Ewing sarcoma is most commonly a bone tumour which has usually extended into the soft tissues at the time of diagnosis. Exceptionally, this tumour can have an extraskeletal origin. Clinical or imaging findings are non-specific and diagnosis is based on histology. We report a case of an extraskeletal Ewing sarcoma developed in the soft tissues of the abdominal wall in a 35-year-old woman who pre...

Extraskeletal osteosarcoma is a very rare tumor in humans and animals including rats. This paper describes a case of extraskeletal osteosarcoma observed in the glandular stomach of an aged female Fischer 344 rat. Grossly, a whitish solid mass was observed at the greater curvature of the glandular stomach. Histologically, the tumor consisted of both atypical polygonal and pleomorphic spindle-sha...

Osteochondromas are common benign tumors of cartilage and bone. They are usually found as contiguous bone with a cartilage cap at the end of the growth plate of long bones. Similar to structure are extraskeletal osteochondromas. However, unlike typical osteochondromas, extraskeletal osteochondromas are noncontinuous with bone. To our knowledge, all reported extraskeletal osteochondromas have be...

A 52 year old man developed an extraskeletal mesenchymal chondrosarcoma (ESMC) arising from the pleura. Clinically, the tumour mimicked a mesothelioma. Fine needle biopsy was consistent with the diagnosis of sarcomatoid mesothelioma. Histological examination of multiple tumour samples, supported by immunohistochemical characterization, made it possible to correctly diagnose extraskeletal mesenc...

Extraskeletal osteosarcoma is a rare soft tissue sarcoma and is in many ways distinct from skeletal osteosarcoma, including demographics, imaging feature, prognosis and management. We present a case of extraskeletal osteosarcoma arising from the retroperitoneum with dense ossification proved to be osteosarcoma by surgical resection. We describe the computed tomography (CT) and magnetic resonanc...

Extraskeletal mesenchymal chondrosarcoma is extremely rare and, in combination with psoriasis, it has never been described before. We report a case of wide resection of an extraskeletal chondrosarcoma of the thigh and reconstruction with a femoral megaprosthesis in a patient with psoriasis vulgaris. Special emphasis has been laid to postoperative wound healing in psoriatic skin which did not sh...

Primary extraskeletal myxoid chondrosarcoma of the pulmonary arteries is a very rare entity. Multimodality imaging reports on this entity are few. Myxoid chondrosarcoma is characterized by chondroid and neurogenic differentiation in extraskeletal locations. These tumours represent fewer than 2.5% of all soft-tissue sarcomas, and are most commonly found in the lower extremities, limb girdles, di...

Primary intradural extraskeletal Ewing sarcoma is a very rare form of malignant neoplasm. Only few cases have been reported on the literature. Here, we report a case of a 14-year-old boy who had a chief complaint of pain and tingling in the right lower limb. The patient initially seemed to have a giant nerve sheath tumor but was eventually diagnosed with intradural extraskeletal Ewing sarcoma a...

Extraskeletal osteochondroma in the nape of the neck is rare and its pathological diagnosis is based on radiological and histopathological examination. It is vital that such a diagnosis be considered when a discrete, ossified mass is localised in soft tissues, even at atypical sites. Differential diagnoses include myositis ossificans, a lipomatous lesion, a pseudomalignant osseous tumour, an os...

Extraskeletal osteosarcoma is a rare malignant soft tissue tumor. Here we present a case of a primary extraskeletal osteosarcoma arising from omentum majus in a 40-year-old Chinese woman. Ultrasonography of the pelvic cavity showed a large soft tissue mass with marked calcification. Complete surgical resection of the primary tumor was performed and the histopathological diagnosis was extraskele...