Forty years of landmark trials undertaken by the Danish Breast Cancer Cooperative Group (DBCG) nationwide or in international collaboration

Figures & data

Table 1. Loco-regional treatment, 10-year loco-regional recurrence, disease-free and overall survival.

Study	Regimens	N	LRR (%)	DFS; 95% CI	OS; 95% CI
DBCG 82B	Mastectomy + RT	852	9	48% (45; 52)	54% (51; 58)
Overgaard [10]	Mastectomy	856	32	34% (30; 37)	45% (42; 48)
DBCG 82C	Mastectomy + RT	686	8	36% (32; 40)	45% (41; 49)
Overgaard [11]	Mastectomy	689	35	24% (21; 28)	36% (33; 40)
DBCG 82TM	Lumpectomy + RT	381	7	60% (55; 64)	73% (68; 77)
Blichert-Toft [17]	Mastectomy	350	11	61% (56; 66)	71% (66; 76)
DBCG IMN	IMN + RT	1492	^#2.2	#27% (25;30)	#76% (74; 78)
Thorsen [31]	IMN (no RT)	1597	^#2.6	#30% (27;32)	#72% (70; 75)

LRR: loco-regional recurrence; DFS: disease-free survival; OS: overall survival; CI: confidence interval; RT: radiotherapy.

^# DFS and OS at eight years follow-up.

Table 2. Adjuvant endocrine treatment.

Study	Regimens	N	DFS HR; 95% CI	OS HR; 95% CI
CBC 02	Tamoxifen two years	164	0.74; 0.53–1.05^a	0.79; 0.63–0.99
Jensen [51]	Placebo	153
DBCG 77C	Tamoxifen one year	868	0.87; 0.77–0.98	0.83; 0.73–0.94^b
Knoop [52]	Control	848
DBCG 82B	CMF + Tamoxifen	320	0.93; 0.76–1.15	1.05; 0.85–1.30
Andersson [56]	CMF	314
DBCG 89C	Tamoxifen one year	554
Andersen [54]	Tamoxifen two years	535	1.04; 0.89–1.22	0.99; 0.85–1.15
	TAM→Megace	526	1.11; 0.94–1.30	1.05; 0.90–1.23
IES	Tamoxifen	615
Bliss [73]	Exemestane	584	0.84; 0.71–0.99	0.79; 0.66–0.94
BIG 1–98	Tamoxifen	2459
Regan [71]	Letrozole	2463	0.86; 0.78–0.96	0.87; 0.77–0.999
	TAM→Letrozole^c	1548	1.07; 0.92–1.25	1.10; 0.90–1.33
	Letrozole→TAM^c	1540	1.06; 0.91–1.23	0.97; 0.80–1.19
FACE	Anastrozole	2075	0.93; 0.80–1.07	0.98; 0.82–1.17
Smith [76]	Letrozole	2061
SOLE	Cont. letrozole	2441
Colleoni [78]	With breaks	2443	1.08; 0.93–1.26	0.85; 0.68–1.07

DFS: disease-free survival; OS: overall survival; CI: confidence interval; HR: hazard ratio.

^a Breast cancer recurrence.

^b Breast cancer mortality.

^c Versus five years of letrozole; TAM: tamoxifen.

Table 3. Adjuvant HER2 targeted treatment.

Study	Regimens	N	DFS HR; 95% CI	OS HR; 95% CI
HERA	Trastuzumab two years	1700	0.77; 0.69-0.87	NA
Cameron [83]	Trastuzumab one year	1702	0.76; 0.68–0.86	0.74; 0.64–0.86
	Control	1697
ALTTO	Lapatinib + T	2093	0.84; 0.70–1.02	0.80; 0.62–1.03
Piccart [84]	T→lapatinib	2091	0.96; 0.80–1.15	0.91; 0.71–1.16
	Lapatinib	2100	1.34; 1.13–1.60	1.36; 1.09–1.72
	Trastuzumab	2097
APHINITY	Pertuzumab	2400	0.81; 0.66–1.00	0.89; 0.66–1.21
Minckwitz [85]	Control	2404
ExteNet	Neratinib one year	1420	0.67; 0.50–0.91	NA
Chan [86]	Control	1420

DFS: disease-free survival; OS: overall survival; HR: hazard ratio; CI: confidence interval; T: trastuzumab; NA: non-available.

Table 4. Adjuvant chemotherapy.

Study	Regimens	N	DFSHR; 95% CI	OSHR; 95% CI
DBCG 77B	Ctx	181	0.62; 0.46–0.83	0.70; 0.52–0.95
Ejlertsen [89]	Oral CMF	193	0.70; 0.53–0.93	0.70; 0.52–0.94
	Control	187
DBCG 77B	Ctx	424	0.95; 0.77–1.16	1.09; 0.92–1.29
Ejlertsen [89]	Oral CMF	423
DBCG 82C	TAM + CMF	709	0.82; 0.71–0.93	0.95; 0.85–1.08
Ejlertsen [78]	TAM	736
DBCG 89D	CEF	615	0.84; 0.71–0.99	0.79; 0.66–0.94
Ejlertsen [95]	CMF	584
DBCG READ	EC→D	1001	1.00; 0.78–1.28	1.15; 0.83–1.59
Ejlertsen [101]	DC	1011
BIG 2–98	4A→3CMF	481	0.81; 0.67–0.99	0.85; 0.67–1.11
Oakman [103]	3A→3D→4CMF	960	1.02; 0.84–1.23	0.96; 0.76–1.21
	4AC→4CMF	487
	4AD→4CMF	959

DFS: disease-free survival; OS: overall survival; HR: hazard ratio; CI: confidence interval; Ctx: oral cyclophosphamide; C: cyclophosphamide; F: fluorouracil; M: methotrexate; A: doxorubicin; E: epirubicin; D: docetaxel TAM: tamoxifen.

Figure 1. Overall survival (OS) according to period of diagnosis. All patients, irrespective of adjuvant treatment.

Figure 2. Patients and treatments in successive decades.

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