Rault-Petit B, et al. - In this largest study using the latest pathological criteria for completion right hemicolectomy (RHC) in appendix neuroendocrine tumor (A-NET), researchers sought to determine the predictive factors of lymph node involvement (LN+) in patients with A-NET. Among 403 patients, A-NETs were: within tip (67%), body (24%) or base (9%) of the appendix; tumor size was < 1 cm (62%), 1 to 2 cm (30%), or >2 cm (8%); grade 1 (91%); mesoappendix involvement 3 mm (5%); lymphovascular (15%) or perineural (24%) invasion; and positive resection margin (8%). According to the European NeuroEndocrine Tumor Society (ENETS) recommendations, RHC was recommended in 85 patients (21%). The ENETS guidelines agreed to the multidisciplinary tumor board for complementary RHC in 89%. Lymph node (LN) resection was done in 100 (25%) patients undergoing RHC; 26 of these had LN+. They noted tumor size (best cut-off at 1.95 cm), lymphovascular and perineural invasion, and pT classifications to be correlated with LN+. LN+ was noted in 8 (18%) patients among the 44 patients who underwent RHC for a tumor of 1 to 2 cm in size. This subgroup of patients was identified to have no predictive factor of LN+ (base, resection margins, grade, mesoappendix, lymphovascular, perineural involvement).