Breast cancer outcomes after diagnosis of hormone positive breast cancer and subsequent pregnancy in the tamoxifen era

• Published in: Clinical breast cancer Vol. 17; no. 4; pp. e185 - e189
• Main Authors: Nye, Lauren, MD, Rademaker, Alfred, PhD, Gradishar, William J., MD
• Format: Journal Article
• Language: English
• Published: United States Elsevier Inc 01.07.2017
• Subjects: Adult; Antineoplastic Agents, Hormonal - therapeutic use; Biomarkers, Tumor - metabolism; Breast Neoplasms - drug therapy; Breast Neoplasms - metabolism; Breast Neoplasms - pathology; Cancer; Carcinoma, Ductal, Breast - drug therapy; Carcinoma, Ductal, Breast - metabolism; Carcinoma, Ductal, Breast - pathology; Carcinoma, Intraductal, Noninfiltrating - drug therapy; Carcinoma, Intraductal, Noninfiltrating - metabolism; Carcinoma, Intraductal, Noninfiltrating - pathology; Carcinoma, Lobular - drug therapy; Carcinoma, Lobular - metabolism; Carcinoma, Lobular - pathology; Case-Control Studies; Chemotherapy, Adjuvant; Endocrine therapy; Female; Fertility; Follow-Up Studies; Hematology, Oncology and Palliative Medicine; Humans; Kansas - epidemiology; Middle Aged; Obstetrics and Gynecology; Pregnancy; Pregnancy Complications, Neoplastic - epidemiology; Prevalence; Prognosis; Receptor, ErbB-2 - metabolism; Receptors, Estrogen - metabolism; Receptors, Progesterone - metabolism; Recurrence; Retrospective Studies; Survival Rate; Survivorship; Tamoxifen - therapeutic use; Endocrine therapy; Recurrence; Survivorship; Fertility; Cancer
• ISSN: 1526-8209; 1938-0666
• DOI: 10.1016/j.clbc.2016.12.014

Abstract Background Counseling patients about the risk of future pregnancy on hormone receptor-positive breast cancer outcomes is difficult with minimal data and understanding of pregnancy on the breast environment. Patients and Methods This retrospective analysis included 32 pre-menopausal women with a diagnosis of estrogen receptor-positive breast cancer between 2000 and 2010 and subsequent pregnancy within 5 years. The control cohort included 29 women matched for age and stage of breast cancer but did not become pregnant. Results There was no statistically significant difference in age, diagnosis, stage, grade or HER2 status between groups. Nineteen (63%) women in the pregnancy cohort received endocrine therapy and 23 (82%) in the control cohort (P=0.25). The mean (range) length of endocrine therapy in the control cohort was 42.3 (0-120) months, compared to the pregnancy cohort, 20.9 (0-72) months (P=0.008). Four women (14%) in the control cohort had a breast cancer recurrence compared to eight women (26%) in the pregnancy cohort, (P=0.34). The five-year disease free survival was 92% (95% CI 81% to 100%) in the control cohort compared to 84% (95% CI 72% to 97%) in the pregnancy cohort, which was not statistically significant (P=0.69). Conclusions This study did not demonstrate poorer DFS in pre-menopausal women with estrogen receptor-positive breast cancer that became pregnant within five years of diagnosis. It is unique because all included patients had estrogen receptor-positive disease and were offered adjuvant hormone therapy. Further prospective investigation will be beneficial to patients and physicians as they discuss pregnancy as a key survivorship issue.