A drug called lapatinib may shrink breast cancer tumors within six weeks and could prove to be a valuable pre-surgery treatment, according to researchers at Baylor College of Medicine in Houston, who studied 45 patients with locally advanced breast cancer in which the HER-2 gene was overexpressed.

The women received lapatinib, a tyrosine kinase inhibitor that targets cell surface receptors, for six weeks. That was followed by a combination of weekly trastuzumab and three-times-a-week docetaxel for 12 weeks before primary surgery, United Press International reported.

Tests conducted before and after lapatinib treatment showed "significant tumor regression after six weeks of single-agent lapatinib," said study author Dr. Angel Rodriguez.

The study was to be presented at the European Breast Cancer Conference in Berlin.