Does the cell number 10(9) still really fit one gram of tumor tissue?

Cell Cycle. 2009 Feb 1;8(3):505-6. doi: 10.4161/cc.8.3.7608. Epub 2009 Feb 11.


A tumor reaching the size of 1 cm(3) (approximately 1 g wet weight) is commonly assumed to contain 1 x 10(9) cells. This paper comments on the probable origin of this "magic" number and on some possible reasons why it has remained in use until now. However, mostly in epithelial tumors (85% of all human tumors) a cell number one order of magnitude smaller would be more realistic.

Publication types

  • Letter
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Cell Size*
  • Humans
  • Models, Biological*
  • Neoplasms / pathology*
  • Rats