Ezrin immunohistochemical expression in cartilaginous tumours: a useful tool for differential diagnosis between chondroblastic osteosarcoma and chondrosarcoma.
ABSTRACT Ezrin is a cytoskeleton linker protein that is actively involved in the metastatic process of cancer cells. We have recently reported that ezrin expression in conventional osteosarcoma was an independent prognostic factor for event-free survival and overall survival. In this work, ezrin expression was found in all histological subtypes. Especially cartilaginous areas in chondroblastic osteosarcomas were immunopositive for ezrin. We wanted to know if ezrin could be a useful diagnostic marker in bone pathology. We have searched for ezrin expression in 208 cartilaginous tumours by immunohistochemistry and in 16 chondroblastic osteosarcomas. All conventional chondrosarcomas, whatever their grade, were negative, while ten of 16 chondroblastic osteosarcomas were positive. In contrast, dedifferentiated (five of 14) and mesenchymal chondrosarcomas (five of ten) showed ezrin positivity. Some chondroblastomas and more rarely chondromyxoid fibromas also exhibited ezrin expression. These data suggest that ezrin is a useful immunohistochemical marker for differential diagnosis between chondroblastic osteosarcomas and conventional chondrosarcomas with a specificity of 100%. Ezrin expression in dedifferentiated and mesenchymal chondrosarcomas which are aggressive neoplasms resistant to conventional treatment means that ezrin could be a therapeutic target. Ezrin expression in chondroblastomas is more intriguing and requires further study to assess prognostic value.
SourceAvailable from: Darrell R Borger[Show abstract] [Hide abstract]
ABSTRACT: Distinguishing chondrosarcoma from chondroblastic osteosarcoma can be difficult and highly subjective, especially on a small biopsy specimen. This distinction is critical in determining the most accurate prognosis and appropriate treatment modality, as adjuvant chemotherapy with surgery is standard treatment for osteosarcoma, whereas chondrosarcoma is generally treated by surgical excision alone. Cartilaginous neoplasms have recently been shown to frequently (56%) harbor gene mutations in the metabolic enzymes isocitrate dehydrogenase 1 (IDH1) and IDH2 (IDH1>IDH2), whereas other mesenchymal tumors lack these genetic aberrations. We investigated whether the presence of IDH1/2 mutations can be used to distinguish chondrosarcoma from chondroblastic osteosarcoma. Tumors including 25 predominantly high-grade chondrosarcomas and 65 osteosarcomas (44 chondroblastic osteosarcomas and 21 mixed osteosarcomas with a chondroblastic component) were evaluated, and a total of 59 cases (66%) were suitable for genotyping. Mutational analysis was performed using a multiplexed polymerase chain reaction genotyping platform to query for hotspot mutations in the genes IDH1 at codon R132. IDH1-negative cases underwent Sanger sequencing of IDH2 exon 4. No osteosarcomas (0/36) and 61% of chondrosarcomas (14/23) harbored a somatic mutation in IDH1/2, with the majority (86%) of mutations found in the IDH1 gene. IDH1/2 mutation analysis appears to be a promising biomarker for the distinction of chondrosarcoma from chondroblastic osteosarcoma. A positive result strongly favors the diagnosis of chondrosarcoma over chondroblastic osteosarcoma. The presence of IDH1/2 mutations can also help confirm the diagnosis of dedifferentiated chondrosarcoma when the tumor displays osteosarcomatous differentiation.The American journal of surgical pathology 04/2013; DOI:10.1097/PAS.0b013e31827ab703 · 4.59 Impact Factor
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ABSTRACT: Chondroblastic osteosarcoma (COS), a subgroup of intramedullary osteosarcoma (OS), is the most common osteosarcoma that occurs in adolescents and early adulthood. The COS has similar clinical and radiological features to those of conventional OS. We present a case of 20-year-old male patient with the chief complaint of pain and swelling in the left zygomatic region. The computed tomography (CT) and three-dimensional (3D) CT face showed erosion, calcific foci, sunray type of spicules suggestive of OS. On fine-needle aspiration cytology (FNAC) examination, initial diagnosis was malignant chondroid lesion, with differential diagnosis of mesenchymal chrondrosarcoma, COS on incisional biopsy and finally COS on excisional biopsy. The patient underwent radical resection of left zygomatic arch, followed by chemotherapy. Although clinically unsuspected in this unusual site, histopathology along with immunohistochemistry (IHC) results confirmed the COS. Because zygomatic location of COS is very rare, this report aimed to discuss clinical, radiographic, histopathologic, IHC findings and diagnostic pitfalls of COS in light of the literature.Journal of Oral and Maxillofacial Pathology 05/2014; 18(2):281-5. DOI:10.4103/0973-029X.140791
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ABSTRACT: Over the past decade, there have been remarkable advances in bone tumor pathology. Insights into the genetic basis and pathobiology of many tumor types have impacted diagnosis, classification, and treatment. However, because gnathic lesions may comprise only a small proportion of cases overall for many tumors, clinicopathologic features and management considerations specific to this subset may be overlooked. Here we provide a summary of recent developments in the following tumor types: osteosarcoma (OS), chondrosarcoma (CS), osteoid osteoma (OO), osteoblastoma (OB), and Ewing sarcoma (ES). In particular, we will give special consideration to cases arising in the jaws.Head and Neck Pathology 11/2014; DOI:10.1007/s12105-014-0587-8