Long-term mortality in a cohort study of 6 800 French breast cancer patients treated between 1954 and 1983

Figures & data

Table I.  Initial characteristics of 6 800 breast cancer patients.

Mean age at diagnosis (Min-Max)	56 (21–94)
Period of diagnosis	Number of patients (%)
1954–1956	378 (6)
1957–1976	3 833 (56)
1977–1983	2 589 (38)
Clinical features of the breast tumour
T UICC
0,1	1 176 (17)
2	2 944 (43)
3	1 348 (20)
4*	1 332 (20)
N UICC
0	2 356 (35)
1	3 459 (51)
2	621 (9)
3	364 (5)
M UICC
0	6 206 (91)
1	594 (09)
Laterality^†
Right-sided	3 029 (45)
Left-sided	3 249 (48)
Site of the tumour^‡
External + Medial	5 616 (83)
Internal	1 184 (17)
First treatment of breast cancer: Number of patients (%)
Conservative surgery with radiotherapy	864 (13)
Mastectomy alone	1 692 (25)
Mastectomy before radiotherapy	1 617 (24)
Mastectomy after radiotherapy	978 (14)
Radiotherapy alone	1 452 (21)
No loco-regional treatment	197 (3)
Follow-up
Median follow-up	10 (1–48)
Number of patients lost to follow-up (%)	94 (1.4)
Number of dead patients (%)	5 436 (80)

*Including 674 inflammatory breast cancer.

^†110 patients had a bilateral breast cancer and for 412 laterality was not known.

^‡External tumour: Includes tumours in the upper-outer quadrant of the breast, tumours in the lower-outer quadrant of the breast and axillary tail of the breast; Medial Tumour: Includes tumours in the nipple (areola) and the central portion of the breast; Internal Tumour: Includes tumours in the upper-inner quadrant of the breast and lower-inner quadrant of the breast.

Table II.  Standardized mortality rate (SMR) among 6 800 women according to clinical parameters and radiotherapy.

	O/E	PYR	SMR	95% CI	p	AER (%)	95% CI
Total cohort	5 436/1 724	82 039	3.15	3.07–3.24	–	4.6	4.4–4.8
Age
≤ 40	498/40	10 863	12.4	11.4–13.6		4.3	4.0–4.8
41–50	1 164/227	27 517	5.1	4.8–5.4	<0.0001*	3.6	3.3–3.8
> 50	3 774/1 457	43 659	2.6	2.5–2.7		5.5	5.3–5.8
Period
1954–1956	363/97	3 485	3.7	3.4–4.1		8.0	7.0–9.1
1957–1976	3 344/1 066	45 287	3.1	3.0–3.2	<0.01	5.2	4.9–5.4
1976–1983	1 729/560	33 267	3.1	2.9–3.2		3.5	3.3–3.8
Stage
0, I	367/205	13 191	1.8	1.6–2.0		1.3	1.1–1.6
II	2 563/1 110	50 202	2.3	2.2–2.4	<0.0001	3.0	2.8–3.2
III and IV	2 506/409	18 646	6.1	5.9–6.4		11.3	10.8–11.8
Laterality
Left	2 599/838	39 598	3.1	2.9–3.2		4.5	4.2–4.7
Right	2 376/763	37 137	3.1	2.9–3.2	0.92	4.4	4.2–4.7
Location
External + Medial	4 498/1 382	66 287	3.3	3.2–3.4		4.8	4.6–4.9
Internal	938/341	15 751	2.7	2.6–2.9	<0.0001	3.9	3.5–4.2
Radiotherapy
No	1 389/746	29 154	1.9	1.8–2.0		2.4	2.2–2.6
Yes	4 047/978	52 885	4.1	4.0–4.3	<0.0001	5.8	5.5–5.9

O: Observed cases.

E: Expected cases.

PYR: Number of person-years at risk.

SMR: standardised mortality rate (Ratio of observed to expected cases during the follow-up).

CI: confidence interval.

EAR: excess Absolute risk per 100 PY of follow-up.

*p: p for trend.

Figure 1.  Ratio of observed to expected deaths (left panel) and Excess absolute risk (right panel) between 0 and 40 years after a primary breast cancer (n = 6800).

Table III.  Total number of observed and expected deaths, SMR and EAR according to age at diagnosis and follow-up (N = 6 800).

