Radiology and Oncology  |  Ljubljana  |  Slovenia  |  www.radioloncol.com
Radiol Oncol 2021; 55(3): 362-368. doi: 10.2478/raon-2021-0022
362
research article
Breast cancer during pregnancy: retrospective 
institutional case series
Erika Matos1,2, Tanja Ovcaricek1
1 Department of Medical Oncology, Institute of Oncology Ljubljana, Ljubljana, Slovenia
2 Faculty of Medicine, University of Ljubljana, Ljubljana, Slovenia
Radiol Oncol 2021; 55(3): 362-368.
Received 29 August 2020 
Accepted 29 March 2021
Correspondence to: Assist. Prof. Erika Matos, M.D., Ph.D., Department of Medical Oncology, Institute of Oncology Ljubljana,  
Zaloska 2, SI-1000 Ljubljana, Slovenia. E-mail: ematos@onko-i.si
Disclosure: No potential conflict of interest were disclosed.
This is an open access article under the CC BY-NC-ND license (http://creativecommons.org/licenses/by-nc-nd/4.0/).
Background. Pregnancy associated breast cancer is a rare disease. It presents a unique entity of breast cancer 
with aggressive phenotype. The main aim was to evaluate how the international guidelines were followed in daily 
practice. 
Patients and methods. Data concerning patients’ and tumours’ characteristics, management, delivery and ma-
ternal outcome were recorded from institutional electronic database. In this paper a case series of pregnant breast 
cancer patients treated at single tertiary institution between 2007 and 2019 are presented and the key recommenda-
tions on managing such patients are summarized.
Results. Fourteen patients met the search criteria. The majority of tumours were high grade, triple negative or HER2 
positive, two patients were de novo metastatic. Treatment plan was made for each patient by multidisciplinary team. 
Eight patients were treated with systemic chemotherapy with no excess toxicity or severe maternal/fetal adverse ef-
fects. In all but two patients, delivery was on term and without major complications. Only one event, which was not in 
whole accordance with international guidelines, was identified. It was the use of blue dye in one patient.
Conclusions. Women with pregnancy associated breast cancer should be managed like non-pregnant breast 
cancer patients and should expect a similar outcome, without causing harm to the unborn child. To achieve a good 
outcome in pregnancy associated breast cancer, a multidisciplinary approach is mandatory.
Key words: breast cancer; pregnancy; clinical characteristics; prognosis; therapeutic strategy
Introduction
Breast cancer is the most common malignancy 
among women in the developed world and is one 
of the most common cancer diagnosis during preg-
nancy.1,2 Nevertheless, it is relatively rare, the re-
ported incidence of pregnancy-associated breast 
cancer (PABC) is 15 to 35 breast cancer patients per 
100,000 births.3,4 Although rare, the incidence of 
PABC is increasing as women are delaying child-
birth.5 PABC is defined as breast cancer diagnosed 
during pregnancy or in the first postpartum year 
and it represents the second most common ma-
lignancy during pregnancy worldwide, second to 
cervical cancer.1,6 Diagnostic and treatment recom-
mendations have been mainly based on evidence 
from retrospective single institutional or small 
case-control studies and expert consensus, as ran-
domized trials on this entity are understandably 
lacking. In the present paper, we present a case 
series of patients diagnosed with breast cancer 
during pregnancy treated at Institute of Oncology 
Ljubljana between 2007 and 2019. The aim of the 
study was to evaluate the adherence of the man-
agement of PABC in daily clinical practice to the 
international clinical guidelines.
Diagnostic procedures for pregnant breast can-
cer patients should not significantly differ from 
those for non-pregnant women and the first step in 
treatment planning is to determine the extent of the 
Radiol Oncol 2021; 55(3): 362-368.
Matos E et al./ Breast cancer during pregnancy 363
disease.6 As in non-pregnant women, a pathomor-
phological characterisation of breast cancer is cru-
cial for optimal decision about systemic treatment. 
Therefore, a core needle biopsy of the tumour has 
to be done.7 The biology of PABC is considered dif-
ferent from that of non-pregnant women with usu-
ally more aggressive phenotype.8-12 Recommended 
diagnostic procedures in pregnant woman with 
breast cancer are presented in Table 1.7 Since the in-
cidence of mutation in BRCA 1 or 2 gene is higher 
in younger breast cancer patients genetic testing 
should be offered to pregnant women with breast 
cancer.7,13 Once a diagnosis of breast cancer has 
been made, it is important not to delay treatment. 
