Rosette-forming epithelioid osteosarcoma: a histologic subtype with highly aggressive clinical behavior

Clinical and Pathological Features of Osteosarcomas of the Jaws: A Retrospective Study

INTRODUCTION

Osteosarcomas of the jaw (OSJs) are rare tumors with distinct characteristics from osteosarcomas affecting other bones. This study aims to analyze the clinical, pathological, and therapeutic characteristics of OSJs.

METHODS

A retrospective, descriptive cross-sectional study including patients diagnosed with OSJ registered at the "La Paz" University Hospital, Madrid, was performed.

RESULTS

Data of eight patients with a diagnosis of OSJ were obtained during the study period of 22 years (2002-2024). The mean age of the patients was 41 years. The distribution was 1:1 between the maxilla and mandible. Painful inflammation was the most frequent clinical manifestation. Conventional osteoblastic osteosarcoma was the most predominant histological type. Survival rate at 5 years was 50%, which decreased to 25% at 10 years.

CONCLUSIONS

OSJs differ from conventional osteosarcomas of long tubular bones. Surgery continues to be the mainstay of treatment. However, more studies are needed through which more standardized protocols can be proposed for adjuvant therapeutic management.

Rosette-forming epithelioid osteosarcoma in the rib: a rare case of location and morphology

The rib is an unusual location for osteosarcoma and is reported in only 2% of all cases. The major histological variants of osteosarcoma are osteoblastic, chondroblastic, and fibroblastic, with a few rare variants including one epithelioid type. This report describes a 44-year-old male with an osteolytic mass in the right seventh rib. Histological examination revealed osteosarcoma with unique features of epithelioid appearance and rosette structures. To the best of our knowledge, this is the first reported case of a rosette-forming osteosarcoma of the rib that showed epithelioid morphology. Despite successful surgery, the patient’s prognosis was poor because this malignancy had an unusual location within the axial skeleton and was a rare histological variant.

Cytokeratin-Positive Osteosarcoma Simulating Sarcomatoid Metastatic Carcinoma

Osteosarcoma, the most common primary malignant bone tumor, rarely stains positive for epithelial markers such as cytokeratin on immunohistochemical analysis. We describe a 52-year-old man with a destructive distal femoral metaphyseal lesion who was initially treated for metastatic sarcomatoid carcinoma based on extensive radiographic and histopathologic evaluation. Ultimately, wide resection of the distal femur was performed, revealing high-grade conventional osteosarcoma with intense and diffuse cytokeratin positivity. Such immunohistochemical staining in osteosarcoma is rare, making it difficult to distinguish cytokeratin-positive osteosarcoma from metastatic carcinoma. The presence of a cytokeratin-positive bone neoplasm with malignant osteoid formation on histological studies as well as integration with clinical and radiologic data can help confirm osteosarcoma as the ultimate diagnosis.

Metachronous extraskeletal (soft tissue) epithelioid osteogenic sarcoma: a case report

Background

Metachronous osteosarcoma is a rare form of osteosarcoma. The occurrence of metachronous tumor in soft tissue is exceedingly rare. The pathogenesis of metachronous osteosarcoma, as to whether it represents multiple true primaries or metastatic disease, is still obscure.

Case presentation

A 49-year-old Indian man presented with progressively increasing swelling in his left hand of 2 months’ duration. An X-ray showed a soft tissue lesion. Contrast-enhanced computed tomography showed a soft tissue mass lesion, with peripheral enhancement and central necrotic areas in radial palmar soft tissue overlying second metacarpophalangeal region with no obvious bony osteolysis. Possibilities of acute abscess, resolving hematoma, or aggressive soft tissue mass lesion were suggested. An incision biopsy showed morphological features of epithelioid osteosarcoma, which was confirmed on immunohistochemistry. A detailed history revealed that our patient was diagnosed as having osteosarcoma of his right leg 3 years previously. Based on history, radiology, morphology, and immunohistochemistry, a final diagnosis of extraskeletal (soft tissue) epithelioid osteogenic sarcoma of the left hand occurring as a metachronous tumor 3 years after diagnosis of primary osteosarcoma in the right leg was given.

