局灶性胰腺炎誤診為胰尾癌一例

李紹軍 王京芬 孫孚波

患者男，54歲。因“上腹部疼痛半年余”入院。患者半年前無明顯誘因出現上腹部持續性隱痛，不放射，發作無時間規律。在當地以“慢性胃炎”治療未見好轉，后行CT檢查，顯示胰尾低密度影，遂入我院。患者既往無吸煙及飲酒史。體檢：皮膚鞏膜無黃染，鎖骨上淋巴結未腫大，腹軟，左上腹部輕壓痛，無反跳痛。實驗室檢查：血常規、血生化、AFP、CEA、CA19-9等均未見異常，尿淀粉酶1 547 U/L(正常值<1 000 U/L) 。CT顯示胰體尾交界區增大，可見斑片狀低密度區，大小約2.5 cm×3.7 cm，鄰近脾靜脈的邊緣不整。增強掃描后低密度區呈不均勻強化，其內未見強化壞死區(圖1a～c)。考慮：①腫瘤性病變；②炎癥性病變。擇期行剖腹探查術。術中見胰頭、頸部質軟，胰體尾部腫大，質硬，以胰尾為著，周圍未及腫大淋巴結。取活檢性病理檢查，報告為慢性胰腺炎。行胰體尾切除術。術后恢復順利，無胰瘺等并發癥發生。術后病理診斷為慢性胰腺炎(圖1d)。

討論局灶性胰腺炎是長期的慢性胰腺炎纖維化過程或急性炎癥后的復發性胰腺炎后形成的炎性腫塊[1]，臨床上常難于與胰腺癌進行鑒別[2]。

圖1 患者胰腺的CT征象(a～c)及手術切除標本的病理改變(d,HE ×200)

胰腺癌患者的血清CA19-9濃度升高，局灶性或彌漫性胰腺炎患者的血清CA19-9也可升高[3-4]，兩者的影像學表現也很類似。胰腺內存在假性囊腫或胰腺炎腫塊內有小囊腫并非局灶性胰腺炎胰腺腫塊的特征，因為任何阻塞性胰腺炎都可能合并假性囊腫形成[1，5]。CT鑒別慢性胰腺炎和胰腺癌準確率分別為53%和77%[6-7]，增強CT時，局灶性胰腺炎顯示為均勻或不均勻強化，大部分時間與其余腺體無明顯區別[1，8]。局灶型胰腺炎的峰值逐漸增強，而胰腺癌的峰值早期增強，此增強模式可以鑒別腫塊型胰腺炎與胰腺癌[9]。MRCP和ERCP檢查鑒別局限性胰腺炎與胰腺癌的依據是胰管的征象，遠端擴張的主胰管突然中斷更多見于胰腺癌[10]。

慢性胰腺炎或癌的診斷金標準是病理學或細胞學證據。內鏡超聲引導下細針穿刺是目前獲取胰腺組織樣本最好的方法，活檢標本病理診斷的敏感性、 特異性和準確性分別為80%～ 92%、100%和85%～95%[11-12]。檢測活檢組織的K-ras基因突變可進一步確定胰腺癌的診斷，但仍有假陰性的可能，這是因為胰腺癌組織中基因突變為非均質性或穿刺不能收集到足夠的胰腺癌標本[13]。

慢性胰腺炎是臨床難治性疾病，導致的頑固性疼痛和內外分泌功能不足或喪失及各種并發癥嚴重影響了患者的生活質量,同時也潛在著致癌因素。但對具體的患者選用何種術式才能達到好的治療效果,目前尚無可靠的數據或設計良好的隨機對照試驗研究來幫助外科醫師做出抉擇[14]。慢性胰腺炎的手術原則是胰管減壓和引流胰液或作病變部位胰腺組織的切除,并盡可能地保留內、外分泌功能。本例患者為局灶性胰腺炎，胰體尾部的炎性增生性改變應予以切除，選擇胰體尾切除是目前最為恰當的術式。

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