Expandable distal femoral megaprostheses
Over the last 20 years, expandable prostheses have made a significant impact on the reconstruction methods we routinely use in children with bone tumors.[1-4] Although these implants are expensive and associated with a high complication rate [5-9], even in experienced hands, they are considered the main reconstructive option for children in a certain age group and for selected bone segments.
EMSOS study on expandable distal femoral megaprostheses.pdf190.02 KB
Desmoplastic Fibroma of bone
Fibroma of bone is a rare, locally aggressive bone tumor. Once it was called the osseous counterpart of extra-abdominal desmoid tumor, because of the histological aspects. In 2013, the WHO described the microscopic appearance of desmoplastic fibroma as being composed of slender, spindle to stellate cells with minimal cytological atypia and abundant collagenous matrix.
Desmoplastic Fibroma of bone.pdf135.88 KB
Desmoplastic Fibroma EMSOS study datasheet.xls48.00 KB
EMSOS Extra-abdominal Fibromatosis Multicenter Study
Desmoid-type fibromatosis is an intermediate soft tissue tumour (WHO) with clonal fibroblastic proliferation originating in the deep soft tissues. It is characterised by local infiltration without metastatic potential. In the past decades resectable masses have been mainly treated surgically with a high incidence of local recurrence in up to one third of the patients independently from resection margins. Local recurrence negative prognostic factors after surgery have been identified in younger age, female gender, distal limb location and recurrent disease.
Alternative management including radioterapy or medical treatment with NSAIDS, hormone therapy, chemotherapy and tyrosine kinase inhibitors led to high recurrence rate as well.
As a consequence in recent years the wait and see approach, with strict and close clinical and instrumental monitoring of the involved site has gained popularity as first line management for silent masses not involving neurovascular bundles.
Clear cell chondrosarcoma
Clear cell chondrosarcoma is a rare variant of chondrosarcoma, behaving as a low grade malignant bone tumor and characterized by a proliferation of tumor cells with clear cytoplasm.
Clear cell chondrosarcomas account for around 2% of all chondrosarcomas. They have been described in most bones of the body but usually affect the proximal epiphysis of the humerus or femur.
Doz. Dimosthenis Andreou, Münster, Germany
Mazabraud Syndrome is a very rare combination of fibrous dysplasia (FD) and intramusculary myxomas. Both entities are caused by activating GNAS-mutations and while FD is often diagnosed at a younger age, myxomas tend to arise later, often in the fourth or fifth decade of life, and are localized adjacent to FD lesions in the majority of the patients. The myxomas can lead to mechanical problems and symptoms of pain. Excision of the myxomas has been proposed, although outcome of surgical interventions and whether there are predictive factors for recurrence of the myxomas remains eluded.
EMSOS Study "Angiosarcom"
Angiosarcoma is the malignant end of the spectrum of vascular tumors, spanning diagnosis including hemangiomas, hemangioendothelioma, well-differentiated and poorly-differentiated angiosarcoma.
Angiosarcoma of bone is rare, accounting for <1% of all primary bone sarcomas and it is associated with a poor prognosis. Although any age can be affected, the incidence is highest between 50 and 70 years of age.
Angiosarcoma of bone may present as unifocal or multifocal disease. The most common locations of unifocal tumor are the long and short tubular bones, followed by the pelvis, and trunk.
Histologically, angiosarcomas of bone are composed of anastomosing vascular channels lined by atypical endothelial cells with enlarged nuclei, prominent nucleoli, and increased mitoses. Inflammatory cells, mostly eosinophils, may be present.
Given the rarity of angiosarcoma of bone, the literature is limited regarding treatment and outcome of patients with this tumor.
The role of chemotherapy and prognostic factors for these patients remain unclear.
Under the auspices of the EMSOS, a retrospective study has been launched with the aim of improving our knowledge on the natural history of the tumor and on prognostic and predictive factors of survival.
Stefano Ferrari MD
SSD Chemioterapia dei Tumori Muscoloscheletrici
Istituto Ortopedico Rizzoli – WWW.ior.it
Via Pupilli 1, 40136 Bologna. Italy
DGOOC / EMSOS study "Clear cell sarcoma"
Osteosarcoma after retinoblastoma
European Relapsed Osteosarcoma Registry "EURELOS"