	≤40 years (n = 751)						41–50 years (n = 1 754)						>50 years (n = 4 295)
Years of follow-up	O/E	PYR	SMR	95% CI	EAR (%)	95% CI	O/E	PYR	SMR	95% CI	EAR (%)	95% CI	O/E	PYR	SMR	95% CI	EAR (%)	95% CI
0–5	278/4	2 964	65.7	58.4–73.8	9.2	8.2–10.4	542/23	7 280	23.2	21.3–25.2	7.1	6.5–7.8	1 804/355	16 225	5.1	4.8–5.3	8.8	8.3–9.3
6–10	96/4	2 083	23.2	18.9–28.2	4.4	3.5–5.4	211/23	5 483	9.1	7.9–10.4	3.4	2.9–4.0	765/284	10 266	2.7	2.5–2.9	4.7	4.2–5.2
11–15	48/5	1 740	10.0	7.4–13.1	2.5	1.8–3.4	127/26	4 657	4.9	4.1–5.8	2.1	1.7–2.6	437/258	7 275	1.7	1.5–1.9	2.6	2.1–3.1
16–20	30/6	1 558	5.3	3.6–7.5	1.6	0.9–2.3	84/31	4 135	2.7	2.2–3.3	1.2	0.8–1.7	348/242	5 321	1.4	1.3–1.6	1.9	1.3–2.5
21–25	17/6	1 156	3.0	1.8–4.7	0.9	0.4–1.8	69/33	2 957	2.1	1.6–2.6	1.2	0.7–1.8	221/177	2 966	1.3	1.1–1.4	1.5	0.7–2.4
26–30	9/5	692	1.8	0.8–3.1	0.6	−0.03–1.6	51/31	1 644	1.7	1.3–2.2	1.3	0.5–2.2	129/91	1 134	1.4	1.2–1.7	2.6	0.9–4.5
31–35	8/5	392	1.7	0.8–3.2	0.9	−0.2–2.6	31/27	858	1.2	0.8–1.6	0.5	−0.6–1.8	47/37	368	1.3	0.9–1.7	2.8	−0.3–6.6
>35	12/6	277	2.0	1.1–3.4	2.2	0.2–5.1	49/32	503	1.5	1.1–2.0	2.9	0.6–5.8	23/15	104	1.6	1.0–2.3	8.0	0.3–18.2

O: Observed cases.

E: Expected cases.

SMR: standardised mortality rate (Ratio of observed to expected cases during the follow-up).

CI: confidence interval.

EAR: Excess Absolute Risk per 100 PY of follow-up.

Table IV.  Total number of observed and expected deaths SMR and EAR according to follow-up and the period of initial treatment of breast cancer (N = 6 800).

	1954–1956 (n = 378)						1957–1976 (n = 3 833)						1977–1983 (n = 2 589)
years of follow-up	O/E	PYR	SMR	95% CI	EAR (%)	95% CI	O/E	PYR	SMR	95% CI	EAR (%)	95% CI	O/E	PYR	SMR	95% CI	EAR (%)	95% CI
0–5	204/20	1 251	10.2	8.8–11.6	10.6	8.7–12.5	1 681/221	14 165	7.6	7.2–7.9	10.2	9.6–10.8	739/142	11 054	5.2	4.8–5.6	5.4	4.9–5.8
6–10	51/15	701	3.5	2.6–4.5	3.4	1.7–5.0	593/171	9 084	3.5	3.2–3.8	4.5	4.1–5.1	428/126	8 048	3.4	3.1–3.7	3.7	3.3–4.2
11–15	27/15	504	1.8	1.2–2.5	2.1	0.4–3.9	338/156	6 798	2.2	1.9–2.4	2.7	2.2–3.2	247/119	6 371	2.1	1.8–2.4	2.1	1.6–2.5
16–20	30/15	367	2.0	1.4–2.8	2.5	0.2–4.7	219/152	5 426	1.4	1.3–1.6	1.4	0.9–1.8	213/112	5 221	1.9	1.7–2.2	1.6	1.1–2.0
21–25	14/10	251	1.4	0.8–2.3	1.1	−1.1–3.4	195/147	4 395	1.3	1.2–1.5	1.1	0.6–1.5	98/59	2 433	1.7	1.4–2.0	1.5	0.8–2.2
26–30	18/7	170	2.4	1.5–3.7	2.1	−1.2–5.6	167/115	3 160	1.5	1.3–1.6	1.2	0.6–1.8	4/4	141	1.0	0.4–2.6	−0.07	−1.8–1.7
31–35	2/6	117	0.3	0.05–1.0	−0.9	−0.9–1.0	84/62	1 501	1.3	1.1–1.7	1.1	0.1–2.0	0	–	–	–	–	–
>35	17/8	124	2.0	1.2–3.2	3.1	−1.9–7.9	67/44	759	1.5	1.2–1.9	2.5	0.7–4.4	0	–	–	–	–	–

O: Observed cases.

E: Expected cases.

SMR: standardised mortality rate (Ratio of observed to expected cases during the follow-up).

CI: confidence interval.

EAR: Excess Absolute Risk per 100 PY of follow-up.

Table V.  Total number of observed and expected deaths SMR and EAR according to follow-up with regard to radiotherapy as part of the initial treatment (N = 6 800).

