title: Primary salivary gland-type lung cancer: imaging and clinical predictors of outcome.
abstract: OBJECTIVE
  The objective of our study was to assess whether CT features and FDG up-take of primary salivary gland-type tumors of the lung are associated with tumor type, disease stage, or survival.
  
  
  METHODS
  CT (n = 30) and PET (n = 15) data of 30 consecutive patients with primary salivary gland-type tumors of the lung were retrospectively evaluated for tumor size, location, and homogeneity and the presence of lymphadenopathy, pleural effusions, and metastases. Maximum FDG uptake and volumetric FDG uptake of the tumors were recorded. The Wilcoxon rank sum and Fisher exact tests and univariate Cox regression were used for statistical calculations.
  
  
  RESULTS
  Compared with mucoepidermoid carcinomas, adenoid cystic carcinomas (57%) were larger (mean, 3.5 vs 2.2 cm, respectively; p = 0.03), more frequently involved the central airways (94% vs 63%; p = 0.002), and had a higher median FDG uptake (p = 0.0264). Higher FDG uptake of the primary tumor was associated with nodal tumor involvement (p = 0.05). The median overall survival times for patients with adenoid cystic carcinoma and mucoepidermoid carcinoma were 7.7 and 4.0 years, respectively. Imaging features that significantly affected overall survival included the presence of mediastinal or hilar lymphadenopathy (hazard ratio [HR], 4.33; 95% CI, 1.15-16.26; p = 0.03), suspected metastatic disease (HR, 5.10; 95% CI, 1.27-20.47; p = 0.02), and primary tumor heterogeneity (HR, 3.46; 95% CI, 1.04-11.55; p = 0.04).
  
  
  CONCLUSIONS
  Higher FDG uptake is associated with nodal disease in patients with primary salivary gland-type tumors of the lung but is not predictive of survival, whereas CT features suggestive of advanced disease correlate with worse outcome.
authors.affiliation: Department of Radiology, National Cancer Institute, Cairo, Egypt.
authors.forename: Amr
authors.initials: A
authors.lastname: Elnayal
authors.forename: Cesar A
authors.initials: CA
authors.lastname: Moran
authors.forename: Patricia S
authors.initials: PS
authors.lastname: Fox
authors.forename: Osama
authors.initials: O
authors.lastname: Mawlawi
authors.forename: Stephen G
authors.initials: SG
authors.lastname: Swisher
authors.forename: Edith M
authors.initials: EM
authors.lastname: Marom
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D005260:Female; D019788:Fluorodeoxyglucose F18; D006801:Humans; D008175:Lung Neoplasms / Q000000981:diagnostic imaging* / Q000556:secondary*; D008297:Male; D008875:Middle Aged; D009367:Neoplasm Staging; D049268:Positron-Emission Tomography / Q000379:methods*; D016016:Proportional Hazards Models; D019275:Radiopharmaceuticals; D012189:Retrospective Studies; D012468:Salivary Gland Neoplasms / Q000473:pathology*; D018709:Statistics, Nonparametric; D015996:Survival Rate; D014057:Tomography, X-Ray Computed / Q000379:methods*
chemical_list: D019275:Radiopharmaceuticals; D019788:Fluorodeoxyglucose F18