Hasegawa T, Shimoda T, Yokoyama R, Beppu Y, Hirohashi S, Maeda S
Pathology Division, National Cancer Center Research Institute, Tokyo, Japan.
Skeletal Radiol. 1999 Jan;28(1):41-5. doi: 10.1007/s002560050470.
Intracortical osteosarcoma is the rarest variant of osteosarcoma, occurring within, and usually confined to, the cortical bone. Oncogenic osteomalacia, or rickets, is an unusual clinicopathologic entity in which vitamin D-resistant osteomalacia, or rickets, occurs in association with some tumors of soft tissue or bone. We present a case of oncogenic rickets associated with intracortical osteosarcoma of the tibia in a 9-year-old boy, whose roentgenographic abnormalities of rickets disappeared and pertinent laboratory data except for serum alkaline phosphatase became normal after surgical resection of the tumor. Histologically, the tumor was an osteosarcoma with a prominent osteoblastic pattern. An unusual microscopic feature was the presence of matrix mineralization showing rounded calcified structures (calcified spherules). Benign osteoblastic tumors, such as osteoid osteoma and osteoblastoma, must be considered in the differential diagnosis because of the relatively low cellular atypia and mitotic activity of this tumor. The infiltrating pattern with destruction or engulfment of normal bone is a major clue to the correct diagnosis of intracortical osteosarcoma. The co-existing radiographic changes of rickets were due to the intracortical osteosarcoma.
皮质内骨肉瘤是骨肉瘤中最罕见的变异类型，发生于皮质骨内，通常局限于皮质骨。致癌性骨软化症或佝偻病是一种不寻常的临床病理实体，其中维生素D抵抗性骨软化症或佝偻病与一些软组织或骨肿瘤相关。我们报告一例9岁男孩，其患有与胫骨皮质内骨肉瘤相关的致癌性佝偻病，在肿瘤手术切除后，其佝偻病的X线异常消失，除血清碱性磷酸酶外的相关实验室数据恢复正常。组织学上，肿瘤为具有显著成骨细胞模式的骨肉瘤。一个不寻常的微观特征是存在显示圆形钙化结构（钙化小球）的基质矿化。由于该肿瘤细胞异型性相对较低且有丝分裂活性较低，在鉴别诊断中必须考虑良性成骨细胞肿瘤，如骨样骨瘤和成骨细胞瘤。正常骨的破坏或包绕的浸润模式是正确诊断皮质内骨肉瘤的主要线索。同时存在的佝偻病影像学改变是由皮质内骨肉瘤引起的。
