1. 18F-FDGPET for Mediastinal Staging
of Lung Cancer:
Which SUV Threshold Makes Sense?
Dirk Hellwig et al.
Department of Nuclear Medicine, Saarland University Medical Center,
Homburg/Saar, Germany
J Nucl Med 2007; 48:1761–1766
Resident: Apichaya Claimon, M.D.
Advisor: Pongpija Tuchinda, M.D.
2. Evaluation of mediastinal LN involvement
Mediastinoscopy & Excision
Gold standard
Sen 80%, Spec 100%
Invasive
3. Contrast-enhanced CT & MRI
Use size criteria
to differentiate between benign & malignant
But 21% of metastases are in normal sized LN
40% of enlarged LN are no malignancy
4. 18F-FDG PET
The most accurate noninvasive modality for
staging mediastinal LN in lung cancer
5. Aim of the study
To determine optimum SUV threshold
for mediastinal LN staging in patients with
NSCLC
To compare diagnostic performance of
SUV analysis with visual interpretation
6. MATERIALS AND METHODS
Retrospective study
Patients with suspected NSCLC
18F-FDG PET
within 6 wk
Mediastinoscopy
Total 95 (75 men, 20 woman, age 62+9)
7. 18F-FDG PET LN evaluation
Visual
Compare with mediastinal blood pool
6 level (- - - to + + +)
SUV max
1.5 cm ROI
over visible LN or typical area of LN station
10. 18F-FDG PET in LN staging of lung cancer
unaffected lymph nodes (N0)
peribronchial or hilar lymph node involvement (N1)
ipsilateral mediastinal and subcarinal involvement (N2)
contralateral and supraclavicular involvement (N3)
11. Comparison of SUVmax in mediastinal LN
SUVs were higher in metastatic lymph node stations (P < 0.01)
12. Tumor-free LN with inflammatory changes
had SUV = 2.7 + 2.0
(range, 0.8–14.9; n = 146)
20. Human observation has higher sensitivity
than SUV analysis
But SUV has greater value in less
experience observer
21. SUV threshold = 2.5 is feasible
For differentiating benign from metastatic
mediastinal lymph nodes in lung CA patients
Sen = 89%, Spec = 84%
False - : small metastasis
False + : LN inflammation
22. High NPV (96%)
if PET –ve ; can omit mediastinoscopy
Highest diagnostic accuracy at SUV > 4.5
But SUV = 2.5 cannot applied to LN
metastasis in other tumor types
Because differ 18F-FDG uptake