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Breast Cancer Treatment and Pregnancy (PDQ®)

Health Professional Version

Early Stage Breast Cancer (Stage I and II)

Surgery is recommended as the primary treatment of breast cancer in pregnant women. Since radiation in therapeutic doses may expose the fetus to potentially harmful scatter radiation,[1] modified radical mastectomy is the treatment of choice. Conservative surgery with postpartum radiation therapy has been used for breast preservation.[2] An analysis has been performed that helps to predict the risk of waiting to have radiation.[3,4]

If adjuvant chemotherapy is necessary, it should not be given during the first trimester to avoid the risk of teratogenicity. Chemotherapy given after the first trimester is generally not associated with a high risk of fetal malformation but may be associated with premature labor and fetal wastage. If considered necessary, chemotherapy may be given after the first trimester. Data on the immediate and long-term effects of chemotherapy on the fetus are limited.[2,4-9]

Studies using adjuvant hormonal therapy alone or in combination with chemotherapy for breast cancer in pregnant women are also limited. Therefore, no conclusion has been reached regarding these options.[10] Radiation therapy, if indicated, should be withheld until after delivery since it may be harmful to the fetus at any stage of development.[1]


  1. Kal HB, Struikmans H: Radiotherapy during pregnancy: fact and fiction. Lancet Oncol 6 (5): 328-33, 2005. [PUBMED Abstract]
  2. Gwyn K, Theriault R: Breast cancer during pregnancy. Oncology (Huntingt) 15 (1): 39-46; discussion 46, 49-51, 2001. [PUBMED Abstract]
  3. Nettleton J, Long J, Kuban D, et al.: Breast cancer during pregnancy: quantifying the risk of treatment delay. Obstet Gynecol 87 (3): 414-8, 1996. [PUBMED Abstract]
  4. Kuerer HM, Gwyn K, Ames FC, et al.: Conservative surgery and chemotherapy for breast carcinoma during pregnancy. Surgery 131 (1): 108-10, 2002. [PUBMED Abstract]
  5. Clark RM, Chua T: Breast cancer and pregnancy: the ultimate challenge. Clin Oncol (R Coll Radiol) 1 (1): 11-8, 1989. [PUBMED Abstract]
  6. Giacalone PL, Laffargue F, Bénos P: Chemotherapy for breast carcinoma during pregnancy: A French national survey. Cancer 86 (11): 2266-72, 1999. [PUBMED Abstract]
  7. Rugo HS: Management of breast cancer diagnosed during pregnancy. Curr Treat Options Oncol 4 (2): 165-73, 2003. [PUBMED Abstract]
  8. Cardonick E, Iacobucci A: Use of chemotherapy during human pregnancy. Lancet Oncol 5 (5): 283-91, 2004. [PUBMED Abstract]
  9. Berry DL, Theriault RL, Holmes FA, et al.: Management of breast cancer during pregnancy using a standardized protocol. J Clin Oncol 17 (3): 855-61, 1999. [PUBMED Abstract]
  10. Isaacs RJ, Hunter W, Clark K: Tamoxifen as systemic treatment of advanced breast cancer during pregnancy--case report and literature review. Gynecol Oncol 80 (3): 405-8, 2001. [PUBMED Abstract]
  • Updated: September 2, 2014