Marc Guy Albert Marie Lacroix (pronounced [maʁk lakʁwa]; born 28 April 1963 in Verviers, Wallonia[citation needed]) is a Belgian biochemist (educated at University of Liège) and a researcher who specializes in breast cancer biology, metastasis and therapy.
Guy Leclercq (Laboratoire Jean-Claude Heuson de Cancérologie Mammaire, Institut Jules Bordet, Belgium), Lacroix has studied various aspects of estrogen receptor biology, ligand-binding and transcriptional activity, and life-cycle.
According to PubMed, a search engine offering access to the MEDLINE database of citations and abstracts of biomedical research articles, 7918 papers containing the expression «breast cancer» were published in 2006.
In 2004, Lacroix and colleagues collected and assembled data from hundreds of articles related to the biology, pathology and genetics of in situ, invasive and metastatic breast cancers.
Lacroix et al. concluded that despite undergoing increasing genetic alteration, most individual breast cancers rather surprisingly maintain their phenotype when they evolve from in situ to the metastatic state.