A study on psammoma body mineralization in meningiomas

Psammoma bodies (PBs) in meningioma patients often contain mineral deposits. In this paper, the mineralogical characteristics of PBs in the mineralized focus in meningioma patients were investigated by using scanning electron microscopy (SEM), environmental scanning electron microscopy (ESEM), high-resolution transmission electron microscopy (HRTEM), energy dispersive X-ray analysis (EDAX), and electron probe microanalysis (EPMA). We found that PBs had a concentric layered structure and the size ranged from several to tens of micrometers. Although no obvious trend in the variation of Ca/P ratios was observed from the center to the outer edge of the PBs, the Ca/P ratios were much lower in the early stage of PBs formation. The concentric layered structure of the PBs might be formed by a spiral arrangement of mineralized collagen fibers. Studies on PBs mineralization may provide some supporting information in understanding the origin and development of meningiomas.