It is recommended that optimal treatment strategy 
for individual patient is planned by a multidisci-
plinary team.14
There is no epidemiological, clinical or prog-
nostic evidence to suggest that pregnancy, or its 
termination, will alter the natural history of breast 
cancer or improve survival. Further, pregnancy by 
itself need not compromise effective breast cancer 
treatment, although the selection of and order of 
modalities need to consider fetal safety.6 The most 
important decision upon diagnosis is thus selec-
tion of and order of modalities which need to con-
sider fetal safety.6,14,15 The decision about optimal 
treatment sequence should depend mainly on the 
extent of the disease and gestational age. Surgery 
is preferable in the 1st trimester, however, for pa-
tients in the 2nd or 3rd trimester, the treatment strat-
egy should depend mainly on the extent of the dis-
ease.14 Historically, a modified radical mastectomy 
was considered the standard of care for PABC be-
cause this approach eliminates the need for postop-
erative radiotherapy, and definitively managed the 
axillary region. However, breast conservation is a 
valid surgical option for many, although limited by 
the postoperative radiotherapy which is contrain-
dicated during all trimesters of pregnancy.
Systemic treatment should not begin before the 
end of 1st trimester, upon completion of organo-
genesis, however chemotherapy in the 2nd and 3rd 
trimester is considered safe therapeutic options for 
the majority of patients with PABC and thus post-
poning treatment until after delivery is not advised 
since it was associated with a worse outcome of the 
malignant disease.7,16,17 It is recommended to end 
with chemotherapy before the 36th week of gesta-
tion or within 3 weeks of planned delivery to avoid 
potential hematologic complications at the time of 
delivery.15 The greatest experience of chemothera-
py in pregnancy has been with anthracyclines and 
there is limited data on the use of taxanes in preg-
nancy and thus taxane use is not recommended 
during pregnancy but, if indicated, may be used 
after delivery.
Endocrine therapy is also not recommended 
during pregnancy. The literature regarding breast 
radiotherapy during pregnancy is scarce and ac-
cording to current international guidelines, radio-
therapy is not recommended during pregnancy.7 
Delivery should be scheduled on the estimated 
date of delivery. Early induction of delivery is not 
recommended unless so indicated for other medi-
cal reasons.15,18 Table 2 presents recommended 
treatment modality according to gestational age.
Although in the past PABC was thought to have 
a poor prognosis recent studies showed that prog-
nosis is comparable to non-pregnant patients when 
adjusted for age and disease stage.18,19
Patients and methods
This is a retrospective case series of patients 
who were treated for breast cancer at Institute of 
TABLE 1. Diagnostic procedures for pregnant breast cancer patients
Diagnostic procedures Patients selection
Breast US with CNB All patients
Mammography All patients
Chest X-ray All patients
CNB: tumor grade, ER, PR, HER2 status All patients
Laboratory test (CBC, ALP, LFT, CA 15-3) All patients
Liver US Liver metastases suspected
Bone MRI Bone metastases suspected
ALP = alkaline phosphatase; CBC = complete blood counts; CNB = core needle biopsy; ER = 
estrogen receptor; LFT = liver function tests; MRI = magnetic resonance imaging; PR = progesterone 
receptor; US = ultrasound
TABLE 2. Treatment of pregnant breast cancer patients
Gestational 
age Surgery
Systemic 
treatment
Treatment after 
delivery
1st trimester
Mastectomy
+
SNB/ALND
Adjuvant ChT 
beginning in 
2nd trimester
Adjuvant ET/anti-HER2 
therapy (if indicated)
+
RT (if indicated)
2nd and  
3rd trimester
Mastectomy/BCS
+
SNB/ALND
ChT
(adjuvant/neo-
adjuvant)
Adjuvant ET/anti-HER2 
therapy (if indicated)
+
RT (if indicated)
Late  
3rd trimester
Mastectomy/BCS
+
SNB/ALND
Adjuvant ET/anti-HER2 
therapy (if indicated)
+
RT (if indicated)
ALND = axillary lymph node dissection; BCS = breast conserving surgery; ChT = chemotherapy; ET 
= endocrine therapy; RT = radiotherapy; SNB = sentinel node biopsy
Radiol Oncol 2021; 55(3): 362-368.
