Extremity bone tumors: evaluation by P-31 MR spectroscopy

Area of Science:

• Biophysics
• Oncology
• Medical Imaging

Background:

• Distinguishing benign from malignant bone lesions is crucial for effective treatment.
• Phosphorus-31 magnetic resonance (P-31 MR) spectroscopy offers insights into cellular metabolism.
• Previous P-31 MR studies have primarily focused on animal models or implanted human tumors.

Observation:

• High-resolution P-31 MR spectra were acquired from four patients with distal extremity bone tumors.
• One patient with Ewing sarcoma was evaluated post-treatment, while three others with active chondrosarcoma, malignant fibrous histiocytoma, and chondroblastoma were studied.
• Bone scintigraphy confirmed active tumor growth and increased metabolism in three of the patients.

Findings:

• Active bone tumors exhibited high adenosine triphosphate (ATP) content, comparable to animal tumor models.
• Elevated inorganic phosphate and reduced phosphocreatine resonances were observed in active tumors.
• Phosphodiester and phosphomonoester peaks indicated the presence of these metabolites, with slight changes noted post-chemotherapy in one case.
• Healthy bone P-31 MR spectra lacked well-resolved signals, contrasting with tumor spectra.

Implications:

• P-31 MR spectroscopy can differentiate metabolically active bone tumors from healthy bone.
• This technique may aid in assessing tumor response to therapy and understanding bone tumor biochemistry.
• These findings represent the first P-31 MR spectra of human bone tumors obtained directly from patients.