促结缔组织增生性小圆细胞肿瘤临床病理特点及免疫组织化学分析

Clinicopathologic and immunohistochemical features of desmoplastic small round cell tumor

目的 探讨促结缔组织增生性小圆细胞肿瘤（DSRCT）的临床病理特点及免疫组化表型.方法 对6例DSRCT患者的临床特征、组织学形态及免疫组化表型进行研究,并复习了有关文献.结果 6例DSRCT中男性5例,女性1例,年龄19～44岁,平均29.8岁.发生于腹腔4例,其中2例同时有盆腔累及,以腹痛伴触及腹块就诊,1例发生于肺部,1例发生于睾丸及精索.肿瘤最大径范围5～10 cm,平均7.8 cm.镜下所见,肿瘤细胞呈大小不一、形状不规则的巢状排列,大的瘤巢中央可见坏死,肿瘤细胞核小而深染,胞质稀少,界限不清,核分裂象多,瘤巢之间为大量增生的纤维结缔组织.免疫组化显示所有病例均弥漫强阳性表达AE1/AE3、VIM及desmin,部分病例尚表达EMA、NSE、CD56、CGA、SYN、S-100及PLAP,无1例表达LCA及MyoD1.随访结果4例术后4～15个月（平均11个月）内死亡,2例分别带瘤生存1个月、20个月.结论 DSRCT为罕见、侵袭力强的高度恶性肿瘤,好发于年轻男性,大部分发生于腹腔及盆腔.瘤细胞具有神经、间叶和上皮标记复合表达,预后差.

Objective To study the clinicopathologic and immunohistochemical features of desmoplastic small round cell tumor （DSRCT）. Methods Six cases of DSRCT were investigated, the clinical features,pathological and immunohistochemical findings were described in details and the related literatures were reviewed. Results Among the 6 patients, 5 were males and one female,aged from 19 to 44 years （mean 29.8 years）. In 4 cases with neoplasm in abdominal peritoneum complained abdominal pain and physical examination showed a palpable abdominal mass. Pelvic peritoneum involvement was found in 2 cases,and one had additional lung involvement,another one had involvement of testicle and spermatic cord. The maximal diameter of tumor ranged from 5 to 10 cm （mean 7. 8 cm）. Histologically, the tumors were composed of sharply demarcated nests of varying size and irregular shape deposited in an abundant desmoplastic stroma. The central necrosis was often seen in large tumor nests ,the tumor cells appeared small and undifferentiated with inconspicuous nucleoli and abundant mitosis. Immunohistochemically,all cases showed diffuse and strong staining for AE1/AE3,VIM and desmin, some of them also expressed EMA,CD56,CGA,SYN,S-100 and PLAP and none for LCA and MyoD1. Follow-up showed that 4 cases died in 4-15 months （mean 11 months） after operation and the others were alive with tumors for 1 and 20 months,respectively. Conclusions This rare and aggressive neoplasm predominantly affects males and is almost intraabdominal in location. It is unique that neural,rnesenchymal and epithelial markers are co-expressed with poor prognosis.