The International Association for the Study of Lung Cancer (IASCL) grading system can precisely predict patient outcomes for patients with lung cancer, according to a study published in Lung Cancer. In a retrospective study of 648 patients with resected lung adenocarcinomas, researchers assessed the clinical implications of the IASCL beyond the discrimination of patient prognosis while examining biological differences among highgrade subtypes. They evaluated immunophenotypic and clinicopathologic genotypic features as well as treatment outcomes. Additionally, they individually evaluated differences among grades and the clinical effect of different high-grade components: solid (SOL) patterns and micropapillary (MIP). The study team observed well-stratified survival outcomes according to the grading system. In multivariable analysis, grade 3 tumors revealed aggressive clinicopathologic features while acting as an independent prognostic factor. While the proportion of the SOL component did not impact prognosis, the study confirmed the prognostic difference bordering on the 20% cutoff of the MIP proportion. In grade 3 tumors, a survival benefit from adjuvant chemotherapy was noted regardless of histologic subtype, but not in grade 1 to 2 tumors.
