EP165/#859 Pregnancy associated breast cancer (PABC): management and obstetrical outcomes

Objectives

We aim to study the impact of the diagnosis of the PABC on the pregnancy outcome and to report the characteristics of the management of breast cancer during the pregnancy.

Methods

It is a retrospective study. We included all patients diagnosed, at our institution, during a 10-year- period (2011- 2020), with PABC defined as breast cancer diagnosed during pregnancy or in the first postpartum year. We collected the data regarding the epidemiological, clinical, imaging, pathological, obstetrical, and oncological management strategies and outcomes.

Results

PABC was confirmed in 33 patients. The average age at the diagnosis was 35.58 years [23–47]. The average term of pregnancy at the time of PABC diagnosis was 19.35 weeks of amenorrhea (WA) [6–38]. The mean tumor size was 48 mm [10–130], and 21.21% had more than one lump. Axillary lymph nodes were present in 46.9%. The most common histological type is invasive ductal carcinoma no specific type (IDC-NST) (75.8%). The luminal B (53.1%) and the triple-negative (28.1%) were the two most expressed profiles. The pregnancy was terminated in 44.6%, and the average term of delivery was 36 WA [26–39]. We report a case of stillbirth prior to any therapy. The mean weight of newborns was 3045g [870- 3880] and no malformation was reported after chemotherapy. Five patients started chemotherapy during pregnancy. Breast surgery was performed after the delivery in 90.9% (66.66% mastectomy).

Conclusions

PABC is a particular entity among breast cancer that needs a multidisciplinary team to ensure the best outcome for both the patient and the pregnancy.