[CT and MRI imaging features of peripheral primitive neuroectodermal tumors]

Area of Science:

• Radiology
• Oncology
• Pathology

Background:

• Peripheral primitive neuroectodermal tumors (pPNETs) are rare, malignant neoplasms.
• These tumors typically affect children and adolescents.
• Understanding their imaging characteristics is crucial for diagnosis.

Purpose of the Study:

• To investigate the CT and MRI features of peripheral primitive neuroectodermal tumors (pPNETs).
• To evaluate the diagnostic value of imaging findings for pPNETs.

Main Methods:

• Retrospective analysis of clinicopathological data from 9 surgically treated patients with pPNETs.
• Review of CT (4/9) and MRI (6/9) scans, including plain and dynamic contrast-enhanced imaging.
• Correlation of imaging findings with histopathological results.

Main Results:

• Tumors ranged from 7.4-18.3 cm, often presenting as large, ill-defined masses in skeletal muscle, pelvic, or thoracic cavities.
• Imaging showed homogeneous or inhomogeneous density on CT, with iso-density to adjacent muscles.
• MRI revealed variable signal intensities and heterogeneous, delayed enhancement, frequently with necrosis and cystic formation, especially in chest/pelvic tumors.

Conclusions:

• pPNETs are malignant tumors characterized by small, undifferentiated neuroectodermal cells.
• Typical imaging findings include large, ill-defined masses with heterogeneous enhancement and necrosis.
• Imaging features, particularly enhancement patterns and necrosis, are valuable for diagnosing pPNETs.