Mesenchymal hamartoma of the chest wall is a rare tumor with about 53 reported cases in the English literature. We reviewed six chest wall mesenchymal hamartomas in four patients, including two cases with multiple lesions, with specific focus on the radiologic and pathologic correlation. All cases occurred in neonates or infants with ages ranging from seven hours to seven months. They were diagnosed with plain chest radiographs (n=6), ultrasonography (n=2), chest CT scan (n=6), whole body bone scan (n=2) and MRI (n=3). All cases except a small one without cystic change showed the typical features of mesenchymal hamartoma radiographically and pathologically. Radiologically they were well-circumscribed masses with solid and cystic components with multiple fluid-fluid levels in association with single or multiple rib destruction or change. The CT scan showed the typical findings of chest wall hamartoma, and the MR showed heterogeneous signal intensities of the mass on T1- and T2-weighted images. The MR also revealed more concisely a secondary aneurysmal bone cyst formation with multiple fluid-fluid levels on the T2-weighted image. Microscopically, they showed alternating areas of cartilaginous islands and primitive appearing mesenchymal proliferation, which corresponded well with the solid component on the radiologic findings. The areas of bone formation and blood-filled cystic spaces matched the calcified or ossified densities and the cystic components, respectively. A small case without cystic change showed peculiar radiological and pathological findings resembling an osteochondroma. In conclusion, mesenchymal hamartoma of the chest wall in infancy is quite rare and sometimes can be misdiagnosed as malignancy due to the bone-destroying radiographic appearance and the highly cellular and mitotically active microscopic features, unless the radiologists and pathologists are aware of the characteristic clinical, radiological, and pathological findings. Imaging studies can usually make a correct diagnosis with good correlation to the pathologic findings.
Female ; Hamartoma/ultrasonography ; Hamartoma/radiography*e ; Hamartoma/pathology* ; Human ; Infant ; Magnetic Resonance Imaging ; Male ; Mesoderm/ultrasonography ; Mesoderm/radiography ; Mesoderm/pathology ; Radiography, Thoracic ; Thoracic Neoplasms/ultrasonography ; Thoracic Neoplasms/radiography* ; Thoracic Neoplasms/pathology* ; Tomography, X-Ray Computed

Fibrous dysplasia is a skeletal developmental anomaly of the bone-forming mesenchyme that manifests as a defect in osteoblastic differentiation and maturation. It is a nonhereditary disorder of unknown cause. In fibrous dysplasia, the medullary bone is replaced by fibrous tissue, which appears various imaging findings. It is usually an incidental finding, generally not requiring further investigation. However, fibrous dysplasia may be complicated by pathologic fracture, and rarely by malignant degeneration. We present the image findings of a 44-year-old man who had a chondroblastic osteosarcoma arising from polyostotic fibrous dysplasia in the femur. Evidence of cortical destruction on plain radiography and soft tissue mass in the lesion on MR images suggested a tumor of malignant transformation.
Adult ; Chondrocytes ; Femur ; Fibrous Dysplasia, Polyostotic* ; Fractures, Spontaneous ; Humans ; Incidental Findings ; Mesoderm ; Osteoblasts ; Osteosarcoma* ; Radiography

This paper presents an unusual solid mesenchymal hamartoma of the liver (MHL) in adult. A well defined solid mass in the left lobe of the liver was found in a 57-year-old female. Preoperative radiologic examinations demonstrated solid mass with multifocal calcifications abutting the gallbladder. By light microscopy, the lesion was composed of dense fibrous stroma with hyalinization, bile ducts and thick-walled vessels without hepatocytes. The solid and hyalinized mesenchymal component would suggest an unusual degenerative change representing a burnt-out MHL.
Case Report ; Female ; Hamartoma/surgery ; Hamartoma/radiography ; Hamartoma/pathology* ; Human ; Liver Neoplasms/surgery ; Liver Neoplasms/radiography ; Liver Neoplasms/pathology* ; Mesoderm/pathology ; Middle Age ; Tomography, X-Ray Computed

OBJECTIVE: A hepatic mesenchymal hamartoma is an uncommon benign tumor in children and little is known about the spectrum of its radiological features. The purpose of this study is to describe the spectrum of radiological features of a hepatic mesenchymal hamartoma in children. MATERIALS AND METHODS: Thirteen children with a pathologically confirmed hepatic mesenchymal hamartoma (M:F = 7:6; mean age, 3 years 2 months) were included in our study. Ultrasonography (US) was performed in nine patients including color and power Doppler US (n = 7). CT scans were performed in all patients. We evaluated the imaging findings of the hepatic mesenchymal hamartomas and the corresponding pathological features. RESULTS: Each patient had a single tumor (mean diameter: 13 cm [1.8-20 cm]). On CT and/or US, four patients (31%) had a "multiseptated cystic tumor", five patients (38%) had a " mixed solid and cystic tumor", and four patients (31%) had a "solid tumor." The septa of the cystic portion were thin in the multiseptated cystic tumors and irregularly thick in the mixed solid and cystic tumors as seen on US. On a post-contrast CT scan, solid portions or thick septa of the tumors showed heterogeneous enhancement. The amount of hepatocytes was significantly different among the three tumor groups according to the imaging spectrum (p = 0.042). CONCLUSION: A hepatic mesenchymal hamartoma in children can show a wide spectrum of radiological features, from a multiseptated cystic tumor to a mixed solid and cystic tumor, and even a solid tumor.
Child ; Child, Preschool ; Contrast Media/administration & dosage ; Female ; Hamartoma/*diagnosis ; Humans ; Infant ; Liver/*radiography/ultrasonography ; Liver Neoplasms/*diagnosis ; Male ; Mesoderm/*radiography/ultrasonography ; Observer Variation ; Radiographic Image Enhancement/methods ; Retrospective Studies ; Tomography, X-Ray Computed/methods ; Ultrasonography, Doppler, Color/methods