Prognostic significance of Ki‐67 (MIB‐1) proliferation index in childhood primitive neuroectodermal tumors of the central nervous system

摘要: Background. Primitive neuroectodermal tumors (PNET) of the central nervous system, including medulloblastomas, are most common malignant brain childhood. Whereas some patients experience prolonged disease control after surgery and adjuvant therapy, others with that appear comparable will relapse eventually die from progressive disease. Procedure. Because proliferative activity may provide a potential correlate biologic aggressiveness, PNETs 78 well-characterized were evaluated by Ki-67 (MIB-1) immunohistochemistry. Proliferation indices (PI) determined counting positive tumor cells either in highest staining region (hot spot PI), or at least 15 randomly chosen fields (random PI). Results. Twenty-five showed amore than twofold higher value hot PI (median 9.3%; range 0.6-56%), compared to random 5.6%; 0.2-41.3%). Univariate Cox regression analysis revealed high had significantly greater risk progression death low (hazard ratio 1.58, P 0.04). The hazard remained significant adjusting for M-stage multivariate analysis. In contrast PI, proved not be prognostic predictor. Conclusions. Hot is independent factor PNETs. Its assessment uncomplicated, reliable, supplement routine histologic examination as means improving accuracy predicting behavior childhood