title: Noninvasive assessment of tumor microenvironment using dynamic contrast-enhanced magnetic resonance imaging and 18F-fluoromisonidazole positron emission tomography imaging in neck nodal metastases.
abstract: OBJECTIVE
  To assess noninvasively the tumor microenvironment of neck nodal metastases in patients with head-and-neck cancer by investigating the relationship between tumor perfusion measured using dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI) and hypoxia measured by (18)F-fluoromisonidazole ((18)F-FMISO) positron emission tomography (PET).
  
  
  METHODS
  Thirteen newly diagnosed head-and-neck cancer patients with metastatic neck nodes underwent DCE-MRI and (18)F-FMISO PET imaging before chemotherapy and radiotherapy. The matched regions of interests from both modalities were analyzed. To examine the correlations between DCE-MRI parameters and standard uptake value (SUV) measurements from (18)F-FMISO PET, the nonparametric Spearman correlation coefficient was calculated. Furthermore, DCE-MRI parameters were compared between nodes with (18)F-FMISO uptake and nodes with no (18)F-FMISO uptake using Mann-Whitney U tests.
  
  
  RESULTS
  For the 13 patients, a total of 18 nodes were analyzed. The nodal size strongly correlated with the (18)F-FMISO SUV (rho = 0.74, p < 0.001). There was a strong negative correlation between the median k(ep) (redistribution rate constant) value (rho = -0.58, p = 0.042) and the (18)F-FMISO SUV. Hypoxic nodes (moderate to severe (18)F-FMISO uptake) had significantly lower median K(trans) (volume transfer constant) (p = 0.049) and median k(ep) (p = 0.027) values than did nonhypoxic nodes (no (18)F-FMISO uptake).
  
  
  CONCLUSIONS
  This initial evaluation of the preliminary results support the hypothesis that in metastatic neck lymph nodes, hypoxic nodes are poorly perfused (i.e., have significantly lower K(trans) and k(ep) values) compared with nonhypoxic nodes.
authors.affiliation: Department of Medical Physics, Memorial Sloan-Kettering Cancer Center, New York, NY 10065, USA.
authors.forename: Jacobus F A
authors.initials: JF
authors.lastname: Jansen
authors.forename: Heiko
authors.initials: H
authors.lastname: Schöder
authors.forename: Nancy Y
authors.initials: NY
authors.lastname: Lee
authors.forename: Ya
authors.initials: Y
authors.lastname: Wang
authors.forename: David G
authors.initials: DG
authors.lastname: Pfister
authors.forename: Matthew G
authors.initials: MG
authors.lastname: Fury
authors.forename: Hilda E
authors.initials: HE
authors.lastname: Stambuk
authors.forename: John L
authors.initials: JL
authors.lastname: Humm
authors.forename: Jason A
authors.initials: JA
authors.lastname: Koutcher
authors.forename: Amita
authors.initials: A
authors.lastname: Shukla-Dave
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D002294:Carcinoma, Squamous Cell / Q000000981:diagnostic imaging / Q000378:metabolism / Q000473:pathology; D015687:Cell Hypoxia / Q000502:physiology; D005260:Female; D006258:Head and Neck Neoplasms / Q000000981:diagnostic imaging / Q000378:metabolism / Q000473:pathology; D006801:Humans; D008198:Lymph Nodes / Q000000981:diagnostic imaging / Q000378:metabolism / Q000473:pathology; D008207:Lymphatic Metastasis; D008279:Magnetic Resonance Imaging / Q000379:methods*; D008297:Male; D008875:Middle Aged; D008920:Misonidazole / Q000031:analogs & derivatives / Q000493:pharmacokinetics; D049268:Positron-Emission Tomography / Q000379:methods*; D019275:Radiopharmaceuticals / Q000493:pharmacokinetics; D012189:Retrospective Studies; D018709:Statistics, Nonparametric
chemical_list: D019275:Radiopharmaceuticals; C031843:fluoromisonidazole; D008920:Misonidazole