Classification histologique des cancers broncho-pulmonaires non à petites cellules

Non small cell lung carcinoma comprise, according to the 2004 WHO classification, the squamous cell carcinoma, the adenocarcinoma and the large cell carcinoma, along with their preneoplastic conditions. A new classification of pulmonary adenocarcinoma has been recently proposed by the ATS/ERS/IASCLC meetings, providing new histopronostic entities such as in situ adenocarcinoma, replacing the bronchioloalveolar carcinoma which term has been suppressed, and the minimally invasive adenocarcinoma, characterized by an invasion equal or of less than 5 mm or representing less than 10% of the tumor. These forms of adenocarcinoma harbor a very favourable prognosis after resection, with 100% of survival at 5 years. The term adenocarcinoma of mixed type has been changed for that of invasive adenocarcinoma, and the distinction of the predominant architectural component, associated with a prognosis and a molecular profile, is recommended. This classification also provides new recommendations regarding the terminology to use for small specimens and propose an algorithm of immunostainings to better characterize non-small cell lung carcinoma.