, hypoxic area that was perfused via a collateralized vasculature. One hour after completion of the preparation, the animals received an injection of 25% of total blood volume of 0.9% NaCl or NaCl suspended with HbVs at a concentration of 5 g/dL (HbV5) or 10 g/dL (HbV10). MEASUREMENTS AND MAIN RESULTS: Plasma viscosity was increased from 1.32 cP to 1.61 cP and 2.14 cP after the administration of HbV5 and HbV10, respectively (both p < .01). Both HbV solutions raised partial oxygen tension (Clark-type microprobes) in the ischemic tissue from approximately 10 torr to 17 torr (p < .01), which was paralleled by an increase in capillary perfusion by > 200% (p < .01). The 50% increase in macromolecular capillary leakage found over time in the control animals was completely abolished by the HbV solutions (p < .01), which was accompanied by a > 50% (p < .01) reduction in cells immunohistochemically stained for tumor necrosis factor-alpha and interleukin-6 and in leukocyte counts, whereas no such changes were observed in the anatomically perfused, normoxic tissue. CONCLUSIONS: Our study suggests that in critically ischemic, hypoxic peripheral tissue, hypoxia-related inflammation may be reduced by a top-load infusion of HbV solutions. We attributed this effect to a restoration of tissue oxygenation and an increase in plasma viscosity, both of which may have resulted in attenuation of secondary microcirculatory impairments.