MIB1, A PROMISING MARKER FOR THE CLASSIFICATION OF CERVICAL INTRAEPITHELIAL NEOPLASIA

SUMMARY Form alin-fixed and paraffin-em bedded tissue specim ens o f norm al and dysplastic cervical epithelia (five C IN 1, seven C IN 2, five C IN 3, and five norm al) were assessed by an im m unoperoxidase technique, using the m onoclonal antibody M IB 1 , regonizing a fo rm alin -tix atio n -resistan t epitope on th e cell pro liferatio n -asso ciated K i-67 antigen. An im ag e analysis system w as u sed to m easure four p aram eters associated with p ro liferative activity: the K i-67 labelling index (L I), th e num ber of K i-67-positive nuclei per unit length of basem ent m em brane, and the m axim um value and 90th percentile o f the relativ e distances of K i-67-positive nuclei from the basem ent m em brane. All these four p ro liferatio n -related p aram eters were highly c o rre la te d w ith the grade o f dysplastic change in the epithelium (0*90 <0*0001). T he best correlation was found for the 90th percentile of the relative d istan ce and with this p a ra m e te r all C IN lesions could be co rrectly classified. T he m eans and s ta n d a rd deviations o f the Ki-67 L is in normal epithelium , C IN 1, C1N 2, and C IN 3 lesions w ere 0*07 ± 0*03, 0*16 ± 0-03, 0*25 ± 0*06, and 0-39 ± 0*06, respectively. T hese findings su p p o rt the theory th a t C IN involves a progressive dysfunction o f the proliferative activ ity o f cervical epithelial cells. Im ag e analysis o f M IB 1 is a prom ising altern ativ e m ethod for th e objective, reproducible, and reliab le classification o f dysplastic changes in cervical epithelium . joey w o r d s— C IN ; p roliferation; K i-67; M IB 1; m onoclonal antibody; im m unohistochem istry; quan titativ e analysis