Department of Pathology, Beijing Jishuitan Hospital, The Fourth Medical College of Peking University, 100035, Beijing, China.
Department of orthopedic oncology, Beijing Jishuitan Hospital, The Fourth Medical College of Peking University, 100035, Beijing, China.
Diagn Pathol. 2022 Oct 13;17(1):80. doi: 10.1186/s13000-022-01263-y.
Recently, a novel group of CD34 and S100 co-expression spindle cell tumors with distinctive stromal and perivascular hyalinization harboring recurrent gene fusions involving RET, RAF1, BRAF, and NTRK1/2 gene has been identified.
In this study, we reported two Chinese male patients with soft tissue tumors presenting in the right knee joint and the left thigh, respectively. For both patients, the tumors were completely excised with clear margin. Microscopically, case 1showed morphological overlap with neurofibroma, and case 2 showed overlap with lipomatous solitary fibrous tumor. Both tumors showed co-expression of S100 and CD34, and absence of SOX10. Genomic profiling with DNA-based next-generation sequencing (NGS) assay was performed and revealed KIF5B-RAF1 (K16:R8) and TLN2-RAF1 (T54:R8) rearrangements. RNA-based NGS and RT-PCR were performed to confirm the gene fusion.
Though systemic therapy was not indicated in these two patients, identification of targetable kinase fusions may help to refine tumors with an ambiguous immunoprofile, and provides suggestions for targeted therapy in rare aggressive cases.
最近，一组新型的 CD34 和 S100 共表达梭形细胞肿瘤被鉴定出来，这些肿瘤具有独特的基质和血管周围玻璃样化，包含涉及 RET、RAF1、BRAF 和 NTRK1/2 基因的复发性基因融合。
在本研究中，我们报告了两名中国男性患者，他们分别患有位于右膝关节和左大腿的软组织肿瘤。对于这两名患者，肿瘤均通过清晰的边界进行了完全切除。显微镜下，病例 1 显示与神经纤维瘤形态重叠，病例 2 显示与脂肪瘤性孤立性纤维性肿瘤重叠。两个肿瘤均显示 S100 和 CD34 的共表达，以及 SOX10 的缺失。对 DNA 为基础的下一代测序（NGS）检测进行了基因组分析，结果显示 KIF5B-RAF1（K16：R8）和 TLN2-RAF1（T54：R8）重排。进行 RNA 为基础的 NGS 和 RT-PCR 以确认基因融合。
虽然这两名患者不需要系统治疗，但鉴定出可靶向的激酶融合可能有助于明确免疫表型不明确的肿瘤，并为罕见的侵袭性病例提供靶向治疗建议。
