Malignant potential of small pancreatic neuroendocrine neoplasm and its risk factors: A multicenter nationwide study.

BACKGROUND: Pancreatic neuroendocrine neoplasms (PNENs) show heterogeneous biological behavior, and most small PNENs show indolent features. Consequently, selected cases can be considered for observation only, according to the National Comprehensive Cancer Network guideline, however, supporting clinical evidence is lacking. We investigated the clinical course of small PNENs and their risk factors for malignant potential. METHODS: A total of 158 patients with small pathologically confirmed PNENs ≤2 cm in initial imaging were retrospectively enrolled from 14 institutions. The primary outcome was any metastasis or recurrence event during follow-up. RESULTS: The median age was 57 years (range, 22-82 years), and 86 patients (54%) were female. The median tumor size at initial diagnosis was 13 mm (range, 7-20 mm). PNENs were pathologically confirmed by surgery in 137 patients and by EUS-guided fine needle aspiration biopsy (EUS-FNAB) in 21 patients. Eight patients underwent EUS-FNAB followed by surgical resection. The results of WHO grade were available in 150 patients, and revealed 123 grade 1, 25 grade 2, and 2 neuroendocrine carcinomas. A total of 145 patients (92%) underwent surgical resection, and three patients had regional lymph node metastasis. During the entire follow-up of median 45.6 months, 11 metastases or recurrences (7%) occurred. WHO grade 2 (HR 13.97, 95% CI 2.60-75.03, p = 0.002) was the only predictive factor for malignant potential in multivariable analysis. CONCLUSIONS: WHO grade is responsible for the malignant potential of small PNENs ≤2 cm. Thus, EUS-FNAB could be recommended in order to provide early treatment strategies of small PNENs.

NSAID is inversely associated with asymptomatic gastric ulcer: local health examination data from the Korean National Health Insurance Corporation.

BACKGROUND. Silent peptic ulcer has been considered to be associated with nonsteroidal anti-inflammatory drug (NSAID). The recent studies have reported no relationship between them. AIM. We attempted to investigate an association between asymptomatic peptic ulcer and NSAID in Korean adults. METHODS. The subjects were enrolled from participants visiting Myongji Hospital for health examination program of the Korean National Health Insurance Corporation. The questionnaires were designed to investigate individual medical information and gastroduodenal symptoms. RESULTS. From May 2005 to March 2009, 5459 participants were enrolled and 299 participants were excluded. Of 5160 participants, 3144 (60.9%) participants were asymptomatic and 424 (8.2%) participants had peptic ulcer. Among 3144 asymptomatic participants, NSAID-taking participants had the odds ratio of 1.4 [95% confidence interval (CI): 0.7-2.6, p = 0.339] for the risk of peptic ulcer. Among 424 peptic ulcer patients, 247 (58.3%) were asymptomatic. They had lower prevalence of NSAID use (4.9% vs. 14.7%). The asymptomatic gastric ulcer patients had smaller size and more frequent healing stage than the symptomatic gastric ulcer patients. In multivariable analysis of 424 peptic ulcer patients, NSAID patients had the odds ratio of 0.249 (95%CI: 0.115-0.536, p < 0.05) for asymptomatic peptic ulcer. In subgroup analysis of 284 gastric ulcer patients, NSAID-taking patients had the odds ratio of 0.263 (95% CI: 0.105-0.657, p = 0.004) for asymptomatic peptic ulcer. CONCLUSION. NSAID has an inverse association with asymptomatic patients with gastric peptic ulcer, but has no association with gastroduodenal symptoms in duodenal ulcer patients. These suggest that NSAID may be associated with gastroduodenal symptoms rather than masking symptoms, at least in gastric ulcer patients.