NCIt definition : The percentage of cells in a sample currently undergoing mitosis.;
Alternative definition : NCI-GLOSS: A measure of the percentage of cells in a tumor that are in the phase of
the cell cycle during which DNA is synthesized. The S-phase fraction may be used with
the proliferative index to give a more complete understanding of how fast a tumor
is growing.;
NCIt note : It is a measurement of proliferation and can be used as a proliferation marker. A
higher index generally correlates with more aggressive tumors.;
Codes from synonyms : CDR0000386225; CDR0000044771;