Recent progress in imaging techniques for early lung cancer diagnosis

Over many years, lung cancer has remained one of the chief contributors to global mortality rates. Despite a long history and recent progress in diagnostic assays, lung cancer (LC) remains a blight on sustainable human development, with cigarette smoking being the most evident cause. The majority of LC deaths are due to non-small cell lung cancer, of which lung adenocarcinoma and squamous cell carcinoma (SCC) are subtypes. Much is known about the implicit LC biomarkers; as a result, there is an urgent need to develop and apply accurate screening procedures and probes for prompt and accurate initial detection. Methods such as computed tomography (CT), magnetic resonance imaging (MRI), positron emission tomography (PET), and chest radiography (CR) are generally applied to screen lung nodule abnormalities via image formation. Conventional imaging assays are restricted to size, margin, and density identification, which hinders conclusive inference and determination of the root cause. The research landscape is swiftly shifting toward combined probe development via the simultaneous application of computer-aided diagnosis (CAD) systems, rebiopsy, electron microscopy, phase-contrast microscopy, and fluorescence spectroscopy. The last five years have witnessed significant development pertaining to stage-dependent molecular and functional imaging and more recent radiogenomics for detecting genomic and proteomic dynamics in lung nodules. Artifacts at the nanoscale, such as those found in nanomaterials (NMs), are having an impact, as quantum confinement effects in these materials modulate their optical attributes, leading to faster and more resilient capture abilities. With such insights, this chapter pinpoints topical advancements in imaging methods for LC diagnosis that will allow radiologists to classify lung nodules more accurately.