Table 3.

Exposure-adjusted incidence rate per 100 patient years for long-term morbidity by group of surgery

	Breast conserving surgery (n = 283)
	CBCS (n = 95), exposure (d) = 94,048			OBCS (n = 188), exposure (d) = 126,068
	patients with events, n (%)	number of events	rate per 100 PYs	patients with events, n (%)	number of events	rate per 100 PYs	p value
Long-term morbidity	25 (26.3)	29	11.3	56 (29.8)	88	25.5	<0.001
Atrophy	0 (0.0)	0	0.0	1 (0.5)	1	0.3	1.000
Axillary web syndrome	0 (0.0)	0	0.0	3 (1.6)	4	1.2	0.141
Chronic pain	15 (15.8)	17	6.6	40 (21.3)	46	13.3	0.011
Fat necrosis	1 (1.1)	1	0.4	2 (1.1)	4	1.2	0.401
Fibrosis	0 (0.0)	0	0.0	4 (2.1)	4	1.2	0.141
Impairment of shoulder mobility	9 (9.5)	9	3.5	10 (5.3)	11	3.2	0.826
Lymphedema	1 (1.1)	1	0.4	11 (5.9)	14	4.1	0.003
Relevant seromaa	1 (1.1)	1	0.4	4 (2.1)	4	1.2	0.401
	Mastectomy (n = 153)
	CM (n = 52), exposure (d) = 44,421			NSM/SSM (n = 101), exposure (d) = 78,605
	patients with events, n (%)	number of events	rate per 100 PYs	patients with events, n (%)	number of events	rate per 100 PYs	p value
Long-term morbidity	18 (34.6)	36	29.6	37 (36.6)	60	27.9	0.832
Abdominal hernia	0 (0.0)	0	0.0	1 (1.0)	1	0.5	1.000
Atrophy	0 (0.0)	0	0.0	1 (1.0)	1	0.5	1.000
Axillary web syndrome	1 (1.9)	2	1.6	6 (5.9)	6	2.8	0.719
Chronic pain	7 (13.5)	10	8.2	23 (22.8)	25	11.6	0.385
Fat necrosis	0 (0.0)	0	0.0	2 (2.0)	2	0.9	0.539
Fibrosis	0 (0.0)	0	0.0	1 (1.0)	1	0.5	1.000
Impairment of shoulder mobility	7 (13.5)	8	6.6	14 (13.9)	15	7.0	1.000
Lymphedema	7 (13.5)	9	7.4	5 (5.0)	6	2.8	0.063
Relaxatio	0 (0.0)	0	0.0	1 (1.0)	2	0.9	0.539
Relevant seromaa	6 (11.5)	7	5.8	1 (1.0)	1	0.5	0.004

^aSeroma or hematoma requiring intervention and/or causing discomfort.