Matos E et al./ Breast cancer during pregnancy364
Oncology Ljubljana between 2007 and 2019 and 
were pregnant at the time of confirmed malignant 
disease. Data were recorded from institutional 
electronic database using the following search cri-
teria: “breast cancer” and “pregnancy” and “ges-
tational” or “breast cancer during pregnancy”. 
Patients and tumours characteristics as well as data 
about treatment and delivery were collected from 
individual patient’s charts.
Data were analysed applying descriptive statis-
tics. SPSS version 19.0 was used for analysis (IBM, 
Armonk, NY).
The study was approved by the Institutional 
Review Board Committee and was carried out ac-
cording to the Declaration of Helsinki.
Results
Fourteen patients matched the search criteria in the 
period between January 1, 2007 and December 31, 
2019. The average age of the patients was 33 (from 
27 to 39) years. The gestational age upon diagno-
sis was between 6 and 40 weeks, with an average 
of 21 weeks. The details of the individual patients 
regarding the stages and histopathological charac-
teristics of tumours and types of systemic and sur-
gical treatment as well as radiotherapy are listed 
in Table 3. In almost half of the patients, the tumor 
was classified as triple-negative and most of the 
tumours were poorly differentiated. Almost half 
of the patients had HER2 positive tumours. All 
patients were offered genetic testing. Ten patients 
decided to do it. Out of them, four were found to be 
BRCA1 or BRCA2 gene mutation carriers. 
Eight patients received chemotherapy during 
pregnancy. All were treated with anthracyclines 
in combination with cyclophosphamide, and only 
one received taxanes (paclitaxel). As part of sup-
portive treatment, they mainly received antiemetic 
ondansetron and corticosteroids. Patients tolerated 
the treatment with no significant adverse effects. In 
addition to alopecia which was reported in all pa-
tients treated with chemotherapy, anaemia was the 
second most common adverse event, three patients 
had grade 2 anaemia.20 
Two patients were diagnosed with primary 
metastatic breast cancer. In both cases, the disease 
was detected in the 3rd trimester; they continued 
with pregnancy and gave birth on term (more than 
38 weeks of gestation). Primary metastatic disease 
was suspected based on symptoms (hip pain) and 
abnormal laboratory values. Both patients had 
high levels of tumour marker Ca 15-3 (1673, 157; 
normal level below 30 kU/L) and elevated levels of 
alkaline phosphatase (ALP; 2.02, 2.91; normal level 
below 1.74 ukat/L) at presentation.
Most of deliveries occurred on the scheduled 
date, in most cases by vaginal delivery. One patient 
decided to terminate pregnancy at week 10 to start 
treatment, one patient gave birth prematurely at 
week 27 due to placenta praevia. In another patient 
delivery was induced at week 34 due to recom-
mended adjuvant trastuzumab therapy.
No serious post-natal complications were re-
ported. Twelve patients received systemic treat-
ment (cytostatic, endocrine and/or antiHER2 
treatment) post-partum. The median period from 
delivery to initiation of post-partum systemic treat-
ment was 16 days (from 7 to 24 days). The median 
follow-up period was 64 months. Two patients 
died due to breast cancer, one of them was primary 
metastatic, in the second case, the patient died due 
to central nervous system relapse that occurred 
only two months after completion of neoadjuvant 
chemotherapy and surgery. At presentation there 
were no signs or symptoms of metastatic disease. 
All the others continue with regular follow-ups at 
Institute of Oncology Ljubljana.
Discussion
In the present paper, we present 14 cases of breast 
cancer patients diagnosed during pregnancy. With 
regard to the primary aim of the study, which was 
to evaluate the adherence of the treatment of PABC 
in daily clinical practice to the international clini-
cal guidelines, we found that most patients were 
treated accordingly.
Over the observed period 14 cases were identi-
fied. According to the incidences of PABC reported 
in the literature one would expect between one to 
five cases per year in Slovenia.2,4 The number of 
cases in our study is low which may be due to case 
identification method and/or a fact that only pa-
tients who were pregnant at the time of diagnosis 
were included, which does not fit to the definition 
of PABC. For the purpose of this study, we focused 
on the management of pregnant women with new-
ly diagnosed breast cancer.
Breast cancer diagnosed during pregnancy is 
most often detected as a palpable mass. This was 
true for all our 14 patients. Due to hormonal chang-
es palpation of breasts during pregnancy and 
breastfeeding is often unreliable and this is one of 
the reasons why PABC is often diagnosed in more 
advanced stage in comparison to other patients.6,21 
Radiol Oncol 2021; 55(3): 362-368.
