title: Behavior of Small, Asymptomatic, Nonfunctioning Pancreatic Neuroendocrine Tumors (NF-PNETs).
abstract: Small nonfunctioning pancreatic neuroendocrine tumors (NF-PNETs) usually exhibit minimal or no growth over many years. However, there is a controversy regarding the optimal management of incidentally discovered, small NF-PNETs. This study aimed to gain insights into tumor behavior and potential strategies for clinical management.We retrospectively reviewed a total of 202 patients with a suspected PNET (size 2 cm or smaller) at Samsung Medical Center from January 1, 1995 to April 30, 2012. Among these patients, 72 patients were excluded and 145 patients were enrolled in our study. Patients were included if the size of the tumor was ≤2 cm without familial syndrome, radiographic evidence of local invasion or metastases.Among the 145 patients, 76 patients (52.4%) had pathologically confirmed PNETs. Eleven (14.5%) and 3 (3.9%) of these 76 patients were diagnosed with NET G2 and G3, respectively. PNETs measuring 1.5 cm or more in size had a higher probability of being classified as NET G2 or G3 compared with PNETs measuring <1.5 cm (P = 0.03). Older age (≥55 years) and a meaningful tumor growth (≥20% or ≥5 mm) were significantly associated with NET G2 or G3 (P < 0.05).Older age (≥55 years), larger tumor size (≥1.5 cm), and a meaningful tumor growth (≥20% or ≥5 mm) were associated with NET G2 or G3. Intensive follow-up could be an acceptable approach in small (especially <1.5 cm), asymptomatic, NF-PNETs.
authors.affiliation: From Department of Medicine, Incheon Sarang Hospital, Incheon, Korea (JGJ); Department of Medicine, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Korea (KTL, YSW, JKL, KHL, JCR); Department of Pathology, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Korea (K-TJ).
authors.forename: Jae Gu
authors.initials: JG
authors.lastname: Jung
authors.forename: Kyu Taek
authors.initials: KT
authors.lastname: Lee
authors.forename: Young Sik
authors.initials: YS
authors.lastname: Woo
authors.forename: Jong Kyun
authors.initials: JK
authors.lastname: Lee
authors.forename: Kwang Hyuck
authors.initials: KH
authors.lastname: Lee
authors.forename: Kee-Taek
authors.initials: KT
authors.lastname: Jang
authors.forename: Jong Chul
authors.initials: JC
authors.lastname: Rhee
mesh_terms: D000328:Adult; D000368:Aged; D005260:Female; D006801:Humans; D033162:Incidental Findings; D008297:Male; D008875:Middle Aged; D018358:Neuroendocrine Tumors / Q000453:epidemiology* / Q000473:pathology; D010179:Pancreas / Q000473:pathology; D010190:Pancreatic Neoplasms / Q000453:epidemiology* / Q000473:pathology; D056910:Republic of Korea / Q000453:epidemiology; D012189:Retrospective Studies; D057832:Watchful Waiting