• To set out the different tumour subtypes encompassed within the spectrum of “lung adenocarcinoma” (pre-malignant and malignant). • To define their main histological and radiological features. • To describe the diagnostic work-up. • To briefly describe the importance of new molecular pathways.

In 2012 lung cancer was responsible for 1,6million deaths worldwide. It represents a leading cause of disease as the most common cancer in men and third most common cancer in women [1], (fig. 1). Traditionally it has been classified depending on their appearance in optical microscopy. Four main histological types can be distinguished (fig. 2): Adenocarcinoma (40%) Squamous cell carcinoma (25-30%) Large cell carcinoma (15%) Small cell carcinoma (~15%) In 2011 a new lung adenocarcinoma classification was released by a multidisciplinary joint commission of the...

Normal histology: The mucosa of bronchi and proximal bronchioles is lined by a ciliated, columnar epithelium interspersed with goblet (mucus-producing cells), basal and neuroendocrine cells. Alveolar walls consist of tightly connected pneumocytes type I and sparse pneumocytes type II responsible for the production of surfactant [9]. Clara cells tend to replace mucous cells in distant bronchioles and are also important in physiology and physiopathology of the lung (fig. 4). The term adenocarcinoma encompasses all tumours with glandular differentiation. Molecular studies have proved two different histogenetic...

Lung adenocarcinoma comprises a heterogeneous group of tumours with different histological and radiological manifestations. Molecular features have proven to be paramount in diagnosis and treatment. Whereas current management of lung nodules and masses is based on size, “texture” (solid, subsolid) and histological sampling, in the future computer reliant assessment likely will play a central role in non-invasive tumour characterization and response evaluation. Likewise, targeted treatments have repercussions on image studies the radiologist must be aware of in order to appropriately evaluate the imaging studies ofpatients...

1. Global Cancer Observatory. http://gco.iarc.fr/. Accessed July 2, 2017. 2. Travis WD, Brambilla E, Noguchi M, et al. International Association for the Study of Lung Cancer/American Thoracic Society/European Respiratory Society International Multidisciplinary Classification of Lung Adenocarcinoma. J Thorac Oncol Off Publ Int Assoc Study Lung Cancer. 2011;6(2):244–285. 3. Godoy MCB, Naidich DP. Subsolid Pulmonary Nodules and the Spectrum of Peripheral Adenocarcinomas of the Lung: Recommended Interim Guidelines for Assessment and Management. Radiology. 2009;253(3):606–622. 4. Austin JH, Garg K, Aberle D, et al. Radiologic implications of...