內視鏡超音波併細針抽吸在處理胰臟囊狀腫瘤的臨床角色

Abstract

研究背景： 隨著影像技術的改善和橫斷式影像掃描的頻繁使用，如超音波，電腦斷層掃描和磁振造影，臨床上，胰臟囊狀腫瘤被意外發現地越來越多。據之前的研究統計，胰臟囊狀腫瘤的盛行率介於3％至24.3％之間。這些胰臟囊狀腫瘤依其性質基本上可以分為非致癌性和致癌性。而致癌性的胰臟囊狀腫瘤具有不同的惡性病變潛力，從小於1%到60％以上皆有。目前胰臟囊性腫瘤的標準治療是手術治療。然而此類手術的併發症和死亡率是相當地高。 因此，如何做出正確的診斷讓患者得到合適的處置，如手術切除或定期追蹤，是一個重要的議題。現今，有兩個國際共識指引，國際胰臟學會(IAP, 2012)和美國胃腸醫學會(AGA, 2015)，針對胰臟囊狀腫瘤提供處理流程建議。處理流程中提到非侵入性方法（如橫斷式影像掃描）和侵入性方法（內視鏡超音波併細針抽吸）的使用時機。然而，這些處理流程的建議接建立於已知病理結果的回溯性研究，其證據力相對薄弱。我們此次的研究是在評估內視鏡超音波併細針抽吸在現行指引中是否具有臨床影響力足以改變診斷及治療。 材料和方法： 本研究回顧性分析台灣國立大學附設醫院的病患，於西元2009年八月至西元2015年十二月間曾接受非侵入性影像學檢查及內視鏡超音波併細針抽吸。所有病患的臨床資訊皆由醫院電子醫療記錄中取得。而所有病患接受過的橫斷式影像掃描檢查皆由一名本院放射科醫師重新判讀以獲取影像診斷結果。經由電腦斷層或磁振造影檢查得到的結果定義為內視鏡超音波併細針抽吸術前診斷，而內視鏡超音波併細針抽吸術後診斷則是依據病理報告(接受手術者)或內視鏡超音波併細針抽吸的結果(綜合細胞學和組織液分析)。 結果與討論： 此次研究分析了119名患者，總共有130例的胰臟囊狀腫瘤。63%的病例接受過電腦斷層掃描檢查，88%的病例接受過磁振造影檢查，而全部病例皆接受內視鏡超音波併細針抽吸檢查。我們比較內視鏡超音波併細針抽吸術前診斷和內視鏡超音波併細針抽吸術後診斷，發現兩者間的一致性分別為37％(經由電腦斷層診斷)和43％(經由磁振造影診斷)。進一步分析顯示，不論接受何種影像檢查，男性患者在內視鏡超音波併細針抽吸術前診斷和內視鏡超音波併細針抽吸術後診斷具有統計上顯著的一致性（p <0.05）。此外，在接受磁振造影診斷的病患中，若有下列因子者--高BMI值、無酒精飲用史及胰管擴張（>5mm），接受內視鏡超音波併細針抽吸會得到和臨床診斷差異顯著的結果。 結論： 內視鏡超音波併細針抽吸能提供比其他橫斷式影像檢查更多的信息，並影響胰臟囊狀腫瘤的診斷。本研究建議有胰臟囊狀腫瘤的患者若具備女性身分、BMI值偏高、無飲用酒精病史，在安排磁振造影檢查後若有胰管擴張現象，應進一步接受內視鏡超音波併細針抽吸作為後續診斷及治療的依據。

Background: As the advance in the image modalities and frequent usage of cross-sectional images, like ultrasound, computed tomography (CT) and magnetic resonance imaging (MRI), there are more and more incidental detection of pancreatic cystic tumors (PCTs) in clinical practice, usually for unrelated reasons. The prevalence of PCTs ranged from 3 to 24.3%. According to the previous studies, these PCTs could be categorized into non-neoplastic and neoplastic lesions. Subclassifications of neoplastic PCTs have the different potential to become malignant, from almost 0% to over 60%. Currently, the standard treatment of PCTs is surgery. However, the morbidity and mortality of surgery are relatively high. Thus, how to make a right decision to provide patients the adequate management, either follow-up or surgery, is an important issue. Nowadays, there are two international consensus guidelines, 2012 International Association of Pancreatology (IAP) and the 2015 American Gastroenterological Association (AGA) guidelines, for management of PCTs. Non-invasive methods (such as cross-sectional images) and invasive methods (endoscopic ultrasound with fine needle aspiration, EUS-FNA) are offered in the algorithm. However, these guidelines are based on the retrospective studies with pathology-proven results. The level of evidence is low. Our study is going to evaluate the clinical impact of EUS-FNA that could change the diagnosis and decision makig in current guidelines. Methods and materials: We retrospectively reviewed the patients in national Taiwan university hospital who had received both non-invasive image studies and EUS-FNA from Aug. 2009 to Dec. 2015. The baseline demographic data were collected from the electrical medical record. Images of CT and MRI were reviewed by one radiologist. Pre-EUS diagnosis was defined according to the results of CT or MRI. Post-EUS diagnosis was defined according to the pathology (with surgery) or results from EUS-FNA (combined cytology and fluid analysis). Results: One hundred and nineteen patients with 130 PCTs were analyzed. 63% of the PCTs were evaluated by CT scan, 88% of the PCTs were evaluated by MRI, and all the PCTs were evaluated by EUS-FNA. The pre-EUS diagnosis made by CT or MRI has 37% or 43% consistency to post-EUS diagnosis, respectively. Further analysis revealed that only male has clinical significancy (p<0.05) in both CT and MRI group for consistency between pre-EUS diagnosis and post-EUS diagnosis. Moreover, BMI level, history of alcohol consumption, and dilated P-duct (>5mm) in image are other significant variables (p<0.05) in MRI group for diagnositic consistency. Conclusions: EUS-FNA provides more information than other cross-sectional images and has impacts on the diagnosis of PCTs. Patiens with female gender, higher BMI level, no history of alcohol usage and dilated P-duct in MRI study would be recommended to receive EUS-FNA for further differential diagnosis and treatment plan.