Grade 3 Lung Carcinoids/NETs: The IASLC Pathology Committee Study with Proposal of a New Diagnostic Category.
INTRODUCTION Lung carcinoids are well-differentiated neuroendocrine tumors (NETs), designated in the current thoracic WHO classification as typical carcinoids (grade 1) and atypical carcinoids (grade 2), whereas rare tumors with carcinoid/NET morphology and >10 mitoses/2mm2 are designated as large cell neuroendocrine c...