Dados do Trabalho


Título

Main differences between pediatric mediastinal masses: diagnostic tips

Descrição sucinta do(s) objetivo(s)

Highlight the main characteristics that help in the differential diagnosis of mediastinal masses in children.

Descrição da(s) doença(s), método(s) e/ou técnica(s)

Mediastinal masses in children have a varied embryological origin and may present similar symptoms. A rigorous assessment of the location of the tumor (anterior, middle or posterior mediastinum), its radiological characteristics and the patient's age are essential for an adequate diagnosis.

Discussão

Lymphoma
• Malignant neoplasms arising from cells of the immune system or their precursors.
• More common in the anterior mediastinum. Peak incidence in the second decade of life.
• Hodgkin's lymphoma: lobulated masses due to multiple homogeneous, non-calcified, lymph nodes enlargement, without necrosis (except if tumor lysis).
• Non-Hodgkin's Lymphoma: thymic infiltration with lobulations and homogeneous enhancement, airway compression and pulmonary involvement (nodules, cavitations, consolidations and pleural effusion).

Tuberculosis
• Infectious disease caused by Mycobacterium tuberculosis.
• More common in the middle mediastinum. Peak incidence between age 1 to 5.
• Lymphadenopathy (paratracheal and perihilar) is often the dominant feature of mediastinum enlargement, with foci of necrosis, related to parenchymal consolidation, often lower zone, and pleural effusion.

Germ cell tumors
• Tumors derived from primordial germ cells and are subdivided into teratomas, seminomas and nonseminomatous.
• More common in the anterior mediastinum, but it can occur in the posterior mediastinum. Peak incidence between age 15 to 35.
• Predominantly heterogeneous mass, adjacent to the thymus, which may present fatty tissue, cystic images and calcifications - teratoma -, lobulations and bulky mass - seminoma -, and areas of hemorrhage, necrosis and tissue invasion -not seminoma.

Thoracic neuroblastoma
• Malignant tumor of primitive neural crest cells, most commonly the adrenal glands.
• More common in the posterior mediastinum. Peak incidence at 2 years.
• Heterogeneous mass, with foci of necrosis, hemorrhage and calcification (85%), paraspinal in location, with costal involvement (erosions and enlargement of the costal space) and invasion of vertebral foramina.

Conclusões

Mediastinal masses in children are difficult to diagnose, requiring adequate knowledge of the epidemiology, clinical and radiological characteristics of the disease. Radiologists must continually update their knowledge to provide the best possible care for pediatric patients.

Palavras Chave

Mediastinum masses; pediatria;

Arquivos

Área

Pediatria

Instituições

Universidade Federal de São Paulo - São Paulo - Brasil

Autores

LUIS FERNANDO FREITAS, ANA LARA ALMEIDA, FLAVIA GEORGETO FREIRE, RODRIGO RAGAZZINI, TAISA MELO GUARILHA