PET-CT in the assessment of lung cancer at Rikshospitalet from 2007-2011.

BACKGROUND: PET-CT is an aid in the assessment of lung cancer for identifying operable patients. The examination is recommended for most patients with non-small cell lung cancer whom the primary assessment has indicated may have a curable disease. The aim was to assess the usefulness of PET-CT for patients assumed to be operable who underwent an examination at Rikshospitalet. MATERIAL AND METHOD: Patients admitted for lung cancer assessment are registered consecutively in the department's quality database. We analysed data for the period 2007-2011 for patients whom a primary assessment had revealed to have a potentially operable tumour. For capacity reasons, some patients underwent surgery without a prior PET-CT. RESULTS: Of 651 potentially operable patients, 533 had had a PET-CT scan of which 403 (76%) had undergone surgery. We calculated that the examination had a sensitivity of 78% (95% CI 70-86) and specificity 88% (95% CI 85-91%), positive predictive value 64% (95% CI 55-72) and negative predictive value 94% (95% CI 91-96) for spreading to mediastinal lymph nodes. Diagnostic accuracy was 86% (95% CI 83-89) with kappa agreement 0.61 (95% CI 0.53-0.69) between PET-CT and actual findings of malignant or benign mediastinal lymph nodes. INTERPRETATION: PET-CT was a useful tool for selecting potentially operable lung cancer patients at Rikshospitalet in the period 2007-2011. Provided that the population we scan with PET-CT does not change, patients with a negative PET-CT can with few exceptions be referred directly for surgery without further invasive assessment.