Kiel Pediatric Tumor Registry, Department of Pediatric Pathology, Christian-Albrechts-University Kiel, Kiel, Germany.
Department of Pediatric Hematology and Oncology, University Medical Center Homburg/Saar, Homburg, Germany.
Pediatr Blood Cancer. 2018 Apr;65(4). doi: 10.1002/pbc.26925. Epub 2017 Dec 29.
Congenital mesoblastic nephroma (MN) is a rare pediatric renal tumor representing approximately 5% of all pediatric renal tumors. Three different types of MN are distinguished histologically: classical, cellular, and mixed. A frequent genetic alteration is the translocation t(12;15) resulting in a fusion of the ETV6 gene on 12p13 and the NTRK3 gene on 15p15 that occurs almost exclusively in cellular MN. The aim of this study was to determine translocation status of a large cohort of MN with respect to tumor subtype and outcome.
In total, clinical data from 111 patients were available. Sixty-seven tumors were classical MN (51%), 29 cellular MN (31%), and 15 were mixed MN (18%). From these 111 cases, 79 were analyzed by FISH and RT-PCR.
All classical and mixed MN were translocation negative. Seventeen out of 29 (58%) cellular MN harbored the ETV6-NTRK3 translocation. Five-year relapse-free survival (RFS) and overall survival (OS) were 93.2% and 96.8% for the complete cohort. All seven relapses occurred in translocation negative tumors. Five-year RFS was significantly inferior for cellular and mixed MN compared to classic MN (89%, 80%, and 98%), whereas 5-year OS was similar (93%, 96%, and 98%). Within the group of cellular MN, patients having translocation-positive tumors had a significantly superior RFS (5-year RFS: 100% vs. 73%).
The majority of cellular MNs harbor the ETV6-NTKR3 gene fusion, whereas all classic- and mixed-type MNs were translocation negative. Within the cellular subgroup, patients having translocation-positive tumors had a significantly superior RFS.
先天性中胚层肾瘤（MN）是一种罕见的儿科肾肿瘤，约占所有儿科肾肿瘤的 5%。MN 在组织学上可分为三种不同类型：经典型、细胞型和混合型。一种常见的遗传改变是易位 t(12;15)，导致 12p13 上的 ETV6 基因和 15p15 上的 NTRK3 基因融合，这种融合几乎只发生在细胞型 MN 中。本研究的目的是确定 MN 的大样本肿瘤亚型和预后的易位状态。
共获得 111 例患者的临床资料。67 例肿瘤为经典 MN（51%），29 例为细胞型 MN（31%），15 例为混合 MN（18%）。从这 111 例中，79 例通过 FISH 和 RT-PCR 进行了分析。
所有经典型和混合型 MN 均为易位阴性。29 例细胞型 MN 中有 17 例（58%）存在 ETV6-NTRK3 易位。全组 5 年无复发生存率（RFS）和总生存率（OS）分别为 93.2%和 96.8%。所有 7 例复发均发生在无易位的肿瘤中。与经典 MN 相比，细胞型和混合型 MN 的 5 年 RFS 显著降低（89%、80%和 98%），而 5 年 OS 相似（93%、96%和 98%）。在细胞型 MN 组中，携带易位阳性肿瘤的患者的 RFS 显著更高（5 年 RFS：100% vs. 73%）。
大多数细胞型 MN 携带 ETV6-NTKR3 基因融合，而经典型和混合型 MN 均为易位阴性。在细胞型亚组中，携带易位阳性肿瘤的患者的 RFS 显著更高。
