UNASSIGNED: @entity5 (NETs) are rare neoplasms with heterogeneous clinical behavior and potential long-term survival. In 2006/2007, the European @entity5 Society introduced an important parameter, grade (based on mitoses and Ki-67 proliferation rate), which became part of the latest 2010-WHO classification. Since this is an important tool in the choice of therapeutic algorithm of @entity1 with NETs, our aim was to audit whether retrospective reclassification is possible and feasible and correlate pathological findings with survival. From the histopathology archive, 338 GEP-NETs (1994-2014) were identified, of which 250 were diagnosed pre-2010 and 80 of these have needed, up till now, classification (morphology and grade-mitotic count/Ki-67). Morphology was @entity3271 ( @entity3271 ) in 74 cases while only 6 cases were @entity1073 ( @entity1073 ). Grade was reclassified: G1-45 cases (56  %); G2-28 cases (35  %); G3-7 cases (9  %). Overall survival (OS) in @entity3271 NETs was strikingly better compared to @entity5 . Differences in OS between grade were statistically significant (p  <  0.0001) and, in particular, grade identified a subgroup of @entity1 with @entity3271 lesions but with less favorable clinical behavior (OS at 5  years: G1-89  %; G2-48  %; G3-0  %; G1 vs G2 p  =  0.03). Feasibility analysis quantified time for reclassification to be between 45 and 64  min/case. Our series confirms the importance of grade in prognostic stratification and underlines that reclassification is feasible, and may prove worthwhile in @entity1 management, especially in view of the potential long survival of @entity1 with NETs and risk of use of inappropriate therapies.

Twenty years of XXXX : is reclassification worthwhile and feasible?

@entity5 :: ('MESH:D009369', 'Disease') :: ['Gastroenteropancreatic (GEP) neuroendocrine tumors', 'PD neoplasms', 'Neuroendocrine Tumors'] @entity1 :: ('9606', 'Species') :: ['patients', 'patient'] @entity1073 :: ('MESH:D020522', 'Disease') :: ['PD', 'poorly differentiated'] @entity3271 :: ('MESH:D009837', 'Disease') :: ['well differentiated', 'WD']
@entity5 :: (MESH:D009369,Disease) :: ['gastroenteropancreatic neuroendocrine tumors']
