Francesco Fraioli MD, Presenter: Nothing to Disclose

Maria Vittoria Mattoli MD, Abstract Co-Author: Nothing to Disclose

Raymondo Endozo, Abstract Co-Author: Nothing to Disclose

Shonit Punwani MBBS, Abstract Co-Author: Nothing to Disclose

Ashley McAllister Groves MBBS, Abstract Co-Author: Investigator, GlaxoSmithKline plc Investigator, General Electric Company Investigator, Siemens AG

The aim of our study was to assess the diagnostic performance of simultaneous PET/MR in patients with non-small cell lung cancer.

Fifty consecutive consenting patients who underwent routine 18-fluorodeoxyglucose (FDG) PET/CT for potentially radically treatable lung cancer following staging CT were recruited for PET/MR imaging on the same day. Two experienced readers, unaware of the other modalities results, interpreted PET/MR images independently. Discordances were resolved in consensus. PET/MR TNM staging was compared to reference standard that was histopathology from thoracotomy in 33 patients. In the remaining non-surgical seventeen patients TNM was determined based on histology from biopsy, imaging results (CT and PET/CT) and follow up. ROC curve analysis was used to assess accuracy, sensitivity and specificity of the PET/MR to evaluate the surgical resectability of primary tumour. Kappa statistic was used to assess inter-observer agreement for PET MR TNM staging. Two different readers, without knowledge of the PET/MR findings, subsequently separately reviewed PET/CT images for TNM staging purpose. Generalized kappa statistic was used to determine inter-modality agreement between PET/CT and PET/MR for TNM staging.  

ROC curve analysis showed that PET/MR had a specificity of 92.3% and a sensitivity of 97.3% in the determination of resectability with an Area Under the Curve (AUC) of 0.95. Inter-observer agreement for PET MR reading was between substantial and perfect between the two readers (0.646< Cohen’s kappa < 1) for T-Stage, N-Stage and M-Stage. Inter-modality agreement between PET/CT and PET/MR was between substantial and almost perfect for T-Stage, N-Stage and M-Stage (0.627< Cohen’s kappa < 0.823).  

In lung cancer patients PET/MR appears a robust technique for preoperative staging and carries a significantly lower radiation dose.

Simultaneous PET/MR may be an alternative to PET/CT, with the benefit of reduced radiation exposure. This will need to be balanced by cost and availability constraints.

Fraioli, F, Mattoli, M, Endozo, R, Punwani, S, Groves, A, Non-small Cell Lung Cancer Resectability: Diagnostic Value of PET/MR.  Radiological Society of North America 2014 Scientific Assembly and Annual Meeting, - ,Chicago IL. http://archive.rsna.org/2014/14015447.html