Tags

Type your tag names separated by a space and hit enter

Tamoxifen treatment for breast cancer and risk of endometrial cancer: a case-control study.
J Natl Cancer Inst. 2005 Mar 02; 97(5):375-84.JNCI

Abstract

BACKGROUND

Tamoxifen treatment of breast cancer is associated with an increased risk of endometrial cancer, but tamoxifen-related risks of endometrial cancer are unclear in premenopausal women, in long-term users of tamoxifen, and in women for whom several years have passed since ending treatment. We conducted a case-control study in Britain to investigate these risks.

METHODS

We compared treatment information on 813 case patients who had endometrial cancer after their diagnosis for breast cancer and 1067 control patients who had breast cancer but not subsequent endometrial cancer. We assessed risk by conditional logistic regression analysis. All statistical tests were two-sided.

RESULTS

Overall, tamoxifen treatment, compared with no treatment, was associated with an increased risk of endometrial cancer (odds ratio [OR] = 2.4; 95% confidence interval [CI] = 1.8 to 3.0). Risk increased statistically significantly (P(trend)<.001) with duration of treatment (for > or =5 years of treatment compared with no treatment, OR = 3.6, 95% CI = 2.6 to 4.8). As an indication of background levels of treatment, 16% of control patients received 5 years or more of treatment. Risk of endometrial cancer adjusted for treatment duration did not diminish in follow-up to at least 5 years after the last treatment ended. Risk of endometrial cancer was not associated with the daily dose of tamoxifen and was comparable in pre- and postmenopausal women. Ever treatment with tamoxifen was associated with a much greater risk of Mullerian and mesodermal mixed endometrial tumors (OR = 13.5, 95% CI = 4.1 to 44.5) than of adenocarcinoma (OR = 2.1, 95% CI = 1.6 to 2.7) or clear cell and papillary serous tumors (OR = 3.1, 95% CI = 0.8 to 17.9).

CONCLUSIONS

There is an increasing risk of endometrial cancer associated with longer tamoxifen treatment, extending well beyond 5 years. The increased risk of endometrial cancer associated with tamoxifen treatment should be considered clinically for both premenopausal and postmenopausal women during treatment and for at least 5 years after the last treatment.

Authors+Show Affiliations

Section of Epidemiology, Brookes Lawley Building, Institute of Cancer Research, Sutton, Surrey SM2 5NG, UK. anthony.swerdlow@icr.ac.ukNo affiliation info availableNo affiliation info available

Pub Type(s)

Journal Article
Research Support, Non-U.S. Gov't
Research Support, U.S. Gov't, P.H.S.

Language

eng

PubMed ID

15741574

Citation

Swerdlow, Anthony J., et al. "Tamoxifen Treatment for Breast Cancer and Risk of Endometrial Cancer: a Case-control Study." Journal of the National Cancer Institute, vol. 97, no. 5, 2005, pp. 375-84.
Swerdlow AJ, Jones ME, British Tamoxifen Second Cancer Study Group. Tamoxifen treatment for breast cancer and risk of endometrial cancer: a case-control study. J Natl Cancer Inst. 2005;97(5):375-84.
Swerdlow, A. J., & Jones, M. E. (2005). Tamoxifen treatment for breast cancer and risk of endometrial cancer: a case-control study. Journal of the National Cancer Institute, 97(5), 375-84.
Swerdlow AJ, Jones ME, British Tamoxifen Second Cancer Study Group. Tamoxifen Treatment for Breast Cancer and Risk of Endometrial Cancer: a Case-control Study. J Natl Cancer Inst. 2005 Mar 2;97(5):375-84. PubMed PMID: 15741574.
* Article titles in AMA citation format should be in sentence-case
TY - JOUR T1 - Tamoxifen treatment for breast cancer and risk of endometrial cancer: a case-control study. AU - Swerdlow,Anthony J, AU - Jones,Michael E, AU - ,, PY - 2005/3/3/pubmed PY - 2005/3/9/medline PY - 2005/3/3/entrez SP - 375 EP - 84 JF - Journal of the National Cancer Institute JO - J Natl Cancer Inst VL - 97 IS - 5 N2 - BACKGROUND: Tamoxifen treatment of breast cancer is associated with an increased risk of endometrial cancer, but tamoxifen-related risks of endometrial cancer are unclear in premenopausal women, in long-term users of tamoxifen, and in women for whom several years have passed since ending treatment. We conducted a case-control study in Britain to investigate these risks. METHODS: We compared treatment information on 813 case patients who had endometrial cancer after their diagnosis for breast cancer and 1067 control patients who had breast cancer but not subsequent endometrial cancer. We assessed risk by conditional logistic regression analysis. All statistical tests were two-sided. RESULTS: Overall, tamoxifen treatment, compared with no treatment, was associated with an increased risk of endometrial cancer (odds ratio [OR] = 2.4; 95% confidence interval [CI] = 1.8 to 3.0). Risk increased statistically significantly (P(trend)<.001) with duration of treatment (for > or =5 years of treatment compared with no treatment, OR = 3.6, 95% CI = 2.6 to 4.8). As an indication of background levels of treatment, 16% of control patients received 5 years or more of treatment. Risk of endometrial cancer adjusted for treatment duration did not diminish in follow-up to at least 5 years after the last treatment ended. Risk of endometrial cancer was not associated with the daily dose of tamoxifen and was comparable in pre- and postmenopausal women. Ever treatment with tamoxifen was associated with a much greater risk of Mullerian and mesodermal mixed endometrial tumors (OR = 13.5, 95% CI = 4.1 to 44.5) than of adenocarcinoma (OR = 2.1, 95% CI = 1.6 to 2.7) or clear cell and papillary serous tumors (OR = 3.1, 95% CI = 0.8 to 17.9). CONCLUSIONS: There is an increasing risk of endometrial cancer associated with longer tamoxifen treatment, extending well beyond 5 years. The increased risk of endometrial cancer associated with tamoxifen treatment should be considered clinically for both premenopausal and postmenopausal women during treatment and for at least 5 years after the last treatment. SN - 1460-2105 UR - https://www.unboundmedicine.com/medline/citation/15741574/Tamoxifen_treatment_for_breast_cancer_and_risk_of_endometrial_cancer:_a_case_control_study_ L2 - https://academic.oup.com/jnci/article-lookup/doi/10.1093/jnci/dji057 DB - PRIME DP - Unbound Medicine ER -