Conclusion

This is probably the first reported case of extraskeletal (soft tissue) epithelioid osteosarcoma occurring as a metachronous tumor 3 years after diagnosis of primary osteosarcoma in the right leg. The prognosis of metachronous skeletal osteosarcoma is poor as compared to that of relapse limited to lungs. In late metachronous osteosarcoma, combined-modality therapy comprising surgery and aggressive chemotherapy may affect long-term survival. Lifelong follow-up of surviving patients with osteosarcoma is necessary and if metachronous osteosarcoma is discovered, it should be treated with curative intent.

Electronic supplementary material

The online version of this article (10.1186/s13256-019-2070-3) contains supplementary material, which is available to authorized users.

Epithelioid Osteosarcoma of the Maxilla

Epithelioid osteosarcoma is an uncommon variant; only 4 cases have been reported in the jaw area, 2 of which were in the maxilla. A 22-year-old woman, in the eighth month of pregnancy, presented to the oral surgery clinic with a mass in the right maxilla that had rapidly expanded over the past 3 months. Computed tomography scans showed an ill-defined sclerotic destructive lesion that formed bone matrix in its soft tissue extension. Microscopic examination of the lesion revealed malignant epithelioid cells with osteoid deposits. The tumor cells were shown to have pale cytoplasm, vesicular nuclei, and prominent nucleoli and to undergo frequent mitosis. In addition, the tumor was positive for epithelial membrane antigen and vimentin and negative for AE1/AE3, Melan-A, CD30, synaptophysin, NSE, CD45, CD99, desmin, and myogenin. The final diagnosis was epithelioid osteosarcoma, which is a rare aggressive variant of osteosarcoma. Few cases of epithelioid osteosarcoma have been reported in the literature, and more studies are required to determine the clinical behavior of this tumor.

Diversity of Histologic Patterns and Expression of Cytoskeletal Proteins in Canine Skeletal Osteosarcoma

Osteosarcoma (OS), the most common bone tumor, includes OS of the head (OSH) and appendicular OS (OSA). In dogs, it is classified into 6 histologic subtypes: osteoblastic, chondroblastic, fibroblastic, telangiectatic, giant cell, and poorly differentiated. This study investigated the significance of the histologic classification relevant to clinical outcome and the histologic and immunohistochemical relationships between pleomorphism and expression of cytoskeletal proteins in 60 cases each of OSH and OSA. Most neoplasms exhibited histologic diversity, and 64% of OS contained multiple subtypes. In addition to the above 6 subtypes, myxoid, round cell, and epithelioid subtypes were observed. Although the epithelioid subtypes were observed in only OSH, no significant difference in the frequency of other subtypes was observed. Also, no significant relevance was observed between the clinical outcome and histologic subtypes. Cytokeratin (CK) was expressed in both epithelioid and sarcomatoid tumor cells in various subtypes, and all CK-positive tumor cells also expressed vimentin. Vimentin and α-smooth muscle actin (SMA) were expressed in all subtypes. A few SMA-positive spindle-shaped tumor cells exhibited desmin expression. Glial fibrillary acidic protein-positive tumor cells were observed in many subtypes, and some of these cells showed neurofilament expression. Although OSH exhibited significantly stronger immunoreactivity for SMA than OSA, no significant difference in other cytoskeletal proteins was observed. Some tumor cells had cytoskeletal protein expression compatible with the corresponding histologic subtypes, such as CK in the epithelioid subtype and SMA in the fibroblastic subtype. Thus, canine skeletal OS is composed of pleomorphic and heterogenous tumor cells as is reflected in the diversity of histologic patterns and expression of cytoskeletal proteins.

[Telangiectatic osteosarcoma secondary to a liposclerosing myxofibrous tumor: a case report]

Malignant transformation of a fibrous dysplasia into an osteosarcoma is very rare. We report the case of an 84-year-old man with telangiectatic osteosarcoma of the upper femur arising in a previous fibrous dysplasia also known as liposclerosing myxofibrous tumor. The tumor was expressing the epithelial membrane antigen. This is the first described case of a malignant transformation into an osteosarcoma arising in a liposclerosing myxofibrous tumor. We discuss the main differential diagnosis with a review.