Matos E et al./ Breast cancer during pregnancy 365
TABLE 3. Individual patients and tumours characteristics with details of treatment
Patient
Patient’s 
age at BC 
diagnosis 
(years)
GA at BC 
diagnosis
(weeks)
BC stage,
tumor grade
HR
HER2
BRCA
Systemic 
treatment 
during 
pregnancy
Mode of 
delivery
Complications 
at delivery, 
post-partum
Type of BC 
surgery
Post-partum 
treatment
1 34 28
T2N1M0
IIB
G3
ER/PR neg
HER2 poz
BRCA pos
EC Vaginal - MRM
Doce, 
trastuzumab
RT
2 28 13
T2N0M0
IIA
G3
ER/PR neg
HER2 neg
BRCA neg
EC CS
Placenta 
praevia, 
delivery at 
27 weeks of 
gestation
BCS and ALND EC, pacliRT
3 37 32
T2N0M0
IIA
G3
ER/PR neg
HER2 neg
BRCA neg
EC Vaginal - BCS and SNB EC, pacliRT
4 38 40
T3N1M0
IIIA
G2
ER/PR pos
HER2 pos
BRCA neg
- Vaginal - MRM
FEC, doce, 
trastuzumab, 
tamoxifen, RT
5 27 14
T1N0M0
IA
G3
ER/PR neg
HER2 neg
BRCA pos
EC Vaginal -
Mastectomy 
and SNB and 
reconstruction 
(expander)
-
6 34 8
T2N0M0
IIA
G3
ER/PR pos
HER2 pos
BRCA ND
- NR
Pregnancy 
termination 
advised, 10 
weeks of 
gestation
MRM
FEC, doce, 
trastuzumab, 
tamoxifen, RT
7 30 24
T3N0M0
IIB
G3
ER/PR neg
HER2 neg
BRCA pos
AC, pacli CS -
Mastectomy 
and SNB and 
reconstruction 
(expander)
Cape, RT
8 32 26
T4dN2M1
IV
G2
ER/PR pos
HER2 pos
BRCA ND
AC Vaginal -  No surgery
Doce, 
trastuzumab, 
tamoxifen, RT
9 39 13
T2N1M0
IIB
G2
ER/PR pos
HER2 neg
BRCA ND
AC Vaginal - MRM Pacli, tamoxifen
10 32 30
T1cN0M0
IA
G3
ER/PR pos
HER2 neg 
BRCA pos
- CS
Induced 
delivery, 35 
weeks of 
gestation
Mastectomy 
and SNB EC, tamoxifen
11 29 6
T2N2M0
IIIA
G3
ER/PR neg
HER2 pos
BRCA neg
EC Vaginal - MRM Trastuzumab, RT
12 33 6
T1miN0M0
IA
G3
ER/PR neg
HER2 neg
BRCA neg
- Unknown - Mastectomy and SNB -
13 31 38
T3N2M0
IIIA
G3
ER/PR neg
HER2 neg
BRCA ND
- Vaginal - MRM FEC, doce, RT
14 38 36
T3N2M1
IV
G3
ER/PR pos
HER2 pos
BRCA neg
- Vaginal - No surgery
Doce, 
pertuzumab, 
trastuzumab, 
tamoxifen
AC = doxorubicin and cyclophosphamide; BC = breast cancer; BCS = breast conserving surgery; BRCA = BRCA status; Cape = capecitabine; CS = caesarean section; doce 
= docetaxel; EC = epidoxorubicin and cyclophosphamide; ER = estrogen receptor; FEC = 5-fluorourcil, epidoxorubicin and cyclophosphamide; GA = gestational age, HR = 
hormone receptor status; HER2 = HER2 status; MRM = modified radical mastectomy; ND = not done; NR = not relevant; pacli = paclitaxel; PR = progesterone receptor; RT = 
radiotherapy; SNB = sentinel lymph node biopsy
Diagnostic procedures should not significantly dif-
fer from those for non-pregnant women. Breast 
ultrasound (US) is considered the standard first 
line imaging modality with known high sensitiv-
ity, specificity and safety.22,23 Due to the increased 
density of the breast tissue mammography is less 
sensitive in this population.24 It is indicated for US 
confirmed solid lesions to determine the spread 
of calcifications, which is important for surgical 
treatment planning. By adequate shielding of the 
abdomen, mammography exposes the fetus to a 
minimal dose of radiation (0.001-0.01 mGy).25,26 
Opinions on safety of breast magnetic resonance 
imaging (MRI) in pregnant women are contradic-
tory.27 According to the latest guidelines on the use 
of contrast agents in pregnant women by European 
Radiol Oncol 2021; 55(3): 362-368.
