Pancreatic neuroendocrine tumors (PNETs): incidence, prognosis and recent trend toward improved survival.
BACKGROUND
Pancreatic neuroendocrine tumors (PNETs) are uncommon neoplasms that can present with symptoms of hormone overproduction. We evaluated the incidence, prognosis, and temporal trends of PNETs.


METHODS
We analyzed all cases of PNETs registered in the Surveillance, Epidemiology, and End Results database from 1973 to 2000. Age-adjusted incidence and survival rates were calculated and survival trends over time were evaluated.


RESULTS
We identified 1483 cases of PNETs. The crude annual incidence per 1,000,000 was 1.8 in females and 2.6 in males and increased with advancing age. The incidence increased over the study period. Most patients (90.8%) had nonfunctional tumors. Advanced stage, higher grade, and age were the strongest predictors of worse survival. Patients with functional tumors had better outcomes than patients with nonfunctional tumors in both univariate and multivariate analysis (P = 0.004). Survival time increased over the period from 1973 to 2000. No differences were seen in the distribution of stage or age at diagnosis among time periods.


CONCLUSIONS
PNETs are uncommon neoplasms but the incidence may be increasing. Age, grade, stage, and functional status predict survival in patients with PNETs. Survival has improved over time, but this is not explained by earlier diagnosis or stage migration.
Division of Medical Oncology, Mayo Clinic College of Medicine, Rochester, MN, USA. thorvardur-halfdanarson@uiowa.edu
T R
TR
Halfdanarson
K G
KG
Rabe
J
J
Rubin
G M
GM
Petersen
D000328:Adult; D000367:Age Factors; D000368:Aged; D000369:Aged, 80 and over; D005260:Female; D006801:Humans; D015994:Incidence; D008297:Male; D008875:Middle Aged; D009367:Neoplasm Staging; D018358:Neuroendocrine Tumors / Q000453:epidemiology* / Q000473:pathology; D010190:Pancreatic Neoplasms / Q000453:epidemiology* / Q000473:pathology; D011379:Prognosis; D018426:SEER Program; D012737:Sex Factors; D015996:Survival Rate / Q000639:trends; D014481:United States / Q000453:epidemiology