Hormone receptor status, tumor characteristics, and prognosis:

Selected Characteristics Among Breast Cancer Cases by Hormone Receptor Status: SEER Program, 1990-2001
Characteristics	ER+PR+ (n = 98,463)			ER+PR- (n = 19,886)			ER-PR+ (n = 4,896)			ER-PR- (n = 31,930)
Characteristics	n	Column %	Row %	n	Column %	Row %	n	Column %	Row %	n	Column %	Row %
Age at diagnosis, years
30-39	4,903	5.0	49.5	885	4.5	8.9	569	11.6	5.7	3,558	11.1	35.9
40-49	18,575	18.9	60.9	2,490	12.5	8.2	1,508	30.8	4.9	7,929	24.8	26.0
50-59	21,807	22.1	61.4	4,464	22.5	12.5	1,161	23.7	3.3	8,094	25.4	22.8
60-69	22,019	22.4	65.9	4,752	23.9	14.2	801	16.4	2.4	5,856	18.3	17.5
70-79	20,667	21.0	68.2	4,662	23.4	15.4	584	11.9	1.9	4,401	13.8	14.5
≥80	10,492	10.6	67.7	2,633	13.2	17.0	273	5.6	1.8	2,092	6.6	13.5
Diagnosis year
1990-1992	16,500	16.8	61.6	3,751	18.9	14.0	1,111	22.7	4.1	5,435	17.0	20.3
1993-1995	22,087	22.4	61.7	4,514	22.7	12.6	1,485	30.3	4.1	7,728	24.2	21.6
1996-1998	27,734	28.2	64.2	5,239	26.3	12.1	1,367	27.9	3.2	8,884	27.8	20.5
1999-2001	32,142	32.6	65.2	6,382	32.1	12.9	933	19.1	1.9	9,883	31.0	20.0
SEER registry
Atlanta, GA	5,696	5.8	59.4	1,171	5.9	12.2	381	7.8	4	2,344	7.3	24.4
Connecticut	11,093	11.3	61.4	2,448	12.3	13.6	602	12.3	3.3	3,914	12.3	21.7
Detroit, MI	10,559	10.7	60.4	2,314	11.6	13.2	539	11	3.1	4,063	12.7	23.3
Hawaii	4,149	4.2	67.0	703	3.5	11.3	273	5.6	4.4	1,072	3.4	17.3
Iowa	10,238	10.4	65.2	1,914	9.6	12.2	530	10.8	3.4	3,017	9.4	19.2
Los Angeles, CA	15,586	15.8	61.4	3,399	17.1	13.4	919	18.8	3.6	5,491	17.2	21.6
New Mexico	4,066	4.1	61.8	885	4.5	13.5	193	3.9	2.9	1,435	4.5	21.8
San Francisco-Oakland, CA	13,063	13.3	63.9	2,750	13.8	13.5	652	13.3	3.2	3,957	12.4	19.4
San Jose, CA	5,474	5.5	65.3	1,134	5.7	13.5	228	4.7	2.7	1,548	4.9	18.5
Seattle, WA	14,241	14.5	68	2,517	12.7	12.0	423	8.6	2.0	3,770	11.8	18.0
Utah	4,298	4.4	66.9	651	3.3	10.1	156	3.2	2.5	1,319	4.1	20.5
Race
Non-Hispanic white	78,805	81.7	65.4	15,716	80.5	13.0	3,515	73.5	2.9	22,532	72.1	18.7
African-American	5,724	5.9	48.0	1,488	7.6	12.5	504	10.5	4.2	4,206	13.5	35.3
Native American	284	0.3	55.0	57	0.3	11.0	23	0.5	4.5	152	0.5	29.5
Asian/Pacific Islander	6,065	6.3	65.1	1,061	5.4	11.4	382	8.0	4.1	1,805	5.8	19.4
Hispanic white	5,585	5.8	57.8	1,203	6.2	12.4	359	7.5	3.7	2,524	8.1	26.1
Other/Unknown	2,000	--	--	361	--	--	113	--	--	711	--	--
Tumor histology
Ductal	71,199	72.3	62.7	13,981	70.3	12.3	3,641	74.4	3.2	24,722	77.4	21.8
Lobular	8,980	9.1	73.6	2,160	10.9	17.7	283	5.8	2.3	784	2.5	6.4
Ductal/Lobular	7,576	7.7	76.7	1,341	6.7	13.6	233	4.8	2.4	722	2.3	7.3
Inflammatory	543	0.5	37.8	191	1.0	13.3	90	1.8	6.3	611	1.9	42.6
Mucinous	2,927	3.0	80.9	486	2.4	13.5	41	0.8	1.1	164	0.5	4.5
Tubular	1,696	1.7	79	327	1.6	15.2	44	0.9	2.1	79	0.3	3.7
Comedo	1,159	1.2	43.6	318	1.6	12.0	179	3.6	6.7	1,003	3.1	37.7
Medullary	266	0.3	14.7	148	0.8	8.2	97	2.0	5.4	1,292	4.0	71.7
Papillary	582	0.6	79.0	58	0.3	7.9	10	0.2	1.3	87	0.3	11.8
Other	3,535	3.6	49.4	876	4.4	12.2	278	5.7	3.9	2,466	7.7	34.5
Tumor stage
I	50,172	52.4	69.2	9,232	48	12.7	1,999	42.7	2.8	11,114	36.2	15.3
II	37,335	39.0	60.3	7,606	39.5	12.3	2,068	44.2	3.3	14,878	48.4	24.1
III	5,332	5.5	51.3	1,471	7.6	14.1	385	8.2	3.7	3,210	10.4	30.9
IV	2,943	3.1	52.1	936	4.9	16.6	230	4.9	4.1	1,536	5.0	27.2
Unstaged	2,681	--	--	641	--	--	214	--	--	1,192	--	--
Tumor grade
1	18,012	21.8	81.1	2,885	17.5	13.0	405	9.9	1.8	914	3.3	4.1
2	40,642	49.3	74.2	7,133	43.4	13.0	1,324	32.5	2.4	5,682	20.6	10.4
3	22,082	26.8	44.4	6,027	36.6	12.1	2,174	53.3	4.4	19,412	70.4	39.1
4	1,774	2.1	45.0	413	2.5	10.5	173	4.3	4.4	1,579	5.7	40.1
Unknown	15,953	--		3,428	--		820	--		4,343	--
Tumor size (cm)
0-1.9	56,547	59.9	69.2	10,302	54.6	12.6	2,271	49.5	2.8	12,576	41.8	15.4
2-5	32,977	34.9	58.7	7,135	37.8	12.7	1,891	41.3	3.4	14,147	47.1	25.2
>5	4,949	5.2	48.8	1,432	7.6	14.1	422	9.2	4.2	3,330	11.1	32.9
Unknown	3,990	--	--	1,017	--	--	312	--	--	1,877	--	--
Axillary lymph node status
Negative	54,948	65.3	64.8	10,428	63.0	12.3	2,622	61.0	3.1	16,749	60.3	19.8
Positive	29,234	34.7	60.9	6,110	37.0	12.7	1,675	39.0	3.5	11,015	39.7	22.9
Unknown	14,281	--	--	3,348	--	--	599	--	--	4,166	--	--
Surgical treatment
Performed	96,387	98.0	63.7	19,216	96.7	12.7	4,764	97.4	3.2	30,847	96.8	20.4
Not performed	2,012	2.0	52.7	648	3.3	17.0	126	2.6	3.3	1,032	3.2	27
Unknown	64	--	--	22	--	--	6	--	--	51	--	--
Radiation therapy
Treated	46,859	48.5	65.5	8,694	44.5	12.1	2,048	42.9	2.9	13,922	44.8	19.5
None	49,776	51.5	61.9	10,836	55.5	13.4	2,725	57.1	3.4	17,131	55.2	21.3
Unknown	1,828	--	--	356	--	--	123	--	--	877	--	--

