Pelvic Ewing Sarcoma: The Great Mimicker.

Ewing sarcoma is the most common malignant bone tumor of the pelvis in children and young adults. Even with aggressive treatment, its survival rate is amongst the poorest. Classical presentation may not be the rule. It may simulate clinically, imagiologically and histopathologically other nonmalignant entities. Therefore, its suspicion should not be overlooked. We report two cases of pelvic Ewing sarcoma: the first mimicking eosinophilic granuloma, and the second mimicking osteomyelitis. In the latter, we also report an atypical finding of its natural history: an initial response to antibiotic and anti-inflammatory treatment. In both cases, we highlight the possibility of an inconclusive percutaneous bone biopsy and the importance of immunochemistry and cytogenetics for the definitive diagnosis.

Pelvic Ewing Sarcoma: The Great Mimicker / Sarcoma de Ewing pélvico: o grande imitador

Abstract Ewing sarcoma is the most common malignant bone tumor of the pelvis in children and young adults. Even with aggressive treatment, its survival rate is amongst the poorest. Classical presentation may not be the rule. It may simulate clinically, imagiologically and histopathologically other nonmalignant entities. Therefore, its suspicion should not be overlooked. We report two cases of pelvic Ewing sarcoma: the first mimicking eosinophilic granuloma, and the second mimicking osteomyelitis. In the latter, we also report an atypical finding of its natural history: an initial response to antibiotic and anti-inflammatory treatment. In both cases, we highlight the possibility of an inconclusive percutaneous bone biopsy and the importance of immunochemistry and cytogenetics for the definitive diagnosis.

Resumo O sarcoma de Ewing é o tumor ósseo maligno da pelve mais comum em crianças e adultos jovens. Mesmo com tratamento agressivo, sua taxa de sobrevivência está entre as piores. A apresentação clássica pode não ser a regra. Ele pode simular clinicamente, imaginologicamente e histopatologicamente outras entidades não malignas. Portanto, sua suspeita não deve ser negligenciada. Relatamos dois casos de sarcoma pélvico: o primeiro imitando granuloma eosinofílico e o segundo imitando osteomielite. Neste último, também relatamos um achado atípico de sua história natural: uma resposta inicial ao antibiótico e ao tratamento anti-inflamatório. Em ambos os casos, destacamos a possibilidade de uma biópsia óssea percutânea inconclusiva e a importância da imunoquímica e da citogenética para o diagnóstico definitivo.

The Lateral Approach in the Surgical Treatment of a Complex Dorsal Metacarpophalangeal Joint Dislocation of the Index Finger.

Complex dorsal metacarpophalangeal (MCP) joint dislocations as a result of hyperextension injuries are uncommon in the pediatric population and irreducible to closed maneuvers. Treatment of these complex lesions is invariably surgical, and dorsal or volar approaches are traditionally used. The authors describe a case of a 16-year-old male who suffered a fall onto his outstretched right hand in a soccer game. The patient presented to the ER with pain and deformity of the index finger MCP joint. Radiographs confirmed a complex MCP dislocation with a small osteochondral fragment. A lateral surgical approach was made, and interposition of the volar plate and an osteochondral fragment blocking the reduction were found. This versatile approach allowed access to volar and dorsal structures, minimizing the risk of surgical scarring and mobility arch limitation. To our knowledge, there are no reported cases regarding a lateral surgical approach.