Tournoy 2007.

Study characteristics
Patient sampling	Prospective consecutive (?) Patient series
Patient characteristics and setting	52 participants, median age = 68 (range = 48 to 80) years, 39 males/13 females, Belgium Histology of primary tumour Adenocarcinoma: N = 17; squamous cell: N = 20; large cell: N = 10; adenosquamous: N = 5; comorbidities: not reported Inclusion criteria Consecutive participants with suspected or pathologically proven primary NSCLC were eligible if a tissue specimen from at least 1 of the intrathoracic lymph nodes was available and if they underwent an integrated FDG PET‐CT scan Exclusion criteria None listed Previous tests CT Clinical setting Hospital department of respiratory medicine It is unclear if the inclusion criteria narrow the range of patients who would receive PET‐CT in practice, namely, patients (clinically) with suspected resectable non‐small cell lung cancer, a proportion of whom would have N2 or N3 disease already on PET‐CT
Index tests	Participants fasted for at least 6 hours, after which blood glucose levels were determined to ascertain a level of < 200 mg/dl. Participants then received 4 MBq/kg FDG intravenously followed by 250 ml sodium chloride and 20 mg furosemide. Image acquisition started 60 min after injection of FDG in a relaxed supine position with the arms alongside the body using an integrated FDG PET‐CT scanner (Philips Gemini FDG PET‐CT, Philips Medical Systems, Cleveland, OH, USA). First, a total body low‐dose CT scan for calculation of the attenuation correction was performed (120 kV, effective tube current‐time product maximum 30 mAS, pitch 0.9, collimation 1661.5 mm, rotation time 0.5 s, reconstructed contiguous slices of 5 mm, scan field from head up to the upper tights). Second, a scan was performed with a dual head injector (175 mAS, otherwise the same scan parameters) after intravenous injection of 120 ml contrast medium with an iodine concentration of 300 mg/ml at a flow rate of 1.8 ml/s followed by a saline flush. No oral contrast was administered. Next, the FDG PET scan from the orbitomeatal region up to the upper tights (consisting of 8 to 9 bed positions of 3 min per table position) was performed. The CT and integrated FDG PET‐CT scans represented a single procedure of data acquisition but were read separately. For the CT analysis, the radiologist was blinded to the FDG PET data. All intrathoracic lymph nodes were noted and the small and long axes were measured (mm). A lymph node with a short axis of at least 10 mm was indicated as suspect. The FDG PET‐CT scan was interpreted based on both CT and FDG PET images, which were read by a nuclear physician and a radiologist. The maximum and mean SUV values were determined by drawing regions of interest on the attenuation‐corrected PET fusion images around the primary tumour or the involved lymph node. The variables SUVmax and SUVmean were then calculated as the maximum and mean SUV values, respectively, within the region of interest. Quantitative evaluation based on the SUVmax/SUVliver ratio was calculated as the ratio of the SUVmax over the mean SUV value obtained from the homogenous distribution of radioactivity in the liver. The ultimate rating of positive/negative per‐patient result "is based on the visual correlation by the nuclear physician" Covariates Type of PET‐CT scanner: integrated FDG PET‐CT scanner (Philips Gemini FDG PET‐CT; Philips Medical Systems, Cleveland, OH, USA) FDG dose: 4 MBq/kg FDG intravenously followed by 250 ml sodium chloride and 20 mg furosemide Injection‐to‐scan time: 60 min Attenuation correction: yes Cut‐off values for test positivity (malignancy): The ultimate rating of positive/negative per‐patient result "is based on the visual correlation by the nuclear physician"
Target condition and reference standard(s)	For intrathoracic lymph nodes, a tissue sample was obtained either by mediastinoscopy, surgical resection, or by linear endoscopic ultrasound. The latter consisted of either oesophageal endoscopic ultrasound with real‐time guided fine needle aspiration (EUS‐FNA) or endobronchial endoscopic ultrasound with real‐time guided transbronchial needle aspiration (EBUS‐TBNA). Because the negative predictive values of EUS‐FNA and EBUS‐TBNA were considered too low, surgical confirmation was always done in case no malignant lymph node invasion could be demonstrated by either of these endoscopic techniques
Flow and timing	Data were available for 48/52 participants because for 2/52 participants, no pathologically confirmed mediastinal data were available (only hilar), and for 2/52 participants, the central location of the primary tumour precluded a confident discrimination of mediastinal nodes
Comparative
Notes	Per‐patient data provided by an author via email communication The study received no funding Adverse events: not reported
Methodological quality
Item	Authors' judgement	Risk of bias	Applicability concerns
DOMAIN 1: Patient Selection
Was a consecutive or random sample of patients enrolled?	Unclear
Was a case‐control design avoided?	Yes
Did the study avoid inappropriate exclusions?	Unclear
		Unclear	Unclear
DOMAIN 2: Index Test All tests
Were the index test results interpreted without knowledge of the results of the reference standard?	Yes
Was there a pre‐specified cut‐off value?	No
Was a positive result defined?	Unclear
		Unclear	Low
DOMAIN 3: Reference Standard
Is the reference standards likely to correctly classify the target condition?	Yes
Were the reference standard results interpreted without knowledge of the results of the index tests?	Unclear
		Low	Low
DOMAIN 4: Flow and Timing
Was there an appropriate interval between index test and reference standard?	Yes
Did all patients receive the same reference standard?	Yes
Were all patients included in the analysis?	No
		Unclear