Sensitive detection of mediastinal lymph node metastasis of lung cancer with 11C-choline PET.
11C-choline and FDG are PET tracers used to visualize various malignancies. In this study, we compared their capabilities in detecting mediastinal lymph node metastasis originating from non-small cell lung cancer (NSCLC).


METHODS
Twenty-nine patients with biopsy-proven NSCLC were studied with PET. 11C-choline PET and FDG PET were performed from 5 and 40 min, respectively, after injection of 370 MBq tracer. PET data were analyzed in terms of the standardized uptake value (SUV). After the PET study, the patients underwent lung resection and mediastinal lymph node dissection. The resected specimens were examined pathologically, and the PET data were analyzed in reference to the pathologic data.


RESULTS
With 11C-choline, the SUV in metastasis was similar to the SUV in the primary tumor, where the similarity of the SUV was 100% allowing for a 40% difference. With FDG, small metastases were invisible on the PET image. The SUV of FDG in metastasis was much smaller than that in the primary tumor, and the similarity of the SUV was only 19% allowing for a 40% difference. When pathologic findings were used as standards, the sensitivities of 11C-choline PET and FDG PET in detecting mediastinal lymph node metastasis were 100% and 75%, respectively.


CONCLUSIONS
11C-choline PET was very effective in detecting lymph node metastases in the mediastinum originating from NSCLC, with a sensitivity of 100%. 11C-choline PET promises to be useful not only before surgery but also after surgery.
Hara
T
T
Department of Radiology, International Medical Center of Japan, Tokyo.
Inagaki
K
K
Kosaka
N
N
Morita
T
T
D000328:Adult; D000368:Aged; D002250:Carbon Radioisotopes / Q000493:pharmacokinetics; D002289:Carcinoma, Non-Small-Cell Lung / Q000000981:diagnostic imaging* / Q000473:pathology; D002794:Choline / Q000493:pharmacokinetics; D005260:Female; D019788:Fluorodeoxyglucose F18; D006801:Humans; D007091:Image Processing, Computer-Assisted; D008175:Lung Neoplasms / Q000000981:diagnostic imaging* / Q000473:pathology*; D008197:Lymph Node Excision; D008198:Lymph Nodes / Q000000981:diagnostic imaging / Q000473:pathology; D008207:Lymphatic Metastasis / Q000000981:diagnostic imaging*; D008297:Male; D008482:Mediastinum; D008875:Middle Aged; D019047:Phantoms, Imaging; D019275:Radiopharmaceuticals; D012680:Sensitivity and Specificity; D014055:Tomography, Emission-Computed
D002250:Carbon Radioisotopes; D019275:Radiopharmaceuticals; D019788:Fluorodeoxyglucose F18; D002794:Choline