	Women not treated with radiotherapy (n = 1 887)						Women treated with radiotherapy (n = 4 913)
Years of follow-up	O/E	PYR	SMR	95% CI	EAR (%)	95% CI	O/E	PYR	SMR	95% CI	EAR (%)	95% CI
0–5	494/139	8 038	3.5	3.2–3.9	4.4	3.9–4.9	2 130/243	1 8431	8.8	8.4–9.1	10.1	9.6–10.6
6–10	266/128	6 212	2.1	1.8–2.3	2.3	1.9–2.8	806/183	1 1621	4.4	4.1–4.7	5.2	4.7–5.6
11–15	200/124	5 026	1.6	1.4–1.8	1.8	1.3–2.3	412/165	8 647	2.5	2.3–2.7	2.7	2.3–3.2
16–20	164/118	4 092	1.4	1.2–1.6	1.0	0.6–1.5	298/161	6 922	1.9	1.7–2.1	1.8	1.4–2.2
21–25	111/104	2 936	1.1	0.9–1.3	0.3	−0.2–0.8	196/111	4 143	1.8	1.6–2.0	1.8	1.3–2.4
26–30	83/69	1 636	1.2	1.0–1.5	0.7	0.06–1.6	106/58	1 834	1.8	1.5–2.2	1.7	0.8–2.7
31–35	36/38	807	0.9	0.7–1.3	−0.2	−1.1–1.0	50/30	811	1.7	1.2–2.2	1.9	0.6–3.6
>35	35/26	407	1.4	1.0–1.9	2.1	0.04–4.9	49/27	475	1.8	1.4–2.4	3.5	1.2–6.4

O: Observed cases.

E: Expected cases.

PYR: Number of person-years at risk.

SMR: standardised mortality rate (Ratio of observed to expected cases during the follow-up).

CI: confidence interval.

EAR: Excess absolute risk per 100 PY of follow-up.

Table VI.  Relative risk and adjusted relative risk among 6 800 women according to clinical parameters and radiotherapy.

	O/E	RR	95% CI	p	RR*	95% CI	p
Age
≤ 40	498/40	1 (Ref)	–		1 (Ref)	–
41–50	1 164/227	0.4	0.4–0.5	<0.0001^†	0.4	0.4–0.5	<0.0001
> 50	3 774/1 457	0.2	0.2–0.3		0.2	0.2–0.3
Period
1954–1956	363/97	1 (Ref)	–		1 (Ref)	–
1957–1976	3 344/1 066	0.8	0.7–0.9	<0.01	0.8	0.7–0.9	<0.0001
1977–1983	1 729/560	0.8	0.7–0.9		1.0	0.9–1.1
Stage
0, I	367/205	1 (Ref)	–		1 (Ref)	–
II	2 563/1 110	1.3	1.2–1.4	<0.0001^†	1.5	1.3–1.7	<0.0001
III and IV	2 506/409	3.4	3.1–3.8		3.5	3.1–3.9
Radiotherapy
No	1 389/746	1 (Ref)	–		1 (Ref)	–	<0.0001
Yes	4 047/978	2.2	2.1–2.4	<0.0001	1.7	1.6–1.8

O: Observed cases.

E: Expected cases.

PYR: Number of person-years at risk.

CI: confidence interval.

RR: relative risk.

*Multivariate analysis: Adjusted RR for other factors. Each risk estimate is adjusted to all other risk factors shown in the table.

^†p: p for trend.

Table VII.  Studies of long-term mortality after breast cancer compared with expected survival for the general population with the same age distribution

Authors	Period of diagnosis	Number of patients	Follow-up (years)	Method	Comments on late mortality
Adair et al. 1974 (USA)	1940–1943	1 458	30	Relative survival (corrected for other causes of death)	Survivors after 20-years are considered cured
Duncan et al. 1976 (Edinburgh, Scotland)	1943–1953	982	>20	Age corrected survival	Excess overall mortality up to 10 years Excess mortality from breast cancer up to 20 years
Langlands et al. 1979 (Edinburgh, Scotland)	1954–1964	3 878	20	SMR, EAR	SMR > 1 at 17–20 years
Ferguson et al. 1982 (USA)	1927–1978	1 259	30	Relative survival	Observed curve approximately parallel to the expected survival curve in the neighbourhood of 15–20 years
Hibberd et al. 1983 (New Zeland)	1950–1954	2 019	30	Relative survival	Relative survival flatten out after 20 years Excess mortality from breast cancer up to 20 years
Brinkley et al. 1984 (Cambridge area, UK)	1947–1950	704	35	SMR	SMR > 1 at 30–35 years
Lê MG et al. 1984 (France)	1954–1967	2 151	>25	SMR	SMR > 1 at 25–30 years
Rutqvist et al. 1984 (Norway)	1953–1967	14 731	18	Relative survival	Excess overall mortality up to 18 years
Al Fouadi et al. 1987 (Birmingham, UK)	1936–1950	4 703	>35	SMR , EAR	O/E > 1 after 29 years (not statistically different from 1)
Brenner et al. 2004 (Finland)	1953–1999	18 578	40	Relative survival	Excess mortality throughout at least 40 years
Hooning et al. 2006 (Netherlands)	1970–1986	7 425	>25	SMR, EAR	Excess mortality from breast cancer up to 25 years

SMR (Standardised Mortality Rate): Ratio of observed to expected cases during the follow-up.

EAR (Excess Absolute Risk): Difference between the observed and expected deaths divided by the number of person-years of follow-up.