Matos E et al./ Breast cancer during pregnancy366
Society of Urogenital Radiology breast MRI using 
gadolinium-based contrast may be done in preg-
nant woman and no extra neonatal tests are pro-
posed in these cases.28 In none of our patients MRI 
was performed during pregnancy, however, all of 
them had breast US and mammography done.
Staging investigations are not routinely indicat-
ed in newly diagnosed operable PABC, although if 
they have symptoms suggestive of distant metas-
tases, selective imaging can be performed, includ-
ing chest radiograph and an abdominal US. When 
bone metastases are suspected, MRI is currently a 
preferred diagnostic modality.26 In two of our pa-
tients primary metastatic disease was suspected at 
presentation based on elevated levels of tumour 
marker Ca 15-3 and abnormal values of ALP. In 
one patient abdominal US and lung X-ray were 
performed during pregnancy, both were normal. 
Although bone metastases were suspected due to 
reported pain in her left hip, skeletal MRI was not 
performed, since at that time it was not regarded 
as safe diagnostic procedure during pregnancy. 
However, bone scan, the standard diagnostic pro-
cedure for detection of bone metastases at that 
time, was postponed until after delivery when 
bone metastases were confirmed. In second patient 
breast cancer was diagnosed close to the end of 
pregnancy, therefore, staging of breast cancer was 
performed postpartum and included abdominal 
and thoracic CT. Liver metastases were diagnosed 
and were later on confirmed by fine needle aspira-
tion biopsy.
As in non-pregnant women a pathomorphologi-
cal characterisation of breast cancer is crucial for 
optimal decision about systemic treatment.7 Core 
needle biopsy of the tumor was performed in all 
14 patients from our series. The biology of PABC 
is considered different from that of non-pregnant 
women.8 These tumours usually present with 
more aggressive phenotype. They are frequently 
poorly differentiated, estrogen-receptor negative, 
of either triple-negative or HER2 positive sub-
type. Therefore, the disease is often diagnosed at 
higher stage.9-12 The majority of our patients had 
poorly differentiated tumours and almost half had 
a triple-negative breast cancer subtype, which is 
in concordance with other reports.7,11,12,14 As per 
guidelines genetic testing has been offered to all 
patients since it is known that the incidence of mu-
tation in BRCA 1 or 2 gene is higher in younger 
breast cancer patients and was performed in 10 pa-
tients, 4 of them were positive for germline BRCA 
mutations. In general, however, there is a lack of 
studies on this topic and its incidence in PABC is 
unknown. Beside that it is unclear how the knowl-
edge of germ line mutations in established PABC 
may affect treatment decisions, especially with re-
gard to risk-reducing operative procedures and/
or systemic treatments. On the other hand, genetic 
testing results may however affect the extent of 
breast surgery and regimen of further follow-up.7,13
Once a diagnosis of breast cancer has been 
made, it is important not to delay treatment. As 
recommended, the optimal treatment strategy for 
all of our 14 patients was planned by a multidisci-
plinary board, which consisted of surgical oncolo-
gist, medical oncologist, radiotherapist and gy-
naecologist.14 Per guidelines surgery can be safely 
performed in all three trimesters. Mastectomy and 
breast-conservation surgery are both safe, while 
breast reconstruction surgery is not recommended 
during pregnancy.7,14,24,29 The extent of axillary sur-
gery should follow the same guidelines that apply 
to the rest of the breast cancer population.14,30,31 In 
patients with clinically negative axillary lymph 
nodes, sentinel lymph node biopsy is the method 
of choice to minimize the likelihood of lymphede-
ma. Data about the safety of this procedure in preg-
nant patients are limited, but mostly show that this 
approach is safe if used in modified manner.32,33 
The safety of radioactive tracer (eg technetium 99m 
sulphur colloid) during pregnancy was verified by 
measuring the uterine dose of radiation from lym-
phoscintigraphy. Doses were found to be much 
lower than teratogenic threshold. Therefore, some 
experts believe sentinel lymph node biopsy should 
be considered standard of care in clinically nega-
tive axilla.34 On the contrary, the use of any dye is 
not permitted during pregnancy due to concern for 
maternal anaphylaxis and the possibility for tera-
togenicity.14,31,34 We found that in regard of surgery 
our patients were mostly treated in accordance to 
current clinical guidelines, but some minor devia-
tions were detected.7,14,24 In one patient blue dye was 
used to detect the sentinel lymph node. Sentinel 
node biopsy was performed in five patients, in two 
of them also breast reconstruction with expanders 
placed during the initial mastectomy. Although ac-
cording to current guidelines breast reconstruction 
surgery should not be performed during pregnan-
cy small studies support the safety of immediate 
expander placement with improved psychologic 
and aesthetic outcomes.31,32,35
The literature regarding breast radiotherapy 
during pregnancy is scarce and radiotherapy is 
according to current international guidelines con-
traindicated during pregnancy. However, some 
authors believe that modern approaches, such as 
Radiol Oncol 2021; 55(3): 362-368.
