婴幼儿先天性中胚层肾瘤的临床病理分析

The clinical and pathological analysis of congenital mesoblastic nephroma in infants

目的探讨婴幼儿先天性中胚层肾瘤的临床病理特点、诊断、鉴别诊断及预后。方法对11例婴幼儿先天性中胚层肾瘤患儿的临床及病理资料进行回顾性分析。结果男性9例,女性2例。发病年龄为胎儿~3岁。6例产前超声发现,4例因腹部包块就诊(2例伴血尿),1例CT检查无意中发现双肾占位。10例活产儿均可触及腹部肿块。影像学均显示肾占位病变,累及右肾及左肾各5例、双肾1例。10例行瘤肾根治切除术,1例为胎儿解剖资料。瘤体最大径约5.2 cm^17.0 cm,平均9.6 cm。大体呈灰白色实性,切面呈编织状或车辐状,部分见囊腔。镜下分为经典型(纤维瘤样)及富于细胞亚型(纤维肉瘤样),本组经典型8例,富于细胞亚型3例。免疫组化:瘤细胞表达Vimentin、SMA及HHF35;不表达WT1、上皮及横纹肌等标记。随访:1例富于细胞亚型者术后虽经化疗,但几乎每隔半年局部复发一次,共复发了7次,并多次重复手术及化疗,至今已随访3年余仍在化疗中;另2例富于细胞亚型者术后仅2周,未化疗,随访中。3例经典型仅术后密切随访,至今健在。4例经典型术后规律化疗,仍在随访中。结论本病主要见于<2岁婴幼儿,尤其是<3个月者。产前超声检查可明显提高检出率。应注意与肾母细胞瘤、肾透明细胞肉瘤及横纹肌样瘤等鉴别。预后较好,绝大多数患儿完整切除瘤肾即可治愈,尤其是经典型者。

Objective To explore the clinical and pathological features, diagnosis, differential diagnosis and prognosis of congenital mesoblastic nephroma （CMN） in infants. Methods Eleven patients with CMN were retrospectively reviewed. All tumor tissues were fixed with formalin and embed with paraffin and stained with HE and iminunohistoehemistry. Results There were 9 males among the 11 children. The cases were diagnosed from fetal stage up to 3 years old. Among the 11 cases, six cases were found by ultrasound prenatal when they were fetal; 4 cases were found because of the abdominal mass, of which two cases accompanied hematuria; one case was found by CT image. All cases had the palpable abdominal mass and the imaging finding showed renal occupied lesions. There were 5 cases occurred in the right kidney and 5 in the left, and one in the both kidneys. Surgical excisions were completed in 10 cases and one case was fetal anatomical data. The maximal diameter of tumor was 5.2 cm - 17.0 em and the mean diameter was 9.6 cm. Tumor was a solid lesion in grey-white color. The main pathological variants included the classic variant（ like fibroma）and cellular variant （like fibrosarcoma）. There were 8 cases of classic variant and 3 cellular variant. The tumor cells expressed Vimentin, SMA and HHF35, but didn＇t express WT1, CK and skeletal muscle markers with immunohistochemical staining. One case of the cellular variant occurred relapse 7 times after excision and did not respond to chemotherapy very well. The other 2 cases of cellular variant were followed-up after 2 weeks of operation. Three cases of classic variant only followed-up after excision. Four cases of classic variant followed- up constantly after regular chemotherapy. Conclusions CMN mostly occurs in infants less than 2 years old, especially less than 3 months. To use ultrasound examine during prenatal period can increase the detection rate. CMN usually had an excellent prognosis. Surgery was the main treatment method especially for classic variant. The differential diagnosis included nephroblastoma, clear cell sarcoma and rhabdoid tumor.