Received: 4 May 2017 Accepted: 21 June 2017 Published on: 30 August 2017
Prognoses in patients with primary gastrointestinal
neuroendocrine neoplasms based on the proposed new
Department of Gastrointestinal Surgery, West
China Hospital, Sichuan University, Chengdu,
Department of Pathology, West China Hospital,
Sichuan University, Chengdu, Sichuan, China
Intensive Care Unit, West China Hospital,
Sichuan University, Chengdu, China
Bo Zhang, Department of Gastrointestinal
Surgery, West China Hospital, Sichuan Univer-
sity, Chengdu 610041, Sichuan, China.
Aim: The aim of this study is to investigate the clinicopathological characteristics, as well as
explore the prognostic accuracy of the proposed new classiﬁcation in gastrointestinal NENs (GI-
Methods: Patients diagnosed with GI-NENs were retrospectively indentiﬁed from existing
databases of the pathological institute at our institution from January 2009 to November 2015.
Results: We identiﬁed 414 patients with GI-NENs, 250 cases were diagnosed as neuroendocrine
tumor G1 (NET G1), 25 as neuroendocrine tumor G2 (NET G2), 53 as neuroendocrine tumor
G3 (NET G3), 55 as neuroendocrine carcinoma G3 (NEC G3), and 31 as mixed adenoneuroen-
docrine carcinoma (MANEC); the overall survival (OS) rate at three years were 94.9%, 91.7%,
74.3%, 62.7% and 38.1%, respectively. The difference in progression-free survival (PFS) duration
among the patients with NET G1, NET G2, NET G3, NEC G3, and MANEC was statistically signif-
icant (P < 0.001). However, the PFS of NEC G3 and MANEC was low and similar (P = 0.090). In
multivariate analysis of patients with GI-NENs, surgical margin, comorbidity, proposed new clas-
siﬁcation and tumor location were useful predictors of OS (P < 0.05).
Conclusion: Our ﬁndings suggest that the proposed new classiﬁcation can accurately reﬂect the
clinical outcome, together with surgical margin, comorbidity, and tumor location may be meaning-
ful prognostic factors for the OS of GI-NENs.
classiﬁcation, gastrointestinal, neuroendocrine neoplasms
Neuroendocrine neoplasms (NENs) are epithelial tumors with a pre-
dominant neuroendocrine differentiation, which originate in a great
diversity of tissues.
The results from the National Cancer Registry
for Gastroenteropancreatic Neuroendocrine Tumors (RGETNE) have
shown that approximately half of all NENs are GI-NENs, with high-
est frequency being observed in the small intestine, appendix and
stomach, which signiﬁcantly differ with that observed in Surveillance,
Epidemiology and End Results (SEER) Program tumor registry.
incidence of NENs varies between 3.24 and 6.50/100 000,
for higher incidence in men compared with women.
In addition, GI-
NENs accounted for an increasing proportion of NENs. According to
the SEER database, the incidence rate of GI-NENs was 5.25/100 000
in 2004, with a ﬁve-fold increase from that 30 years earlier.
increase was likely caused in part by improvements in classiﬁcation of
these tumors. Nowadays, surgical resection undoubtedly remains the
mainstay of the potentially curative treatment for the GI-NENs. How-
ever, NENs may be asymptomatic and clinically silent when diagnosed
but some will display malignant characteristics even underwent surgi-
cal resection; they often have unpredictable biological behavior.
Currently, there is no accepted uniformed grading system for
NENs. The ability to stratify patients with NENs into prognostic
groups could yield beneﬁts to the patients. Nevertheless, the prognos-
tic classiﬁcation of NENs has been challenging due to their rarity. In
2000, the WHO classiﬁcation divided digestive system NENs into ﬁve
Asia-Pac J Clin Oncol. 2018;14:e37–e44.
2017 John Wiley & Sons Australia, Ltd e37wileyonlinelibrary.com/journal/ajco