Integrated imaging of non-small cell lung cancer recurrence: CT and PET-CT findings, possible pitfalls and risk of recurrence criteria.

Abstract

To review the role of imaging in the diagnosis of recurrent disease in previously treated non-small cell lung cancer (NSCLC) and discuss the imaging pitfalls. A comprehensive review of published literature on CT and PET imaging of NSCLC recurrence was performed. Diagnostic and prognostic values are discussed. Representative imaging examples are illustrated. Up to 30% of NSCLC recurrences present as loco-regional, involving treated hemithorax and ipsilateral lymph nodes, while 70% present as metachronous distant metastases. CT and PET-CT play an important role in the early detection of recurrence; indications for imaging vary depending on pathological features. Imaging plays a central role in the identification of recurrence and may predict prognosis. Lung cancer recurs after surgery in 30% to 75% of patients. CT and PET-CT are crucial in identification of loco-regional recurrence. Knowledge of potential pitfalls is essential, especially for parenchymal or nodal recurrence. CT can diagnose metastases but further examinations (PET-CT, MRI) are often needed. Morphological and functional imaging criteria may help in predicting recurrence.