Department of Pathology, Maoming People's Hospital, Guangdong Medical University, Maoming City, China.
Department of Pathology, the First Affiliated Hospital of Zhengzhou University, Zhengzhou City, China.
Diagn Pathol. 2024 Jan 23;19(1):20. doi: 10.1186/s13000-024-01442-z.
Giant cell-rich solitary fibrous tumour (GCR-SFT), previously referred to as giant cell angiofibroma, is an uncommon soft tissue tumour that classically occurs in the orbit but very rarely presents in deep organs. Here, we present a case of GCR-SFT occurring in the urinary bladder, which is one of the unusual histological subtypes of SFT.
A 56-year-old man was incidentally found to have a mass measuring 4.5 × 4.3 × 4.0 cm located in the left posterior wall of the bladder by computed tomography during a physical examination. The lesion was confirmed as GCR-SFT by pathological examination after laparoscopic radical surgery. Histopathologically, the tumour was a well-circumscribed, nonencapsulated lesion that was composed of bland spindle-ovoid tumour cells alternating with hypocellular and hypercellular areas, staghorn-like vasculatures and scattered large dark-stained multinucleate giant cells lining pseudovascular spaces. The spindle-ovoid cells and multinucleate giant cells showed strong and diffuse expression of CD34 and nuclear STAT6. In addition, the hallmark of the NAB2ex4-STAT6ex5 fusion gene was detected by RT‒PCR. The patient was classified as having a low risk of recurrence or metastasis according to the risk stratification criteria. The patient underwent regular follow-up for 34 months after surgery, and there was no evidence of local recurrence or metastasis.
This is the first reported case of GCR-SFT occurring in the urinary bladder with underlying NAB2ex4-STAT6ex5 fusion. Complete surgical excision of the tumour and long-term follow-up are recommended to ensure no local recurrence or metastasis.
富含巨细胞的孤立性纤维性肿瘤（GCR-SFT），以前称为巨细胞血管纤维瘤，是一种罕见的软组织肿瘤，经典发生于眼眶，但很少发生于深部器官。本文报告了一例发生于膀胱的 GCR-SFT，这是 SFT 的一种不常见组织学亚型。
一名 56 岁男性在体检时行计算机断层扫描发现左膀胱后壁有一个 4.5×4.3×4.0cm 的肿块。经腹腔镜根治性手术后，病理检查证实为 GCR-SFT。组织病理学上，肿瘤边界清楚，无包膜，由温和的梭形卵圆形肿瘤细胞与细胞稀疏区和细胞丰富区、鹿角状血管和散在的大而深染的多核巨细胞交替组成，衬于假血管腔。梭形卵圆形细胞和多核巨细胞均强烈且弥漫表达 CD34 和核 STAT6。此外，通过 RT-PCR 检测到 NAB2ex4-STAT6ex5 融合基因的标志。根据风险分层标准，患者被归类为复发或转移风险低。患者术后定期随访 34 个月，未见局部复发或转移。
这是首例报道发生于膀胱的伴有 NAB2ex4-STAT6ex5 融合的 GCR-SFT。建议行肿瘤完全切除，并长期随访，以确保无局部复发或转移。
