Abstract：
Introduction Although nephroblastomas are frequently treated without prior biopsy, there are the occasional other pediatric renal tumors that require different management. In the literature, there are around 30 primary renal germ cell tumors (GCT), including four cases of Yolk sac tumor (YST). We present another primary renal YST.Case report: A five-year-old boy was diagnosed as Wilms tumor on radiology and needle biopsy. He received chemotherapy, with no response. The post-chemotherapy resection specimen revealed a YST.Conclusion: Renal YST may be indistinguishable from Wilms tumor clinically and radiologically. For pre-biopsy chemotherapy management protocols, serum tumor markers such as AFP may be recommended to identify the occasional GCT, including YST. Pre-chemotherapy needle biopsies may lead to misdiagnosis, and may require confirmation by an experienced pathologist or central review.
摘要：
简介尽管肾母细胞瘤经常在没有活检的情况下进行治疗，偶尔还有其他小儿肾脏肿瘤需要不同的治疗方法.在文学中,大约有30个原发性肾生殖细胞肿瘤（GCT），其中卵黄囊瘤(YST)4例。我们提出了另一个原发性肾YST。病例报告：一名5岁男孩在放射学和穿刺活检中被诊断为Wilms肿瘤。他接受了化疗,没有回应。化疗后切除标本显示YST。结论：肾YST在临床和放射学上可能与肾母细胞瘤没有区别。对于活检前化疗管理方案，血清肿瘤标志物如AFP可能被推荐用于识别偶尔的GCT，包括YST。化疗前穿刺活检可能导致误诊,并可能需要有经验的病理学家或中央审查的确认。
