BACKGROUND: It is difficult to predict the malignant potential of pancreatic neuroendocrine tumors (PNETs) precisely. This study investigated the validity of a new grading system adopted by the World Health Organization 2010 classification to determine risk factors for recurrence of PNETs. METHODS: Data of 70 patients with PNETs who underwent curative resection were retrospectively examined by uni- and multivariate analyses. Histopathological findings were re-reviewed by experienced pathologists. NET G1 was defined as mitotic count <2 per 10 high power fields (HPF) and/or ≤2% Ki67 index, and NET G2 as 2-20 mitosis per 10 HPF and/or 3-20% Ki67 index. RESULTS: There were 58 patients with NET G1 and 12 with NET G2. Incidence of recurrence was 11.4%. Univariate analysis demonstrated significant risk factors for recurrence including NET G2 of histological grade (P = 0.0089), male gender (P = 0.0333), tumor size ≥ 20 mm (P = 0.0117), lymph node metastasis (P = 0.0004), liver metastasis (P < 0.0001), lymphatic invasion (P = 0.046), and neural invasion (P = 0.0002). By multivariate analysis, histological grade (hazard ratio; 59.76, P = 0.0022) and neural invasion (hazard ratio; 147.49, P = 0.0016) were significantly associated with recurrence of PNETs. CONCLUSIONS: This study confirmed the prognostic relevance of the new grading classification and that evaluation of perineural invasion and histological grade should be considered as prognostic predictors in well-differentiated PNETs (NET G1 and G2).
BACKGROUND: It is difficult to predict the malignant potential of pancreatic neuroendocrine tumors (PNETs) precisely. This study investigated the validity of a new grading system adopted by the World Health Organization 2010 classification to determine risk factors for recurrence of PNETs. METHODS: Data of 70 patients with PNETs who underwent curative resection were retrospectively examined by uni- and multivariate analyses. Histopathological findings were re-reviewed by experienced pathologists. NET G1 was defined as mitotic count <2 per 10 high power fields (HPF) and/or ≤2% Ki67 index, and NET G2 as 2-20 mitosis per 10 HPF and/or 3-20% Ki67 index. RESULTS: There were 58 patients with NET G1 and 12 with NET G2. Incidence of recurrence was 11.4%. Univariate analysis demonstrated significant risk factors for recurrence including NET G2 of histological grade (P = 0.0089), male gender (P = 0.0333), tumor size ≥ 20 mm (P = 0.0117), lymph node metastasis (P = 0.0004), liver metastasis (P < 0.0001), lymphatic invasion (P = 0.046), and neural invasion (P = 0.0002). By multivariate analysis, histological grade (hazard ratio; 59.76, P = 0.0022) and neural invasion (hazard ratio; 147.49, P = 0.0016) were significantly associated with recurrence of PNETs. CONCLUSIONS: This study confirmed the prognostic relevance of the new grading classification and that evaluation of perineural invasion and histological grade should be considered as prognostic predictors in well-differentiated PNETs (NET G1 and G2).
Authors: Cornelius A Thiels; John R Bergquist; Danuel V Laan; Kristopher P Croome; Rory L Smoot; David M Nagorney; Geoffrey B Thompson; Michael L Kendrick; Michael B Farnell; Mark J Truty Journal: J Gastrointest Surg Date: 2016-02-29 Impact factor: 3.452
Authors: Masayuki Tanaka; Max Heckler; André L Mihaljevic; Pascal Probst; Ulla Klaiber; Ulrike Heger; Simon Schimmack; Markus W Büchler; Thilo Hackert Journal: Ann Surg Oncol Date: 2020-07-27 Impact factor: 5.344
Authors: Alexander V Fisher; Alexandra G Lopez-Aguiar; Victoria R Rendell; Courtney Pokrzywa; Flavio G Rocha; Zaheer S Kanji; George A Poultsides; Eleftherios A Makris; Mary E Dillhoff; Eliza W Beal; Ryan C Fields; Roheena Z Panni; Kamran Idrees; Paula Marincola Smith; Clifford S Cho; Megan V Beems; Shishir K Maithel; Emily R Winslow; Daniel E Abbott; Sharon M Weber Journal: J Gastrointest Surg Date: 2019-01-18 Impact factor: 3.452