title: Skull base involvement by a nasopharyngeal carcinoma shown by Tc-99m MDP SPECT but not by computed tomography.
abstract: OBJECTIVE
  Plain radiographs, computed tomography (CT), and more recently magnetic resonance imaging (MRI) are used routinely to stage carcinoma of the nasopharynx. Tc-99m methylene diphosphonate (MDP) SPECT is seldom used for local staging of the disease.
  
  
  METHODS
  Plain radiographs and CT were used to stage squamous carcinoma of the nasopharynx in a 50-year-old man with a left XII nerve palsy.
  
  
  RESULTS
  Findings of the plain radiographs were normal, whereas the CT scan revealed a nonhomogenous hyperdense mass in the nasopharynx but intact underlying bone. Given the symptoms, a Tc-99m MDP planar scan was ordered and showed no enhanced uptake, but SPECT images obtained at the same time revealed markedly increased focal radiotracer uptake in the region of the tumor, indicating osseous involvement.
  
  
  CONCLUSIONS
  Possible bony invasion with a nasopharyngeal carcinoma may be better shown with MDP SPECT than with planar isotope bone scans, plain radiographs, or CT.
authors.affiliation: Department of Nuclear Medicine, Pakistan Institute of Engineering and Applied Sciences, Islamabad, Pakistan.
authors.forename: S
authors.initials: S
authors.lastname: Saeed
authors.forename: S
authors.initials: S
authors.lastname: Haq
authors.forename: M
authors.initials: M
authors.lastname: Sohaib
authors.forename: A N
authors.initials: AN
authors.lastname: Khan
mesh_terms: D000328:Adult; D002294:Carcinoma, Squamous Cell / Q000473:pathology*; D003389:Cranial Nerve Diseases / Q000209:etiology; D006801:Humans; D007002:Hypoglossal Nerve; D008297:Male; D009303:Nasopharyngeal Neoplasms / Q000473:pathology*; D019275:Radiopharmaceuticals; D019292:Skull Base Neoplasms / Q000000981:diagnostic imaging* / Q000556:secondary*; D013669:Technetium Tc 99m Medronate; D015899:Tomography, Emission-Computed, Single-Photon; D014057:Tomography, X-Ray Computed
chemical_list: D019275:Radiopharmaceuticals; D013669:Technetium Tc 99m Medronate