The biological features and prognosis of breast cancer diagnosed during pregnancy: A case-control study

Figures & data

Table I. Summary of patients ’ characteristics showing matching between the two groups according to age at diagnosis, year of surgery, pT, pN and neoadjuvant chemotherapy. There were no differences observed in the type of surgery, adjuvant systemic therapy or radiotherapy.

		BCP, N (%)	Controls, N (%)	p-value
Total Number		65	130
Age (years)	<35	20 (30.8)	41 (31.5)
	35 – 39	33 (50.8)	61 (47)
	>40	12 (18.4)	28 (21.5)
	Median (range)	36 (28–47)	36 (28 – 47)	Match
Year of surgery	1996–2003	16 (24.6)	37 (28.5)
	2004–2005	20 (30.8)	36 (27.7)
	2006–2008	16 (24.6)	35 (26.9)
	2009–2010	13 (20)	22 (16.9)
	Median (range)	2005 (1996–2010)	2005 (1996–2009)	Match
pT	1	26 (40)	52 (40)
	2	31 (47.7)	62 (47.7)
	3	6 (9.2)	12 (9.2)
	X	2 (3.1)	4 (3.1)	Match
pN	0	28 (43.1)	56 (43.1)
	1	19 (29.2)	38 (29.2)
	2	10 (15.4)	20 (15.4)
	3	6 (9.2)	12 (9.2)
	X	2 (3.1)	4 (3.1)	Match
Neoadjuvant chemotherapy	Yes	7 (10.8)	14 (10.8)
	No	58 (89.2)	116 (89.2)	Match
Adjuvant chemotherapy	Yes	44 (67.7)	81 (62.3)
	No	21 (32.3)	49 (37.7)	0.460
Type of chemotherapy	CMF	5 (7.7)	14 (10.8)
	Anthracycline-based	38 (58.5)	62 (47.7)
	Anthracycline-taxane	1 (1.5)	3 (2.3)
	Other	0 (0)	2 (1.5)
	No	21 (32.3)	49 (37.7)	0.657
Surgery	Quadrantectomy	42 (64.6)	80 (61.5)
	Mastectomy	23 (35.4)	50 (38.5)	0.676
Adjuvant	Yes	46 (70.8)	101 (77.7)
hormonal	No	19 (29.2)	29 (22.3)	0.290
therapy
Adjuvant	Yes	51 (78.5)	109 (83.9)
radiotherapy	No	14 (21.5)	21 (16.1)	0.154

BCP, breast cancer during pregnancy; CMF, cyclophosphamide, methotrexate, 5-florouracil; pN, pathological nodal status; pT, pathological tumor size.

Figure 1. The distribution of breast cancer (BC) subtypes in patients diagnosed with breast cancer during pregnancy (BCP) and matched BC controls. No differences were observed (p50.676).

Table II. Pathological features of patients with breast cancer during pregnancy (BCP) and matched breast cancer (BC) controls. No significant differences between the two groups were observed.

		BCP, N (%)	Controls, N (%)	p-value
Total Number		65	130
Pathological subtype	Ductal	58 (89.2)	116 (89.2)
	Lobular	0 (0)	5 (3.9)
	Others	7 (10.8)	9 (6.9)	0.171
Histological grade	1	4 (6.2)	4 (3.1)
	2	21 (32.3)	43 (33.1)
	3	36 (55.3)	68 (52.3)
	NA*	4 (6.2)	15 (11.5)	0.604
PVI	Absent	31 (47.7)	74 (56.9)
	Focal*	20 (30.8)	32 (24.6)
	Extensive***	14 (21.5)	24 (18.5)	0.223
ER	Positive	43 (66.1)	96 (73.8)
	Negative	22 (33.9)	34 (26.2)	0.263
PR	Positive	42 (64.6)	85 (65.4)
	Negative	23 (35.4)	45 (34.6)	0.915
HER2	Positive	11 (16.9)	23 (17.7)
	Negative	54 (83.1)	107 (82.3)	0.792
Ki-67 (median value)	<30%	30 (46.1)	62 (47.7)
	>30%	35 (53.9)	68 (52.3)	0.342

BC, breast cancer; BCP, breast cancer during pregnancy; ER, estrogen receptor; PR, progesterone receptor; PVI, peri-tumoral vascular invasion.

*NA: not assessable (diagnosis on lymph nodes or after neoadjuvant chemotherapy); ** Focal: one tumor embolus in only one block; *** Extensive: more than 1 tumor embolus in more than 1 block;

Table III. Differences in events between patients with breast cancer during pregnancy (BCP) and matched breast cancer (BC) controls. More distant relapses were observed in the BCP group.

Description of events	BCP (n = 65) N (%)	BC controls (n= 130) N (%)
Local recurrence	3 (4.6)	6 (4.6)
Regional recurrence	0 (0)	2 (1.5)
Simultaneous loco-regional recurrence	1 (1.5)	1 (0.8)
Distant recurrence	15 (23.1)	18 (13.8)
Contralateral breast cancer	2 (3.1)	1 (0.8)
Other non-breast primary tumor	1 (1.5)	1 (0.8)
Total deaths	11 (16.9)	15 (11.5)

Figure 2. Differences in DFS and OS between patients with breast cancer during pregnancy (BCP) and matched breast cancer (BC) controls. A. disease-free survival, B. overall survival.

Figure 3. Differences in DFS and OS between patients with breast cancer during pregnancy (BCP) and matched breast cancer (BC) controls after exclusion of patients who received neoadjuvant chemotherapy. A. disease-free survival, B. overall survival.

Figure 4. Differences in DFS and OS in patients with breast cancer during pregnancy (BCP) according to method of pregnancy termination. A. disease-free survival, B. overall survival.