言語種別	英語
発表タイトル	Risk of pancreatic cancer in chronic pancreatitis and clinicopathological characteristics of chronic pancreatitis-associated pancreatic cancer
会議名	JDDW 2026 KOBE 第34回日本消化器関連学会週間
学会区分	全国規模の学会
発表形式	口頭
講演区分	シンポジウム・ワークショップ パネル（公募）
発表者・共同発表者	◎丸尾基展，　池浦司，　長沼誠
発表年月日	2026/11/06
開催地 （都市, 国名）	神戸コンベンションセンター
概要	[Background] Chronic pancreatitis is a risk factor for pancreatic cancer, but its actual cancer risk and the characteristics of pancreatic cancer arising in chronic pancreatitis remain unclear. [Aim] To evaluate pancreatic cancer risk in chronic pancreatitis using the standardized incidence ratio (SIR) and compare the clinicopathological characteristics of chronic pancreatitis-associated pancreatic cancer with those of sporadic pancreatic cancer. [Methods] Patients diagnosed with chronic pancreatitis between 2006 and 2024 were included. SIR was calculated from the observed and age- and sex-adjusted expected numbers of pancreatic cancer. Among patients who developed pancreatic cancer, 4 who underwent pancreatectomy were assigned to the chronic pancreatitis-associated pancreatic cancer group. Fifty-four patients with sporadic pancreatic cancer who underwent upfront surgery served as controls. Clinical features, survival outcomes, and immunohistochemical expression of p53, p16, and SMAD4 were compared. [Results] Among 133 patients with chronic pancreatitis, 7 developed pancreatic cancer over 6.8 years of median follow-up. The SIR was 13.7 (95% CI, 5.5-28.1). No significant differences were observed in clinical features or survival outcomes. Abnormal p53 expression was significantly less frequent in the chronic pancreatitis-associated pancreatic cancer group than in controls (1/4 vs. 46/54, p=0.003), whereas p16 and SMAD4 did not differ. [Conclusion] Chronic pancreatitis is a high-risk condition for pancreatic cancer and may require long-term surveillance. Pancreatic cancer arising in chronic pancreatitis may have distinct molecular pathological features.