Dados do Trabalho

Título

Alveolar rhabdomyosarcoma in an adult patient. A case report.

Descrição sucinta do(s) objetivo(s)

Present a very uncommon case in adults. Show the high aggressiveness of these types of musculoskeletal tumors.

História clínica

A 41-year-old woman presented with pain and induration in the perineal region for 3 months, without gynecological or urinary symptoms. Discomfort when evacuating was frequent. No history of trauma or pelvic floor surgery. The patient had no comorbidities. An ultrasound, magnetic resonance imaging and 18F-FDG positron emission tomography were performed, showing an hypermetabolic heterogeneous mass, with polylobulated edges, superficially located with extension to deep tissues. It presented marked enhancement after the administration of intravenous contrast, lymph node metastases, peritoneal implants, at the pancreatic level and bone involvement.
The patient underwent to a percutaneous biopsy, which revealed small-round-blue-cell-tumors with myogenin and desmin positive linked to alveolar type Rhabdomyosarcoma.

Discussão e diagnóstico

Rhabdomyosarcomas are tumors originating from immature mesenchymal cells with differentiation into striated muscle and do not necessarily originate in sites where there is this type of muscle. They are typically of pediatric age (70% <10 years), being rare in adults (<3% of soft tissue sarcomas)
The most common primary sites are head and neck (e.g. parameningeal, orbit, pharyngeal, etc.) ; the genitourinary system; the extremities. Less common are the trunk, chest wall, abdomen, and perineum/anus region.
The diagnosis is essentially histopathological, particularly by immunohistochemistry. The role of the image is to characterize the lesion, its aggressiveness and distant metastasis by nuclear medicine.

Conclusões

In conclussion, soft tissue tumors represent a diagnostic challenge for the radiologist due to the variety of differential diagnoses involved. The different diagnostic methods available aids in characterizing these tumors, assessing involvement of adjacent organs, and enabling access for proper diagnostic sampling, ensuring timely diagnosis and treatment.

Palavras Chave

Rabdomiossarcoma; PET/CT; musculoesquelético

Arquivos

Área

Sistema Musculoesquelético