Osteosarcoma of the femur mimicking Ewing sarcoma/primitive neuroectodermal tumour on biopsy and metastatic carcinoma on resection

Osteosarcoma (OS) is known to have several morphological appearances, small cell osteosarcoma and epithelioid osteosarcoma being two well recognized patterns. The former can be mistaken for a Ewing sarcoma/primitive neuroectodermal tumour (ES/PNET), whereas the latter mimics metastatic carcinoma. Herein we present an osteosarcoma in a 17-year-old girl that was diagnosed as an ES/PNET on biopsy; however, the resected specimen revealed a very unusual morphology mimicking a metastatic carcinoma with a sex cord stromal tumour-like pattern.

Chondroblastic osteosarcoma of the temporal region: a diagnostic dilemma

Chondroblastic osteosarcoma (OS) accounts for about 25% of all cases of OS. It can pose diagnostic difficulty on cytology, as the tumor cells may resemble the carcinomatous cells. We present a case of a 35-year-old female patient who presented with a firm swelling in the left temporal region. On fine-needle aspiration, the smears revealed abundant cellularity with tumor cells showing significant nuclear pleomorphism and multinucleation. The tumor cells had abundant foamy to vacuolated cytoplasm, thereby indicating sebaceous differentiation and it was cytologically interpreted as sebaceous carcinoma. However, on subsequent histopathology, similar tumor cells were seen lying down abundant amount of osteoid material along with foci of chondroid differentiation and was diagnosed as chondroblastic OS. Pitfalls in the cytodiagnosis of this case along with differential diagnosis on cytology are discussed.

Progression of aggressive metastatic carcinosarcoma after treatment of epithelioid osteosarcoma

Osteosarcoma is the most common primary malignant osseous neoplasm, constituting approximately 35% of skeletal malignancies. The different subtypes of osteosarcoma are differentiated based on clinical, histologic, and radiographic data, as well as the variable amount of osteoid produced by malignant cells. The epithelioid osteosarcoma subtype accounts for only 5.7% of all osteosarcomas and portends an extremely poor prognosis. The 5-year survival rate for patients with epithelioid osteosarcoma treated with surgery (with or without chemotherapy) is 13.5%. This is in direct contrast to the >70% ten-year survival rate of conventional osteosarcoma treated with surgery and chemotherapy. This article presents a fatal case of epithelioid osteosarcoma in an 11-year-old girl with right knee pain of 6 months' duration. Biopsy demonstrated morphologic findings consistent with high-grade osteosarcoma with epithelioid features. The epithelioid component was positive for vimentin and CD99; however, fluorescent in situ hybridization for the (11;22) translocation was negative. In this case, the epithelioid cells failed to respond to conventional or subsequent experimental chemotherapy for osteosarcoma and eventual metastasized to the lymph nodes and lungs despite multiple ablative surgeries. This case report supports the concept of carcinosarcoma with malignant cells lines arising from 2 different cellular lineages or a common cellular precursor. The epithelial component was more aggressive than the cells of mesenchymal origin, highlighting the need for continued research and a more favorable outcome for this rare subset of osteosarcoma.

Epithelioid osteosarcoma of the jaw

Epithelioid osteosarcoma (OS) is a rare sub-type of OS with an aggressive behavior. An epithelioid OS was diagnosed in an 8-year-old female with painful swelling of the left jaw. After two courses of chemotherapy (cisplatin/methotrexate/doxorubicin), the patient presented a progressive disease. After hemimandibulectomy, 13 courses of post-operative chemotherapy (cisplatin/methotrexate/doxorubicin/ifosfamide) were performed. Histological and ultra-structural examination showed a high grade neoplasm consisting of sheets of epithelioid cells with focal osteoid formation. The patient is alive and in complete remission 42 months from diagnosis.

Squamous differentiation and cytokeratin expression in an osteosarcoma: a case report and review of the literature

Cytokeratin expression has been documented in a variety of sarcomas including synovial sarcomas, epithelioid sarcomas, Ewing's sarcomas and, rarely, osteosarcomas. In osteosarcomas immunohistochemically shown to expression cytokeratins, a component of epithelioid cells is generally present. These epithelioid cytokeratin positive cells raise the possibility of metastatic disease with prognostic and therapeutic implications differing from primary osteosarcoma. The cytokeratin-expressing cells of the cases reported in the literature have not shown definitive squamous differentiation with keratin pearl formation. We report a case of osteosarcoma in which islands of malignant squamous cells were present showing keratin pearl formation and expression of cytokeratins.

