# Radiation Oncology/Breast/Pregnancy

Breast Cancer in Pregnancy

## Pregnancy-associated breast cancer (PABC)

* Heather R Macdonald et al. Pregnancy associated breast cancer. Breast J. 2020 Jan;26(1):81-85. (PMID: 31943583)
** Pregnancy associated breast cancer (PABC) defined as breast cancer occurring during pregnancy or within the first 1-2 years postpartum.
** Delay in diagnosis is common.
** Treatment is timed around gestational age.
*** Surgery and chemotherapy are considered safe after the first trimester.
*** Radiation, anti-her-2, and endocrine therapy are delayed until after delivery due to adverse fetal effects.
** Iatrogenic prematurity likely causes most long-term fetal sequelae.
** Multi-disciplinary care and social support are critical for patients and families with PABC.
* Erin A Keyser et al. Pregnancy-associated breast cancer. Rev Obstet Gynecol. 2012;5(2):94-9. (PMID: 22866188)

## Clinicopathologic studies

* MDACC (1986-2001)
** 2003, PMID 12942575 -- "Breast carcinoma in pregnant women: assessment of clinicopathologic and immunohistochemical features." (Middleton LP, Cancer. 2003 Sep 1;98(5):1055-60.)
*** 39 pts with breast cancer diagnosed during pregnancy.
*** Conclusion: Breast carcinomas occurring during pregnancy share many histologic and prognostic similarities with breast carcinoma occurring in other young women.

## Case series

* Kaiser Permanente (Los Angeles) (1970-80)
** 19 pts under age 40 diagnosed with breast cancer during pregnancy, compared with 155 pts age < 40 not pregnant.
** 1985, PMID 4051725 -- "Breast cancer and pregnancy." (Nugent P, Arch Surg. 1985 Nov;120(11):1221-4.)
*** Trend to higher stage in pregnant pts (vs non-pregnant pts age < 40). No difference in survival stage for stage.\
*** 71% of pregnant pts were ER-.
* MDACC
** 2006 (1989-2005) PMID 16894524 -- "Treatment of pregnant breast cancer patients and outcomes of children exposed to chemotherapy in utero." (Hahn KM, Cancer. 2006 Sep 15;107(6):1219-26.)
*** 57 pts. Treated with chemotherapy in 2nd-3rd trimesters.
** 1999 (1989-99), PMID 10071276 -- "Management of breast cancer during pregnancy using a standardized protocol." (Berry DL, J Clin Oncol. 1999 Mar;17(3):855-61.)
*** 24 pregnant pts with breast cancer, 22 primary and 4 recurrent. Of the 22 with primary cancer, 18 treated with MRM (14 antepartum, 4 postpartum). 2 pts treated with lumpectomy followed by chemotherapy and received RT postpartum.
Outcomes compared with non-pregnant breast cancer patients:
* MDACC
** 2009 PMID 19204903 -- "The impact of pregnancy on breast cancer outcomes in women<or=35 years." (Beadle BM, Cancer. 2009 Mar 15;115(6):1174-84.)
*** 104 cases of breast cancer in pregnant women < 35 yrs.
*** 25% underwent breast conservation.
*** Conclusion: Young patients with PABC had no statistically significant differences in LRR, DM, or OS compared with those with non-PABC; however, pregnancy contributed to a delay in breast cancer diagnosis, evaluation, and treatment.

## Reviews

* MDACC, 2010 PMID 21147871 -- "Breast cancer and pregnancy: current concepts in diagnosis and treatment." (Litton JK, Oncologist. 2010;15(12):1238-47.)
* MDACC, 2009 PMID 19392610 -- "Breast cancer diagnosis during pregnancy." (Litton JK, Womens Health (Lond Engl). 2009 May;5(3):243-9.)
* Italy, 2010 PMID 21050304 -- "Breast cancer in pregnancy." (Rovera F, Breast J. 2010 Sep-Oct;16 Suppl 1:S22-5.)
* Dana-Farber, 2005 PMID 15971447 -- "Pregnancy and breast cancer: epidemiology, treatment, and safety issues." (Partridge A, Oncology (Williston Park). 2005 May;19(6):693-7.)
** Discussion: link (Theriault R and Buzdar A)
* Baylor, 2003 PMID 12511159 -- "Breast cancer in pregnancy: a literature review." (Woo JC, Arch Surg. 2003 Jan;138(1):91-8.)
* MDACC, 2001 PMID 11271981 Full text -- "Breast cancer during pregnancy." (Gwyn K, Oncology (Williston Park). 2001 Jan;15(1):39-46.)
* MSKCC, 1994 PMID 8004627 Full text -- "Breast cancer during pregnancy." (Petrek JA, Cancer. 1994 Jul 1;74(1 Suppl):518-27.)

## Guidelines

* International
** 2006, PMID 16342247 -- "Breast carcinoma during pregnancy. International recommendations from an expert meeting." (Loibl S, Cancer. 2006 Jan 15;106(2):237-46.)
** Recommendations presented.
* SOGC (Canada) - Society of Obstetricians and Gynecologists of Canada
** 2002 PMID 12196882 PDF -- "Breast cancer, pregnancy, and breastfeeding." (J Obstet Gynaecol Can. 2002 Feb;24(2):164-80)