췌장의 비기능성 내분비 종양의 임상병리학적 특성 및 예후인자

Purpose: Nonfunctioning endocrine tumors of the pancreas have no specific symptoms. Therefore, diagnosis is usually delayed and the malignancy rate at the time of diagnosis is reported to be higher than 50%. However, it is difficult to discriminate malignant from benign nonfunctioning endocrine tumors preoperatively. The purpose of this study was to investigate clinical characteristics of nonfunctioning endocrine tumors of the pancreas, including predictive factors of malignancy and prognostic factors affecting long-term survival. Methods: Between 1992 and 2010, clinicopathological data of 53 patients with nonfunctioning endocrine tumors proven by surgical pathology were reviewed retrospectively. Results: Of the 53 patients, mean age was 54 years-old and the male to female ratio was 1 : 1.2 Median follow up was 32.1 months. At the time of diagnosis, liver metastasis was detected in 4 patients. Curative resection was achieved in 49 patients, and 17% of them had recurrence, which was most common in liver. The overall 5-year survival rate was 85.1%. Both the WHO classification (p＜0.001) and AJCC staging (p＜0.001) correlated well with long-term survival. Univariate analysis revealed preoperative body weight loss (p＜0.001), weak enhancement at the early arterial phase (p=0.043), lymph node metastasis (p＜0.001), liver metastasis (p=0.001), perineural invasion (p=0.001), or lymphovascular invasion (p=0.010) as prognostic factors. Conclusion: Nonfunctioning endocrine tumor of the pancreas has favorable survival outcomes. Lymph node metastasis (p＜0.001), liver metastasis (p=0.001), perineural invasion (p=0.001), and lymphovascular invasion (p=0.010) are poor prognostic factors.