The value of cell cycle analysis by propidium-iodine staining of CD56+ cells in pediatric brain tumors.

Purpose: Cell cycle analysis by flow cytometry has not been adequately studied in pediatric brain tumors. We investigated the value of cell cycle analysis by propidium-iodine (PI) staining of CD56+ (gated) cells for the characterization of pediatric brain tumor's malignancy.

Methods: Patients that underwent surgery for an intracranial lesion and tissue sample was available were included in the study. All tumor samples were histopathologically verified before flow cytometric analysis.

Results: There were 46 pediatric brain tumor cases. As control we used samples from three cases of brain tissue obtained during surgery for epilepsy. All tumors had significant lower G0/G1 and significant higher S-phase, G2/M fraction, S+G2/M and S+G2/M/G0/G1-phase fraction than normal brain tissue. Low-grade tumors had significant lower S-phase than high grade tumors. Grade IV tumors had significant lower G0/G1 fraction and higher S+G2/M/G0/G1 index than grade III tumors. DNA diploidy was detected in 24 tumors and DNA aneuploidy was detected in 23 tumors. There was a significant correlation between Ki-67 index and both S+G2/M and S+G2/M/G0/G1 phase fraction.

Conclusions: Cell cycle analysis by PI staining of CD56+ cells is a promising method for the assessment of pediatric brain tumors malignancy and could be a valuable adjunct to histopathological evaluation.