以骨肉瘤形态为主的原发性恶性骨巨细胞瘤7例临床病理分析

Primary malignant giant cell tumor of bone with predominant osteosarcoma morphology:a clinicopathological analysis of seven cases

目的探讨以骨肉瘤形态为主原发性恶性骨巨细胞瘤(primary malignant giant cell tumor of bone,PMGCTB)的临床病理学特征。方法回顾性分析7例PMGCTB的临床病理特征。结果7例PMGCTB中,女性4例,男性3例,年龄9~66岁(平均39.5岁,中位年龄35岁)。发生部位以股骨骨端最常见(3/6),临床表现为病变部位的疼痛和肿胀。影像学表现为溶骨性占位、溶骨和硬化混合性占位为主;多数骨皮质破坏伴软组织肿块形成(5/7)。组织学均以普通型骨肉瘤形态为主,破骨细胞样多核巨细胞完全消失或少量存在。免疫表型:6例肿瘤细胞H3F3A G34W核阳性、1例H3F3A G34V核阳性,所有肿瘤均表达SATB2、p63,p53呈野生型,Ki67增殖指数10%~50%。所有病例均发现H3F3A基因改变,6例为H3F3A p.G34W突变,1例为H3F3A p.G34V突变。结论PMGCTB罕见,当缺乏经典骨巨细胞瘤组织学特征时诊断更具挑战性,需结合影像学、免疫表型及分子检测,并注意与骨肉瘤及其他高级别肉瘤相鉴别。

Purpose To elucidate the clinicopathological characteristics of primary malignant giant cell tumor of bone(PMGCTB)with mainly osteosarcoma-like morphology.Methods Clinicopathologic features of 7 cases of PMGCTB were ret-[CD44]rospectively analyzed.Results Among 7 patients with PMGCTB,there were 4 females and 3 males,aged between 9 and 66 years(mean age 39.5 years,median age 35 years).The distal femur emerged as the most frequent site to be involved(3/6).The main clinical manifestations included pain and swelling at the original site of the tumor.Radiological findings indicated osteolytic lesions,often combined with sclerotic areas;most cases showed cortical bone destruction and soft tissue masses(5/7).Histologically,the majority of tumors exhibited typical morphological features of osteosarcoma with a few or without osteoclast-like multinucleated giant cells.Positive immunoreaction with H3F3A G34W was confirmed in 6 cases and with H3F3A G34V in 1 case.SATB2 and p63 were positive in all cases,p53 was proved to be wild type,the Ki67 proliferation index ranged approximately from 10%to 50%.H3F3A p.G34W mutation was detected in 6 cases and only 1 case harboring H3F3A p.G34V mutation.Conclusion PMGCTB is exceedingly rare and difficult for accurate diagnosis,especially for those with atypical morphological features.A comprehensive analysis involving radiological,immunophenotypic,and molecular detection is necessary to rule out other high-grade sarcomas.