A pilot study of the effects of short-term tamoxifen therapy on Ki-67 labelling index in women with primary breast cancer

dc.contributor.authorDardes, Rita de Cássia de Maio [UNIFESP]
dc.contributor.authorHoriguchi, J. [UNIFESP]
dc.contributor.authorJordan, V. C. [UNIFESP]
dc.contributor.institutionNorthwestern Univ
dc.contributor.institutionUniversidade Federal de São Paulo (UNIFESP)
dc.contributor.institutionGunma Univ
dc.description.abstractIn this study we demonstrate the change in estrogen receptor (ER) level and cell proliferation in human breast cancer after a short-term tamoxifen therapy. Ten pre and post-treatment breast tumor samples were examined immunohistochemically using ER and Ki-67 antibodies. Before tamoxifen treatment, six (60%) of ten patients were positive for ER. Tamoxifen increased the ER level in one patient and decreased the level in 4 patients. There was no significant change in ER level by tamoxifen therapy. On the other hand, Ki-67 labelling index (LI) significantly decreased after tamoxifen treatment. When Ki-67 LI was analyzed according to ER level, there was no difference between pre- and post-tamoxifen treatment in ER-negative patients, however, a significant decrease of Ki-67 LI by tamoxifen treatment was seen in ER-positive patients. Patients who showed down-regulation of ER expression tended to show a decrease of Ki-67 LI after tamoxifen therapy. In conclusion, short-term tamoxifen therapy decreased the proliferation of breast cancer, in ER-positive breast tumor samples.en
dc.description.affiliationNorthwestern Univ, Sch Med,Robert H Lurie Comprehens Canc Ctr, Lynn Sage Breast Canc Res Program, Dept Biol Chem & Mol Pharmacol, Chicago, IL 60611 USA
dc.description.affiliationUniv Fed Sao Paulo, Dept Gynecol, Sao Paulo, Brazil
dc.description.affiliationGunma Univ, Sch Med, Dept Surg 2, Gunma, Japan
dc.description.affiliationUnifespUniv Fed Sao Paulo, Dept Gynecol, Sao Paulo, Brazil
dc.description.sourceWeb of Science
dc.identifier.citationInternational Journal Of Oncology. Athens: Professor D A Spandidos, v. 16, n. 1, p. 25-30, 2000.
dc.publisherProfessor D A Spandidos
dc.relation.ispartofInternational Journal Of Oncology
dc.rightsAcesso restrito
dc.subjectbreast canceren
dc.subjectestrogen receptoren
dc.titleA pilot study of the effects of short-term tamoxifen therapy on Ki-67 labelling index in women with primary breast canceren