Background and Objective: Although accounting for a relatively small proportion of all lung
cancers, small cell lung cancer (SCLC) remains to be a global health concern with grim prognosis. Radiotherapy
(RT) plays a central role in SCLC management either as a curative or palliative therapeutic strategy.
There has been considerable progress in RT of SCLC, thanks to improved imaging techniques leading
to accurate target localization for precise delivery of RT. Positron emission tomography (PET) is increasingly
used in oncology practice as a non-invasive molecular imaging modality.
Methods: Herein, we review the utility of molecular imaging with 2-deoxy-2-[fluorine-18] fluoro-Dglucose
PET (18F-FDG PET) for SCLC from a radiation oncology perspective.
Results: There has been extensive research on the utility of PET for SCLC in terms of improved staging,
restaging, treatment designation, patient selection for curative/palliative intent, target localization,
response assessment, detection of residual/recurrent disease, and prediction of treatment outcomes.
Conclusion: PET provides useful functional information as a non-invasive molecular imaging modality
and may be exploited to improve the management of patients with SCLC. Incorporation of PET/CT in
staging of patients with SCLC may aid in optimal treatment allocation for an improved therapeutic ratio.
From a radiation oncology perspective, combination of functional and anatomical data provided by
integrated PET/CT improves discrimination between atelectasis and tumor, and assists in the
designation of RT portals with its high accuracy to detect intrathoracic tumor and nodal disease. Utility
of molecular imaging for SCLC should be further investigated in prospective randomized trials to acquire
a higher level of evidence for future potential applications of PET.