Grove John, Naous Rana
Pathology and Laboratory Medicine, University of Pittsburgh Medical Center, Pittsburgh, USA.
Pathology, University of Pittsburgh Medical Center, Pittsburgh, USA.
Cureus. 2025 May 31;17(5):e85154. doi: 10.7759/cureus.85154. eCollection 2025 May.
-rearranged sarcomas are rare, high-grade, undifferentiated, small round cell sarcomas of bone and soft tissue classified by gene fusions involving the gene with other gene partners, most commonly the gene. These tumors tend to affect a wide age range, with a predilection for adult males, with the most common anatomical location being the deep soft tissues of the limbs or trunk. -rearranged sarcomas have proven not only to be challenging to diagnose but also to treat due to their high resistance to conventional therapies. Preferentially expressed antigen in melanoma (PRAME) is an immunohistochemical stain that was developed primarily for the diagnosis of melanoma and has been shown to also be expressed in other epithelial and mesenchymal tumors. To date, PRAME immunopositivity has not been reported in -rearranged sarcomas. Here, we report a 51-year-old male with a large gluteal undifferentiated small round cell sarcoma and bilateral lung metastases, whereby RNA sequencing confirmed the tumor as sarcoma. Interestingly, the sarcoma demonstrated very strong PRAME immunohistochemical positivity, a diagnostic finding that has not yet been reported on sarcomas and has potential use as a beneficial tool in the workup of a diagnostically challenging disease.
-重排肉瘤是罕见的、高级别、未分化的骨和软组织小圆细胞肉瘤，通过涉及该基因与其他基因伙伴（最常见的是基因）的基因融合进行分类。这些肿瘤倾向于影响广泛的年龄范围，以成年男性为主，最常见的解剖位置是四肢或躯干的深部软组织。-重排肉瘤已被证明不仅诊断具有挑战性，而且由于其对传统疗法的高度抗性，治疗也很困难。黑色素瘤优先表达抗原（PRAME）是一种免疫组织化学染色，主要用于黑色素瘤的诊断，并且已显示在其他上皮和间叶肿瘤中也有表达。迄今为止，尚未报道PRAME免疫阳性在-重排肉瘤中的情况。在此，我们报告一名51岁男性，患有巨大的臀部分化不良小圆细胞肉瘤并伴有双侧肺转移，通过RNA测序证实该肿瘤为肉瘤。有趣的是，该肉瘤显示出非常强的PRAME免疫组织化学阳性，这一诊断发现尚未在肉瘤中报道，并且在诊断具有挑战性的疾病的检查中具有作为有益工具的潜在用途。
