Early Lung Cancer With Lepidic Pattern

Adenocarcinoma in Situ, Minimally Invasive Adenocarcinoma, and Lepidic Predominant Adenocarcinoma

Wilko Weichert; Arne Warth


Curr Opin Pulm Med. 2014;20(4):309-316. 

In This Article

Diagnostic Reproducibility of the Lepidic Growth

With a mean correlation coefficient of 0.78, lepidic growth is associated with a good interobserver agreement.[17] However, the delineation from papillary or acinar growth has been found challenging, but training sessions improve the interobserver agreement.[16] Furthermore, cases with obscuring inflammation as well as lepidic involvement of emphysematous areas can be difficult with respect to correct pattern interpretation. This underlines the need for international efforts in this regard, which was further emphasized by an interobserver study on the reproducibility of histopathological subtypes and invasion demonstrating that more precise definitions and better education on the interpretation of existing terminology are required to improve proper diagnosis of purely in-situ disease.[15] Furthermore, Thunnissen et al.[44] analyzed three-dimensional reconstructions of pulmonary ADCs from serial sections for the influence of surgical atelectasis on the diagnosis of a 'lepidic' pattern. It was shown that for reliable ADC subtyping, pathologists must be aware of artifacts because of compressed or collapsed tissue to avoid misclassification of the lepidic pattern as papillary growth.