Dedifferentiated chondrosarcoma

We reviewed 74 cases of dedifferentiated central and peripheral chondrosarcoma. Histologically these tumours consist of an underlying cartilaginous component (either benign or malignant) juxtaposed to a highgrade non-cartilaginous component, with a typically abrupt transition between the two tissue types. The noncartilaginous component may constitute a very small or a very large proportion of the tumour, so diagnosis often requires histological evaluation of the entire tumour. The diagnosis is often suspected on the basis of the clinical course and careful evaluation of the radiographie characteristics. Central dedifferentiated chondrosarcoma can be classified radiographically into three types. In type 1 (36 cases in our review) the radiographie features are the same as those of a central chondrosarcoma, with the addition of a region with very aggressive radiographie features. Type 2 lesions (20 cases) resemble the underlying benign enchondroma but also have destructive changes and/or a large soft tissue mass. Type 3 lesions (8 cases) are not distinctive radiographically and present as a very high grade destructive lesion of bone. These cases are diagnosed following biopsy or tumour resection. The prognosis of these tumours is extremely poor, with 13% overall 5-year survival in this series. Improved survival was found in those cases where diagnosis was prompt and surgical treatment with a wide or radical margin was attained. No benefit was found from the use of adjuvant chemotherapy or radiotherapy. Thus, early recognition of the characteristic radiographie features, adequate histological sampling, and wide or radical surgical margins are necessary for satisfactory management of this highly malignant variant of chondrosarcoma.     

Benign giant cell tumor of bone with osteosarcomatous transformation (”dedifferentiated” primary malignant GCT): report of two cases

 It is not uncommon for sarcomatous transformation of giant cell tumor (GCT) of bone to occur after radiation, but rarely does malignant transformation occur spontaneously, with less than 15 cases reported up to 1995. Only four of these cases have been documented in detail. We report two additional cases of GCT of bone spontaneously transforming or ”dedifferentiating” into osteosarcoma without radiation therapy. The first case is absolutely unique and most interesting in that the dedifferentiation process occurred in one of multiple GCT lung metastases 6 years after successful eradication of a primary tibial tumor. The right lung was resected due to development of a large tumor, and at pathologic examination, demonstrated several small nodules of conventional GCT and a much larger, 14-cm mass composed of a mixture of GCT and high-grade osteosarcoma. The second case involved a physician, who had a large tumor in the sacrum with vague symptoms for 8 years. Open biopsy revealed conventional, benign GCT of bone with a secondary aneurysmal bone cyst. Complete curettage 2 weeks later revealed, in addition to areas of conventional, benign GCT a second component of very high grade osteosarcoma. Both patients died less than 1.5 years from diagnosis. This report of osteosarcomatous transformation of a conventional GCT of bone strengthens the theory that there is a mesenchymal cell line in GCT that may spontaneously tansform to sarcoma.     

维生素C提高体外培养的去分化脂肪细胞心肌分化效率

目的:采用维生素C处理体外培养的去分化脂肪(dedifferentiated fat,DFAT)细胞,以期进一步提高DFAT细胞的心肌分化效率。方法:用天花板贴壁培养法使大鼠成熟脂肪细胞去分化为DFAT细胞,并体外培养增殖至第3代,然后在培养基中添加维生素C或(和)乳鼠心脏细胞裂解液诱导DFAT细胞心肌分化。3周后,用倒置相差显微镜观察DFAT细胞的形态变化,用real-time PCR、免疫荧光和Western blot检测DFAT细胞的心肌特异性标志物c Tn T、GATA-4及NKx2.5 mRNA和蛋白的表达。结果:大鼠脂肪细胞经天花板贴壁培养后形态转变为成纤维细胞样的DFAT细胞。DFAT细胞在普通培养条件下可自发表达少量心肌特异性标志物。经乳鼠心脏细胞裂解液诱导后,DFAT细胞体积增大、变长,可见肌管样结构,c Tn T、GATA-4及NKx2.5 mRNA和蛋白的表达水平较普通培养的DFAT细胞显著升高。在维生素C的作用下,DFAT细胞c Tn T、GATA-4及NKx2.5的表达水平进一步升高。未观察到自发性搏动细胞。结论:维生素C可促进DFAT细胞分化为心肌样细胞。     

