SPECT/CT imaging of retroperitoneal extraskeletal osteosarcoma

Area of Science:

• Oncology
• Radiology
• Pathology

Background:

• Extraskeletal osteosarcoma is a rare malignant bone tumor arising outside the skeleton.
• Retroperitoneal location of this tumor presents unique diagnostic and surgical challenges.

Observation:

• A 52-year-old male presented with unresectable retroperitoneal extraskeletal osteosarcoma.
• SPECT/CT imaging showed the tumor adjacent to the right upper ureter with significant calcifications and Technetium-99m methylene diphosphonate (Tc-MDP) uptake.
• Multiple metastases were identified in the hepatic capsule, renal fascia, and peritoneum.

Findings:

• Second-look surgery four months later confirmed widespread peritoneal metastases.
• Histopathologic examination definitively diagnosed osteosarcoma.

Implications:

• This case highlights the aggressive nature and metastatic potential of retroperitoneal extraskeletal osteosarcoma.
• Advanced imaging like SPECT/CT is crucial for staging and assessing treatment response in such rare tumors.
• Early detection and comprehensive histopathological analysis are vital for accurate diagnosis and management planning.