The gamut of primary retroperitoneal masses: multimodality evaluation with pathologic correlation

Area of Science:

• Radiology
• Oncology
• Pathology

Background:

• The retroperitoneum harbors primary and metastatic tumors that often remain asymptomatic until advanced stages.
• Retroperitoneal neoplasms exhibit diverse histologies, ranging from benign to aggressive, and can be solid or cystic.
• Solid primary retroperitoneal neoplasms are rare, originating from mesodermal, neurogenic, or extragonadal germ cell tissues.

Purpose of the Study:

• To illustrate the spectrum of multidetector computed tomography (MDCT) imaging findings in primary retroperitoneal masses.
• To emphasize cross-sectional imaging features for accurate tumor characterization and staging.
• To aid in distinguishing benign from malignant masses to optimize patient management.

Main Methods:

• Review of multidetector computed tomography (MDCT) imaging findings in common and uncommon primary retroperitoneal masses.
• Analysis of imaging features such as fat, calcification, necrosis, vascularity, and neural foraminal widening for tumor differentiation.
• Correlation of imaging characteristics with tumor morphology and biologic activity (positron emission tomography - PET).

Main Results:

• Retroperitoneal neoplasms can grow large before causing nonspecific symptoms.
• Imaging features on MDCT are pivotal for detection, staging, and pre-operative planning.
• Specific imaging characteristics aid in differentiating tumor types and guiding therapeutic decisions.

Conclusions:

• Meticulous cross-sectional imaging is essential for characterizing retroperitoneal masses and triaging patients.
• Complete surgical excision is critical for long-term survival in malignant cases.
• Biopsy decisions should be made in consultation with surgical oncology to preserve curative surgical options.