胰腺实性-假乳头状肿瘤内PTEN和nestin的表达

Expression of PTEN and nestin in solid-pseudopapillary tumor of pancreas

目的探讨胰腺实体假乳头肿瘤(SPTP)细胞可能的组织学起源。方法复习25例SPTP的临床病理特征,常规HE和超微结构观察,免疫组化EnVision法染色检测肿瘤细胞PTEN和nestin等的表达。结果25例SPTP中女性22例,男性3例,中位年龄22·3岁。肿瘤主要位于胰腺内,1例位于后腹膜并与胰腺相连。1例伴有肝转移。肿瘤呈囊实性,出血、坏死明显。肿瘤细胞大小形态较一致,实性和假乳头状排列,部分似“室管膜样”菊形团。核卵圆形,有核沟,核仁不明显,核分裂象少见。肿瘤细胞均有PTEN阳性表达(18/18,100%),44%(8/18)的病例有nestin的表达。超微结构观察细胞内可见酶原样分泌颗粒和神经内分泌颗粒。结论胰腺实体假乳头肿瘤可能起源于胰腺多能干细胞。

Purpose To explore the possible origin of histological in solid-pseudopapillary tumor（SPTP） of the pancreas. Methods 25 cases of SPTP were observed by light microscopy and immunohistochemical staining. 7 cases were investigated with electron microscopy. Results Tumors consisted of 3 males and 22 females. 23 cases situated in the pancreas and 1 case in the retroperitoneum adjacent to the pancreas. One patient presented with metastases to the liver. Gross examination typically revealed a hemorrhagic-cystic tumor surrounded by a well-formed fibrous capsule. Microscopically, the tumors exhibited both a sold pattern and a pseudopapillary pattern. Neoplastic cells arranged radially around the minute fibrovascular stalk resembling ＂ependymal＂ rosettes. The tumor cells were small to medium-sized and polygonal or elongated, with ovoid nuclei that were grooved or indented. Nucleoli were inconspicuous and mitotic figures were rare. Tumor cells were typically positive for PNET （ 18/18, 100% ）, and 44% for nestin （8/18,）. 21 cases had survived for 3 -72 months. Conclusion The SPTP may come from multipotential cells of the pancreas.