Pregnancy during adjuvant tamoxifen therapy: A case of temporary interruption and postpartum metastatic recurrence

Authors

  • Dr. Morris Maganjo University of Nairobi, Department of Obstetrics and Gynaecology, Nairobi, Kenya https://orcid.org/0000-0001-7075-0200
  • Professor Rose Kosgei University of Nairobi, Department of Obstetrics and Gynaecology, Nairobi, Kenya
  • Dr. Humphrey Obwaya University of Nairobi, Department of Obstetrics and Gynaecology, Nairobi, Kenya https://orcid.org/0000-0002-0827-4116
  • Dr. Allan Ikol Kenyatta National Hospital, Department of Obstetrics and Gynaecology, Nairobi, Kenya https://orcid.org/0009-0005-4879-9792
  • Dr. Maurine Mutua University Health Services, University of Nairobi

DOI:

https://doi.org/10.59692/jogeca.v37i3.420

Keywords:

breast cancer, endocrine therapy, metastasis, pregnancy, tamoxifen

Abstract

Background: Limited data exist regarding recurrence risk in pregnant women with hormone receptor-positive breast cancer who temporarily discontinue endocrine therapy.

Case presentation: A 37-year-old gravida 4, para 3, presented for antenatal care at 13 weeks’ gestation while on adjuvant tamoxifen, which she had taken for two months before conception. Examination revealed a fundal height of 18 weeks and a healed mastectomy scar. Ultrasonography confirmed a dichorionic diamniotic twin pregnancy. Tamoxifen was discontinued, and pregnancy proceeded uneventfully until spontaneous preterm delivery at 34 weeks. Both neonates were clinically normal. Tamoxifen was resumed postpartum; however, 5 months after delivery, the patient developed metastatic recurrence and subsequently succumbed.

Conclusion: Pregnancy during breast cancer is not uncommon and poses complex clinical challenges. A multidisciplinary team is key to optimize maternal and neonatal outcomes.

Keywords: breast cancer, endocrine therapy, metastasis, pregnancy, tamoxifen

Author Biographies

Dr. Morris Maganjo, University of Nairobi, Department of Obstetrics and Gynaecology, Nairobi, Kenya

Resident,

Department of Obstetrics and Gynaecology

University of Nairobi

Professor Rose Kosgei, University of Nairobi, Department of Obstetrics and Gynaecology, Nairobi, Kenya

Prof. Rose Jepchumba Kosgei

MBChB, MMed (Obs/Gyn), Fell. Gyn Onc, MSc (Clinical Trials), PhD

Associate Professor Department of Obstetrics and Gynecology 

Coordinator Gyn. Onc Fellowship Program

University of Nairobi 

Dr. Humphrey Obwaya, University of Nairobi, Department of Obstetrics and Gynaecology, Nairobi, Kenya

Resident,

Department of Obstetrics and Gynaecology

University of Nairobi

Dr. Allan Ikol, Kenyatta National Hospital, Department of Obstetrics and Gynaecology, Nairobi, Kenya

Consultant obstetrician and gynaecologist,

Maternal fetal specialist

Kenyatta National Hospital

References

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Published

2025-09-30

How to Cite

Maganjo, M., Kosgei , R., Obwaya, H., Ikol, A. ., & Mutua, M. (2025). Pregnancy during adjuvant tamoxifen therapy: A case of temporary interruption and postpartum metastatic recurrence. Journal of Obstetrics and Gynaecology of Eastern and Central Africa, 37(3), 108–112. https://doi.org/10.59692/jogeca.v37i3.420

Issue

Vol. 37 No. 3 (2025): JOGECA Volume 37 issue 3

Section

Case report

Categories

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Copyright (c) 2025 Dr. Morris Maganjo, Professor Rose Kosgei, Dr. Humphrey Obwaya, Dr. Allan Ikol, Dr. Maurine Mutua

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This work is licensed under a Creative Commons Attribution 4.0 International License.

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