Preliminary results of a Japanese nationwide survey of neuroendocrine gastrointestinal tumors.
BACKGROUND
We conducted a nationwide survey to estimate the incidence of neuroendocrine gastrointestinal tumors (NETs) newly diagnosed in Japan from 2002 through 2004.


METHODS
Data on 1541 patients, 514 pancreatic endocrine tumors (PETs) and 1027 gastrointestinal carcinoids (GICs), were collected and analyzed.


RESULTS
Nonfunctioning tumors (NF-PET) constituted 47.7% of PETs. Next in frequency were insulinoma (31.7%) and gastrinoma (8.6%). Malignancy was frequent in NF-PETs (46.1%) and gastrinomas (45.5%), but only 7.4% of insulinomas were malignant. The incidence of multiple endocrine neoplasia type-1 associated with PETs was 7.4%. The incidence of GICs was 28.8%, 5.2%, and 66.0% in foregut, midgut, and hindgut, respectively. Carcinoid syndrome and metastases were observed in only 1.7% and 5.6% of GICs, respectively.


CONCLUSIONS
The incidence of NETs in Japan was clarified by this preliminary study. Comparatively large differences in GICs between Japan and Western nations were present with regard to the location, symptomatic status, and prevalence of malignancy.
Ito
Tetsuhide
T
Department of Medicine and Bioregulatory Science, Graduate School of Medical Sciences, Kyushu University, 3-1-1 Maidashi, Fukuoka, Japan.
Tanaka
Masao
M
Sasano
Hironobu
H
Osamura
Yoshiyuki R
YR
Sasaki
Iwao
I
Kimura
Wataru
W
Takano
Koji
K
Obara
Takao
T
Ishibashi
Miyuki
M
Nakao
Kazuwa
K
Doi
Ryuichiro
R
Shimatsu
Akira
A
Nishida
Toshirou
T
Komoto
Izumi
I
Hirata
Yukio
Y
Imamura
Masayuki
M
Kawabe
Ken
K
Nakamura
Kazuhiko
K
D005770:Gastrointestinal Neoplasms / Q000453:epidemiology*; D006801:Humans; D015994:Incidence; D007564:Japan; D018358:Neuroendocrine Tumors / Q000453:epidemiology*