Epithelioid osteosarcoma of the mandible: a rare case with unusual immunoprofile

A 42-year-old woman presented a large, nontender, quickly progressive mass in the left mandible. Radiograph showed extensive destruction of the angle, posterior body, and ramus of the left side of the mandible. The patient was surgically treated by hemimandibulectomy. Microscopically, the tumor was composed of large epithelioid cells, many of them showing polarized nuclei, and evident eosinophilic cytoplasm. The predominant pattern was trabecular, and rosette-like structures were also observed. Typical osteoid-containing cells surrounded by malignant cells were found in a few areas. Immunohistochemistry for a large panel of antibodies showed positivity for osteocalcin, osteonectin, osteopontin, VS38c, and S-100. CD34 saliented the hemangiopericytoma-like distribution of the blood vessels. Collagen I was focally positive for the extracellular matrix and malignant osteoid. All other markers were negative, including vimentin and cytokeratins. To the best of our knowledge, this is the first case of epithelioid osteosarcoma affecting the mandible and the second case affecting the jaws that has been reported in the literature.

Epithelioid and Epithelial Neoplasms of Bone

Context.—Epithelioid and epithelial neoplasms seen in bone are rare and include epithelioid variants of vascular lesions, osteoblastoma, osteosarcoma, chordoma, and chondroblastoma as well as adamantinoma and metastatic carcinoma.

Objective.—To provide an overview of tumors with epithelioid histology and address the clinical context and diagnostic issues.

Data Sources.—Pertinent literature is reviewed with emphasis on recent and controversial issues.

Conclusions.—The differential diagnosis in epithelioid/ epithelial lesions of bone is limited. The primary consideration in many cases is distinguishing primary from metastatic lesions.

Epithelioid osteosarcoma presenting as a rapidly expanding maxillary mass

BACKGROUND

Osteosarcomas of the jaws account for less than 10% of reported neoplasms of this type. Patients with osteosarcoma in this region tend to be in the late-third to mid-fourth decades of life. The osteoblastic, chondroblastic, and fibroblastic variants constitute the majority of lesions.

METHODS

A mass was observed in the maxilla of a 50-year-old male who presented for a complete odontectomy. Over the ensuing weeks, the mass substantially increased in size, despite multimodality treatment efforts.

RESULTS

Radiographic findings revealed a mixed density mass of the left maxilla. Histologic, immunohistochemical, and electron microscopy examination of the tumor showed a malignant mesenchymal neoplasm consisting of sheets of epithelioid and spindle cells exhibiting focal osteoid formation.

CONCLUSIONS

We report a rare and aggressive case of epithelioid osteosarcoma arising in the maxillofacial complex.

Second primary osteosarcoma with rosette-like structure in a patient with retinoblastoma

A Japanese male patient developed bilateral retinoblastomas at the age of 1 year, but remained continuously disease-free after enucleation of the left eye and radiation therapy to the right eye. He noticed a painless hard mass around the right temporal bone when he was 25 years old. Biopsy specimen showed a small multi-nodular proliferation of tumor cells with prominent rosette-like structures. Eosinophilic material with focal mineralization was seen in the center of the rosettes. Immunostaining of the tumor cells showed positive reactions for epithelial membrane antigens CD 56 and CD 99. The patient was treated with systemic chemotherapy, and the tumor partially diminished. It is well known that a few osteosarcomas show a rosette-like appearance with production of osteoid in the center, but this is the first case of second primary osteosarcoma with prominent rosette-like features.

Prognostic relevance of rosette-like features in osteosarcoma

AIMS

To clarify the prognostic relevance of rosette-like features and other clinicopathological and immunohistochemical variables in patients with osteosarcoma.

METHODS

Clinicopathological and immunohistochemical variables were analysed in 131 patients with non-metastatic high grade conventional osteosarcoma, with particular attention to the prognostic impact of rosette-like features.

