Bertoni Franco, Bacchini Patrizia, Staals Eric L
Istituto Ortopedico Rizzoli, Bologna, Italy.
Cancer. 2003 May 15;97(10):2520-9. doi: 10.1002/cncr.11359.
The term malignant giant cell tumor embraces multiple entities and therefore can be confusing. The goals of the current study were to define the clinicopathologic and histologic features of malignancy in giant cell tumors and to clarify the terminology.
The authors reviewed all cases from the Rizzoli Institute (Bologna, Italy) of primary (PMGCT) and secondary (SMGCT) malignancy in giant cell tumors. PMGCT is a high-grade sarcoma that arises side by side with benign giant cell tumors. SMGCT is a high-grade sarcoma that occurs at the sites of previously treated giant cell tumors of bone.
The authors report 5 PMGCTs and 12 SMGCTs; half of the SMGCTs were postradiation sarcomas. Patient age ranged from 20 to 68 years (median, 62 years) for PMGCT and from 30 to 77 years (median, 40 years) for SMGCT. The average latent period between diagnosis of giant cell tumor and diagnosis of SMGCT was 9 years (range, 3-15 years) for patients with postradiation SMGCT and 19 years (range, 7-28 years) for patients with SMGCT resulting from spontaneous transformation. The histologic classification of high-grade sarcomas in the PMGCT group was osteosarcoma in four cases and malignant fibrous histiocytoma in one case. In the SMGCT group, the histologic classification was osteosarcoma in nine cases, fibrosarcoma in two cases, and malignant fibrous histiocytoma in one case. The outcomes associated with all malignancies in giant cell tumors were poor, with the worst outcome associated with postradiation SMGCT.
Malignancies in giant cell tumors of bone always are high-grade sarcomas with a poor prognosis. These lesions must be distinguished from benign giant cell tumors of bone. SMGCT usually is easy to diagnose upon malignant clinicoradiographic presentation. In contrast, PMGCT often mimics giant cell tumors both clinically and radiographically. In addition, upon histologic examination, PMGCT shows areas of conventional giant cell tumor, which can lead to difficulties in making the correct diagnosis.
恶性巨细胞瘤这一术语包含多种实体，因此可能会造成混淆。本研究的目的是明确巨细胞瘤恶性病变的临床病理和组织学特征，并阐明相关术语。
作者回顾了意大利博洛尼亚里佐利研究所所有原发性（PMGCT）和继发性（SMGCT）巨细胞瘤恶性病变的病例。PMGCT是一种高级别肉瘤，与良性巨细胞瘤并存。SMGCT是一种高级别肉瘤，发生于先前治疗过的骨巨细胞瘤部位。
作者报告了5例PMGCT和12例SMGCT；其中一半的SMGCT是放疗后肉瘤。PMGCT患者年龄范围为20至68岁（中位年龄62岁），SMGCT患者年龄范围为30至77岁（中位年龄40岁）。放疗后SMGCT患者从骨巨细胞瘤诊断到SMGCT诊断的平均潜伏期为9年（范围3至15年），自发转化导致的SMGCT患者平均潜伏期为19年（范围7至28年）。PMGCT组高级别肉瘤的组织学分类为骨肉瘤4例，恶性纤维组织细胞瘤1例。SMGCT组组织学分类为骨肉瘤9例，纤维肉瘤2例，恶性纤维组织细胞瘤1例。骨巨细胞瘤所有恶性病变的预后均较差，放疗后SMGCT的预后最差。
骨巨细胞瘤的恶性病变均为高级别肉瘤，预后不良。这些病变必须与骨良性巨细胞瘤相鉴别。SMGCT通常在出现恶性临床影像学表现时易于诊断。相比之下，PMGCT在临床和影像学上常与巨细胞瘤相似。此外，在组织学检查中，PMGCT显示有传统巨细胞瘤区域，这可能导致正确诊断困难。