Dedifferentiated liposarcoma of the spermatic cord with a hemangioendothelioma-like component: A case report and review of the literature

Atypical lipomatous tumor or well-differentiated liposarcoma/dedifferentiated liposarcoma (DDLPS) is the most frequent subtype of malignant adipocytic tumor. This tumor typically presents in late adult life, most commonly in the retroperitoneum, extremities, or spermatic cord. It has been reported that the dedifferentiated component consists mainly of high-grade sarcoma, including undifferentiated pleomorphic sarcoma, fibrosarcoma, and myxofibrosarcoma, and it has been recently reported that the dedifferentiated component can be also made up of a low-grade sarcomatous component. Therefore, the dedifferentiated areas exhibit a wide morphological spectrum that commonly includes fibroblastic/myofibroblastic and fibrohistiocytic tumors but very rarely includes vascular tumors. We present here the first reported case of DDLPS with a hemangioendothelioma-like component in the spermatic cord.     

Combining surgery with 125I brachytherapy for recurrent mediastinal dedifferentiated liposarcoma: A case report and review of literature

BACKGROUND Dedifferentiated liposarcoma in the mediastinum is an extremely rare malignant neoplasm.A few previous case reports indicate that surgical resection is the major treatment,but frequent recurrence occurs locally.Due to its rarity,its clinical characteristics,optimal treatment and clinical outcomes remain unclear.Here,we report a case of multifocal recurrent dedifferentiated liposarcoma in the posterior mediastinum treated by combining surgery with 125I brachytherapy,and summarize its clinical features,treatment and prognosis.CASE SUMMARY A 75-year-old man was admitted to our hospital with a history of gradual dysphagia for one year and aggravated dysphagia for 3 mo.Contrast-enhanced computed tomography(CT)revealed several large cystic-solid masses with lipomatous density,and calcification in the posterior-inferior mediastinum.The patient received a wide excision by video-assisted thoracoscopic surgery.Pathological analysis confirmed the tumors were dedifferentiated liposarcomas.The tumor locally relapsed 24 mo later,and another operation was performed by video-assisted thoracoscopic surgery.Fifteen months after the second surgery,the tumor recurred again,and the patient received CT-guided radioactive seeds 125I implantation.After 8 mo,follow-up chest CT showed an enlarged tumor.Finally,his condition exacerbated with severe dysphagia and dyspnea,and he died of respiratory failure in July 2018.CONCLUSION We reviewed the literature,and suggest that surgical resection provides beneficial effects for dedifferentiated liposarcoma in the mediastinum,even in cases with local recurrence.125I brachytherapy may be beneficial for recurrent unresectable patients.     

基因芯片筛选软骨肉瘤去分化相关基因初步探讨

目的：探讨用基因芯片技术区分普通型软骨肉瘤与去分化软骨肉瘤组织中基因的差异表达。方法：对病理证实的普通型软骨肉瘤及去分化软骨肉瘤组织,提取细胞mRNA,用寡核苷酸芯片,与正常关节软骨组织杂交后获得荧光信号,计算机软件分析荧光信号结果,并对数据进行归一化处理,分析组间显著变化的基因,然后对其进行聚类和主成份分析,筛选出差异表达的基因。结果：在所检测的人普通型软骨肉瘤与去分化软骨肉瘤组织中,31个基因有表达异常,其中高表达14条,低表达17条。结论：去分化软骨肉瘤与普通型软骨肉瘤间基因表达差异是明显的,这些差异基因主要分布于涉及TGT信号途径、Wnt信号途径、IHH/PThRP轴以及凋亡机制等多方面,且有些基因的作用目前尚不清楚。     

去分化皮质旁骨肉瘤

目的 探讨去分化皮质旁骨肉瘤(Dedifferentiated parosteal osteosarcoma,dd-POS)的临床特点及其治疗。方法 回顾5例dd-POS的临床、影像和组织学资料,总结出dd-POS的临床病理学特点、治疗及其预后。结果 5例患者中3例分别于术后21个月、25个月和31个月死于肺转移,2例无瘤存活50个月和72个月,其中1例在术后1年局部复发,经再次手术得以控制。结论 虽然dd-POS的诊断最终有赖于组织学检查,但影像资料是早期鉴别高度恶性变区最有效的方法。