RESULTS

Rosette-like features were present in 18 (14%) cases. Rosette-like features were significantly associated with the osteoblastic subtype, numerous osteoclast-like giant cells, moderate pleomorphism, frequent haemangiopericytoma-like vascular patterns, epithelioid cytological features, positive immunoreactivity for epithelial membrane antigen and CD56, and negative staining for cytokeratin. In a multivariate analysis, rosette-like features (relative risk (RR), 3.8), a poor chemotherapy effect (RR, 2.9), and a tumour size of 10 cm or more (RR, 2.8) were identified as unfavourable prognostic factors.

CONCLUSIONS

Rosette-like features can easily be identified from routine histological slides and the relative risk in patients with non-metastatic, conventional osteosarcoma is as high as other well known prognostic factors, including large size and poor chemotherapy effect.

Osteosarcoma with cytokeratin expression: a clinicopathological study of six cases with an emphasis on differential diagnosis from metastatic cancer

AIMS

To clarify the clinicopathological profile of osteosarcomas showing an intensely positive immunoreaction for cytokeratin.

METHODS

Clinicopathological and immunohistochemical features were analysed in 131 patients with non-metastatic, conventional osteosarcoma, treated in Akita University and National Cancer Centre in Tokyo between 1972 and 1999.

RESULTS

Six patients (4.5%; mean age, 32 years; four men, two women) had osteosarcomas showing intense cytokeratin expression. Tumours were located on the long bones of the extremities in five patients and the ilium in one. Osteoid formations were found in biopsied specimens in all cases. Three tumours were classified as osteoblastic osteosarcoma, two as fibroblastic, and one as chondroblastic. In three tumours classified as the osteoblastic subtype, epithelioid features were prominent, and four tumours showed pronounced cellular pleomorphism. In contrast to the expression of cytokeratin, epithelial membrane antigen was negative in all cases. Surgery with a wide excisional margin was performed in six patients. Preoperative and postoperative chemotherapy was given to five of the six patients, but the effects of these agents were negligible. Three of the six patients developed lung metastases, whereas the other three patients have remained well with no evidence of local recurrence or distant metastasis.

CONCLUSIONS

Osteosarcoma with intense immunoreaction for cytokeratin was rare. The clinicopathological features were similar to those of patients with conventional osteosarcoma, except for a higher age, chemotherapy resistance, histological epithelioid features, and pleomorphism. This study indicates that osteoid formation and negative expression of epithelial membrane antigen are key features in the differentiation from metastatic carcinoma.

Rosette formation within a proliferative nodule of an atypical combined melanocytic nevus in an adult

Rosette formation is a feature that has not been described as occurring in melanocytic neoplasms. We present such a unique case. A 59-year-old man presented with an asymptomatic, soft, hairy 3.0 x 2.0-cm pigmented lesion that had been present for many years in the right external ear, extending from the conchal bowl onto the antitragus area. Examination of histologic sections showed a proliferation of nonatypical and heavily pigmented melanocytes in the superficial dermis and around deep adnexal structures, characteristic of a congenital nevus. In other areas, pigmented spindled and dendritic cells infiltrated thickened collagen bundles in a pattern of a blue nevus. A nodular proliferation of epithelioid melanocytes was seen within the deep dermis and subcutaneous tissue. The periphery of the nodule merged with the surrounding nevus cells. Neoplastic cells with nuclear atypia, melanin pigment, pseudonuclear inclusions, and balloon cell change were present. In addition, there was rosette formation by the tumor cells, with a central aggregate of coarse cell processes. Neuroid cords were also noted. No prominent mitotic figures, necrosis, or significant inflammatory infiltrate were noted. The neoplastic cells were positive for S-100 protein, Mart-1, tyrosinase, neuron-specific enolase, and vimentin. HMB-45 and Ki-67 (MIB-1) labeled only rare neoplastic cells within the proliferative nodule. The tumor cells were negative for synaptophysin, protein gene product 9.5, CD57, epithelial membrane antigen, CD31, and CD34. The central cell processes of the rosettes were negative for trichome, type IV collagen, neurofilament protein, glial fibrillary acidic protein, and tyrosine hydroxylase. We also retrospectively examined 78 congenital nevi of 65 pediatric patients at our institution. Rosette formation was not seen in any of these cases.