Tumor proliferative fraction in solid malignant neoplasms. A comparative study of Ki-67 immunostaining and flow cytometric determinations.
Tumor proliferative fraction (TPF) has been shown to correlate with prognosis in some malignancies. A method for its determination that is practical, accurate, and reproducible is still being sought. In this comparative study of techniques, TPF values were determined in mirror-image samples of 126 consecutive solid malignant neoplasms using flow cytometry and immunostaining with Ki-67, a monoclonal antibody that recognizes an unknown nuclear antigen expressed during the entire cell proliferation cycle but not in resting cells. The mean TPF values for all cases were 19.5 +/- 15.6% (percentage of tumor cells stained) by Ki-67 (range, 1-86%) and 15.7 +/- 9.6% (S + G2M) by flow cytometry (range, 3-60%), which correlated significantly at r = 0.53 and P = 0.005. The correlation was less strong in tumors with low S-phase values (less than or equal to 10%, r = 0.28) than in tumors with intermediate and high S-phase values (r = 0.66). Ki-67 staining percentages did not correlate with patient age, sex, or tissue origin of the tumor. Ki-67 staining appears comparable to flow cytometry determination of TPF in solid malignancies with intermediate and high S-phase values. In tumors with low S-phase values, Ki-67 immunostaining shows higher TPF values, which perhaps reflect an increase in the proportion of G1-phase cells or dilutional effect of nonneoplastic cells in the tumors with low proliferative fraction.
Sahin
A A
AA
Department of Pathology, University of Texas M.D. Anderson Cancer Center, Houston.
Ro
J Y
JY
el-Naggar
A K
AK
Wilson
P L
PL
Teague
K
K
Blick
M
M
Ayala
A G
AG
D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D002455:Cell Division; D016009:Chi-Square Distribution; D004261:DNA Replication; D004273:DNA, Neoplasm / Q000032:analysis; D005260:Female; D005434:Flow Cytometry; D016195:G2 Phase; D006801:Humans; D007150:Immunohistochemistry; D019394:Ki-67 Antigen; D008297:Male; D008875:Middle Aged; D008940:Mitotic Index; D009369:Neoplasms / Q000473:pathology*; D009687:Nuclear Proteins / Q000032:analysis*; D016196:S Phase; D013194:Staining and Labeling
D004273:DNA, Neoplasm; D019394:Ki-67 Antigen; D009687:Nuclear Proteins