中间型滋养细胞肿瘤的临床病理分析

目的探讨中间型滋养细胞（IT）源性肿瘤即胎盘部位滋养叶细胞肿瘤（PSTT）及上皮样滋养细胞肿瘤（ETT）临床病理特征及免疫表型表达特点、诊断与预后。方法北京妇产医院1959-2005年中,因恶性滋养叶疾病住院治疗患者共1012例,从中筛选6例PSTT及1例ETT,对其临床特征、病理诊断要点及免疫组织化学（SP法）结果进行分析,抗体包括CK18、胎盘催乳素（hPL）、人绒毛膜促性腺激素（hCG）、Mel—CAM（CDl46）及胎盘碱性磷酸酶（PLAP）。对照组为20例附有底蜕膜的早期绒毛及20例见有着床部位反应的葡萄胎。结果平均年龄PSTT为32．4岁,ETT为36岁;症状主要为阴道不规则出血和闭经;术前检查hCG呈正常→轻度→中度增高趋势,1例睾酮明显增高。5例PSTT术前行刮宫及宫腔镜切取标本之确诊率为3／5。镜下PSTT瘤细胞呈单个、条索状或片状浸润于肌纤维间,将单个或一束肌纤维分离;ETT则显示岛屿状细胞群位于玻璃样物及坏死物中,呈地图样结构。治疗手段以子宫切除术或术后辅以化疗为主。随访时间14个月至19年,其中1例PSTT术后5个月发生胰腺转移,单纯化疗PSTT患者疗效尚不能肯定,其余均无复发。结论PSTT与ETT分别为发生于着床部位IT及绒毛膜类型IT,二者有不同病理形态学,免疫组织化学特征性表达可辅助诊断和鉴别诊断;术前诊断性刮宫病理诊断具有重要临床意义;PSTT与ETT显示相同的生物学行为和预后。

Clinicopathologic study of tumors of intermediate trophoblasts

Objective To study the clinicopathologic features and immunophenotype of placental site trophoblastic tumor (PSTT) and epithelioid trophoblastic tumor (ETT). Methods During the period from 1959 to 2005, a total of 1012 cases of gestational trophoblastic disease were diagnosed in Beijing Obstetrics and Gynecology Hospital. Six cases of PSTT and a case of ETT were retrieved from the archives of Beijing Obstetrics and Gynecology Hospital. Immunohistochemical study for cytokeratin 18, human chorionic gonadotropin (hCG), human placental lactogen (hPL), Mel-CAM (CD146), placental-like alkaline phosphatase (PLAP), epithelial membrane antigen (EMA), inhibin-alpha and proliferative cell nuclear antigen (PCNA) were performed. The morphologic features and immunohistochemical findings were compared with those of the controlled group which consisted of 20 cases of early gestational villi with decidua basalis and 20 cases of hydatidiform moles with implantation site. Results The mean age of patients with PSTT was 32.4, while the age of patients with ETT was 36. Major clinical findings included irregular vaginal bleeding and amenorrhea. Preoperative serum hCG level varied from normal to moderately elevated. Serum testosterone level was raised in 1 case. Uterine curettage could achieve an accurate pathologic diagnosis in 60% of cases. ETT involved mainly the lower uterine segment and endocervix. Histologically, PSTT cells permeated between the myometrial fibers and vessels either individually or connecting in cords or sheets in a manner reminiscent of the implantation site reaction. ETT composed of a relatively uniform population of mononuclear trophoblastic cells, clumping together in nests as the cell islets associating with eosinophilic, fibrillary and hyaline material and necrotic debris, forming a "geographic map" like pattern. Immunohistochemical study for hPL, hCG, Mel-CAM (CD146) and PLAP was most helpful for the differential diagnosis. The duration of follow-up varied from 14 months to 19 years. One case of PSTT developed metastasis in pancreas, 5 months after the operation. The remaining patients survived without tumor recurrence. Conclusions PSTT is a tumor of implantation site intermediate trophoblasts while ETT differentiates towards chorionic-type intermediate trophoblasts. The different pathologic features and immunophenotype observed were closely related with the difference in tumor cell differentiation. An accurate pathologic diagnosis of the uterine curettage material is important for the clinical management. According to the limited follow-up data available, the clinical behavior of ETT is seemed similar to that of PSTT.