Extranodal malignant lymphoma: detection with FDG PET versus CT

Radiology. 1998 Feb;206(2):475-81. doi: 10.1148/radiology.206.2.9457202.


Purpose: To evaluate use of functional imaging with positron emission tomography (PET) versus computed tomography (CT) for detection of extranodal lymphoma spread.

Materials and methods: Eighty-one consecutive and previously untreated patients with malignant non-Hodgkin lymphoma (n = 43) or Hodgkin disease (n = 38) were examined with 2-[fluorine-18]fluoro-2-deoxy-D-glucose (FDG) PET and contrast material-enhanced CT. Concordant findings at both CT and FDG PET were regarded as actual locations of disease; discordant results were resolved on the basis of biopsy or follow-up results when possible.

Results: Forty-two lesions were identified at both PET and CT, and 19 were verified with biopsy results. PET demonstrated a further 24 lesions. Verification was possible in 15 of these lesions with biopsy (n = 10), magnetic resonance imaging (n = 1), scintigraphic (n = 1), or follow-up (n = 3) results. In 14 of these 15 lesions, PET findings were confirmed (bone marrow, nine; spleen, three; other, two). Seven lesions not visualized at FDG PET were identified at CT, six of which were verified with biopsy (n = 2) or follow-up (n = 4) results. Five of these six CT findings were found to be erroneous. In 13 patients, PET findings led to changes in tumor staging.

Conclusion: PET may provide more information about extranodal lymphoma than does incremental CT.

Publication types

  • Comparative Study

MeSH terms

  • Adult
  • Biopsy
  • False Negative Reactions
  • False Positive Reactions
  • Female
  • Fluorine Radioisotopes*
  • Fluorodeoxyglucose F18*
  • Hodgkin Disease / diagnostic imaging*
  • Humans
  • Lymphoma, Non-Hodgkin / diagnostic imaging*
  • Male
  • Radiopharmaceuticals*
  • Tomography, Emission-Computed*
  • Tomography, X-Ray Computed*


  • Fluorine Radioisotopes
  • Radiopharmaceuticals
  • Fluorodeoxyglucose F18