Matos E et al./ Breast cancer during pregnancy 367
3D-conformal radiotherapy (3DCRT) or intraop-
erative radiotherapy (IORT), can be considered 
during the first two trimesters in selected cases.36 
None of our patients received radiotherapy during 
pregnancy.
Eight of our patients received chemotherapy 
during pregnancy. According to guidelines sys-
temic treatment should follow the recommenda-
tions that apply to the rest of the breast cancer 
population. It should not begin before the end of 
1st trimester, upon completion of organogenesis.7,16 
Postponing treatment until after delivery may be 
associated with a worse outcome of the malignant 
disease and is therefore not advised.37,38 The dosage 
is supposed to be calculated according to the pa-
tient’s actual body weight and the intervals should 
remain the same as for non-pregnant patients.39 
Pregnancy is not a restraining factor for treatment 
with a dose-dense regimen supported by granulo-
cyte growth factors. However, more frequent blood 
counts tests are advised due to the risk of anaemia 
and neutropenia.15,40 Use of anthracyclines and 
cyclophosphamide during pregnancy was found 
to be safe, regarding the safety of other cytotoxic 
drugs during pregnancy data are scarce.41-43 Most 
of the reports on taxanes relate to the safety of pa-
clitaxel.44,45 Use of trastuzumab is contraindicated 
during pregnancy due to increased occurrence of 
oligo and anhydramnion. The same applies to oth-
er anti-HER2 therapy.15,46 Endocrine therapy is also 
not permitted during pregnancy due to many re-
ported developmental abnormalities, particularly 
with tamoxifen treatment.15,47,48
Among anti-emetics, ondansetron is classified 
as group B drug in terms of safety during preg-
nancy and metoclopramide is also recognized to 
be safe.49,50 Data regarding safety of glucocorticoids 
during pregnancy are conflicting, some favour the 
use of methylprednisolone.51
Systemic treatment of pregnant patients from 
our cohort was based on anthracyclines and did 
not start before the end of 1st trimester. One pa-
tient also received taxanes. Although some ex-
perts still warn about the routine use of taxanes in 
pregnant women, some case reports series suggest 
similar safety profiles of taxanes to doxorubicin.45 
Therefore, we do not consider this approach as 
guidelines violation. None of our patients received 
endocrine or anti-HER2 therapy during pregnancy.
In the past, PABC was thought to have a poor 
prognosis.18 Multiple less extensive, retrospective 
cohort and case-control studies conducted in re-
cent decades have demonstrated different findings. 
When adjusted for age, disease stage and morpho-
logical characteristics of the tumours many studies 
have failed to demonstrate a significantly worse 
outcome for women who were diagnosed with 
early and locally advanced breast cancer during 
pregnancy compared to non-pregnant patients.19 
On the contrary, prognosis of metastatic PABC is 
generally poor and the expected 5-year survival is 
only about 10%.
Although the median follow-up period in our 
case series is fairly short and the sample size small 
and thus is impossible to assess the impact of PABC 
on prognosis of these patients. However, no breast 
cancer relapse in initially non-metastatic patients 
was detected so far. This might suggest no signifi-
cantly worse prognosis in our series of patients.
Conclusions
Treatment of breast cancer diagnosed during preg-
nancy is a major professional and ethical challenge 
for all members of the multidisciplinary team. We 
found that the incidence of breast cancer diag-
nosed in pregnant women was low in the observed 
period. Patients were mostly treated in accordance 
with current international clinical guidelines. Only 
one event that was not in accordance was identi-
fied. It was the use of blue dye in one patient. The 
reason for this event is unknown.
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