Intrinsic subtypes and benefit from postmastectomy radiotherapy in node-positive premenopausal breast cancer patients who received adjuvant chemotherapy – results from two independent randomized trials

Figures & data

Table 1. Distribution of patient and clinicopathological parameters among patients from the BC and DBCG 82b study cohorts.

	BC trial							DBCG 82b trial
	All	(%)	RT	(%)	NoRT	(%)	p value	All	(%)	RT	(%)	NoRT	(%)	p value
Patients (N)	145	(100%)	69	(48%)	76	(52%)		83	(100%)	45	(54%)	38	(46%)
Ovarian ablation	35	(24%)	19	(28%)	16	(21%)	.36	0	(0%)	0	(0%)	0	(0%)
Age							.58							.94
<41	41	(28%)	18	(26%)	23	(30%)		15	(18%)	8	(18%)	7	(18%)
41-	104	(72%)	51	(74%)	53	(70%)		68	(82%)	37	(82%)	31	(82%)
Tumor size (mm)							.65							.64
<21	40	(28%)	16	(23%)	24	(32%)		24	(29%)	12	(27%)	12	(32%)
21–50	82	(57%)	41	(59%)	41	(54%)		46	(55%)	27	(60%)	19	(50%)
>50	9	(6%)	4	(6%)	5	(7%)		13	(16%)	6	(13%)	7	(18%)
Unknown	14	(10%)	8	(12%)	6	(8%)		0	(0%)	0	(0%)	0	(0%)
Lymph node status							.80							.44
1–3 positive	84	(58%)	38	(55%)	46	(61%)		42	(51%)	21	(47%)	21	(55%)
>3 positive	49	(34%)	25	(36%)	24	(32%)		41	(49%)	24	(53%)	17	(45%)
Unknown	12	(8%)	6	(9%)	6	(8%)		0	(0%)	0	(0%)	0	(0%)
Malignancy grade							.53							.78
Grade 1	16	(11%)	7	(10%)	9	(12%)		10	(12%)	4	(9%)	6	(16%)
Grade 2	51	(35%)	25	(36%)	26	(34%)		47	(57%)	26	(58%)	21	(55%)
Grade 3	55	(38%)	29	(42%)	26	(34%)		23	(28%)	13	(29%)	10	(26%)
Unknown	23	(16%)	8	(12%)	15	(20%)		3	(4%)	2	(4%)	1	(3%)
Histopathology
Ductal carcinoma	131	(90%)	63	(91%)	68	(89%)	.71	70	(84%)	39	(87%)	31	(82%)	.52
ER-pos	79	(54%)	38	(55%)	41	(54%)	.89	55	(66%)	31	(69%)	24	(63%)	.58
HER2-pos	22	(15%)	14	(20%)	8	(11%)	.10	26	(31%)	13	(29%)	13	(34%)	.60
Intrinsic subtype							.17							.77
LumA	56	(39%)	26	(38%)	30	(39%)		30	(36%)	18	(40%)	12	(32%)
LumB	23	(16%)	10	(14%)	13	(17%)		15	(18%)	6	(13%)	9	(24%)
Her2-E	25	(17%)	17	(25%)	8	(11%)		12	(14%)	7	(16%)	5	(13%)
Basal-like	27	(19%)	12	(17%)	15	(20%)		16	(19%)	9	(20%)	7	(18%)
Normal-like	14	(10%)	4	(6%)	10	(13%)		10	(12%)	5	(11%)	5	(13%)

Figure 1. Loco-regional recurrence as a function of randomization assignment to adjuvant postmastectomy radiotherapy (RT) within the study cohorts of the BC-trial (left) and the DBCG 82b-trial (right).

Figure 2. Loco-regional recurrence among patients with a Luminal A tumor as a function of randomization to adjuvant postmastectomy radiotherapy (RT) within the BC-trial (left) and the DBCG 82b-trial (right).

Figure 3. Forest plot showing the association between radiotherapy (RT) and the incidence of local-regional recurrence within different intrinsic subtype subgroups. BC-trial (Blue bar), DBCG 82b-trial (Red bar) and Merged data (Black bar). In subgroups with no events, HR cannot be estimated, nor can the overall HR.