mesenchymal hamartomas of the chest wall

Chondromesenchymal

hamartomas in a 24-year-old male mimicking a posterior mediastinal tumor and a 5-month-old boy with postoperative disseminated intravascular coagulation: two case reports. Radiological appearance of chondromesenchymal hamartoma of the chest wall in a 24-year-old adult. a, b DR suggested a left posterosuperior mediastinal mass and bronchitic changes. c CT revealed a benign expansile lesion in the posterior part of the left fifth rib with interior punctate calcifications. d-f MRI revealed a well-circumscribed expansile heterogeneous soft mass closely adjoining the fifth vertebral body in the left posterior mediastinum. DR, digital radiography; CT, computed tomography; DR, digital radiography; MRI, magnetic resonance imaging

diagnosticpathology.biomedcentral.com • CC-by-4.0

Chondromesenchymal

hamartomas in a 24-year-old male mimicking a posterior mediastinal tumor and a 5-month-old boy with postoperative disseminated intravascular coagulation: two case reports. Imaging findings of chondromesenchymal hamartoma of the chest wall in a 5-month-old infant. a DR revealed a soft tissue mass in the left middle lung field, accompanied by collapse of the adjacent thoracic cage. b DR revealed postoperative loss of parts of the left fifth and sixth ribs. c, d CT revealed a benign solid-cystic lesion with multiple speckled and cord-like high-density shadows, arising from the axillary segment of the left fifth and sixth ribs; the corresponding cortical and medullary cavities of the ribs were involved. DR, digital radiography; CT, computed tomography

diagnosticpathology.biomedcentral.com • CC-by-4.0

Radiopaedia • CC-by-nc-sa 3.0 • de

A mesenchymal hamartoma of the chest wall is a very rare benign chest wall tumor. It is sometimes classified as a non-neoplastic developmental anomaly rather than a tumor.

Epidemiology

They typically present in neonates or infants .

Clinical presentation

Many present with a chest wall mass . Some may present with respiratory distress or a chest wall deformity .

Pathology

Macroscopically the tumors are generally well delineated, lobulated, and tan to reddish in color .

Microscopically, they tend to show showed alternating areas of cartilaginous islands and primitive appearing mesenchymal proliferation. There may be also areas of bone formation and blood-filled cystic spaces (secondary aneurysmal bone cyst formation).

Location

Many lesions arise from the ribs. Some can have multifocal disease.

Radiographic features

General

Radiologically they are well-circumscribed masses with solid and cystic components. They may have multiple fluid-fluid levels, in association with single or multiple rib destruction or change.

Plain radiograph

Plain radiographs may show a well-defined, partly calcified mass involving one or more ribs.

MRI

MRI usually shows heterogeneous signal intensities of the mass on both T1- and T2-weighted images. Hemorrhagic cavities (secondary aneurysmal bone cyst regions) are readily detectable in MRI .

Treatment and prognosis

Rapid growth may occur but usually is self-limited. While the general rule is that they are they are non-neoplastic, occasional cases of malignant transformation have been reported . En bloc resection is curative, but the large residual chest wall defect can frequently result in scoliosis .