The utility of fluorodeoxyglucose positron emission tomography in the evaluation of carcinoid tumors presenting as pulmonary nodules.
BACKGROUND
Fluorodeoxyglucose positron emission tomography (FDG-PET) is sensitive for detection of neoplastic solitary pulmonary nodules but may have decreased sensitivity for detection of carcinoid tumors. Our purpose was to determine the sensitivity of FDG-PET to detect pulmonary carcinoid tumors.


METHODS
We performed a retrospective review of our institutional results regarding FDG-PET in the setting of thoracic carcinoid neoplasms. We identified 16 patients with a pathologic diagnosis of bronchial carcinoid who had an antecedent FDG-PET (from 2000 to 2004). All patients but one presented with pulmonary nodule(s).


RESULTS
Sixteen patients had a diagnosis of carcinoid tumor, typical in 11 patients and atypical in 5 patients. The mean greatest pathologic dimension was 2.08 cm (range, 1.0 to 8.3 cm). Overall positron emission tomography (PET) sensitivity was 75% (12 true-positive and 4 false-negative results). The mean (+/- SD) size of carcinoids with false-negative PET results was not significantly different from carcinoids with true-positive results (1.6 +/- 0.81 cm and 2.35 +/- 1.87 cm, p = 0.54). Fifteen of 16 patients were staged pathologically, and positive nodes were found in 2 of these patients. PET lymph node staging agreed with pathologic staging in one stage 4 patient with positive lymph nodes and distant metastasis, but PET results were false negative in the other patient who had N2 with micrometastatic disease; stage IIIA.


CONCLUSIONS
FDG-PET imaging is useful for evaluation of typical and atypical thoracic carcinoid tumors. Although overall PET sensitivity for detection of carcinoid tumors is somewhat reduced as compared to non-small cell lung cancer, it is much higher than prior reports suggest.
Daniels
Craig E
CE
Division of Pulmonary and Critical Care Medicine, Desk East 18, Mayo Clinic, 200 First St SW, Rochester, MN 55905, USA. daniels.craig@mayo.edu
Lowe
Val J
VJ
Aubry
Marie-Christine
MC
Allen
Mark S
MS
Jett
James R
JR
D000328:Adult; D000368:Aged; D001706:Biopsy; D002276:Carcinoid Tumor / Q000000981:diagnostic imaging* / Q000473:pathology; D002289:Carcinoma, Non-Small-Cell Lung / Q000000981:diagnostic imaging* / Q000473:pathology; D005260:Female; D019788:Fluorodeoxyglucose F18; D006801:Humans; D008175:Lung Neoplasms / Q000000981:diagnostic imaging* / Q000473:pathology; D008297:Male; D008875:Middle Aged; D009367:Neoplasm Staging; D049268:Positron-Emission Tomography; D019275:Radiopharmaceuticals; D012189:Retrospective Studies; D012680:Sensitivity and Specificity; D003074:Solitary Pulmonary Nodule / Q000000981:diagnostic imaging* / Q000473:pathology
D019275:Radiopharmaceuticals; D019788:Fluorodeoxyglucose F18