ER, estrogen receptor; PR, progesterone receptor; SEER, Surveillance, Epidemiology, and End Results.

Selected Characteristics Among Breast Cancer Cases by Hormone Receptor Status: SEER Program, 1990-2001
Characteristics	ER+PR+ (n = 98,463)			ER+PR- (n = 19,886)			ER-PR+ (n = 4,896)			ER-PR- (n = 31,930)
Characteristics	n	Column %	Row %	n	Column %	Row %	n	Column %	Row %	n	Column %	Row %
Age at diagnosis, years
30-39	4,903	5.0	49.5	885	4.5	8.9	569	11.6	5.7	3,558	11.1	35.9
40-49	18,575	18.9	60.9	2,490	12.5	8.2	1,508	30.8	4.9	7,929	24.8	26.0
50-59	21,807	22.1	61.4	4,464	22.5	12.5	1,161	23.7	3.3	8,094	25.4	22.8
60-69	22,019	22.4	65.9	4,752	23.9	14.2	801	16.4	2.4	5,856	18.3	17.5
70-79	20,667	21.0	68.2	4,662	23.4	15.4	584	11.9	1.9	4,401	13.8	14.5
≥80	10,492	10.6	67.7	2,633	13.2	17.0	273	5.6	1.8	2,092	6.6	13.5
Diagnosis year
1990-1992	16,500	16.8	61.6	3,751	18.9	14.0	1,111	22.7	4.1	5,435	17.0	20.3
1993-1995	22,087	22.4	61.7	4,514	22.7	12.6	1,485	30.3	4.1	7,728	24.2	21.6
1996-1998	27,734	28.2	64.2	5,239	26.3	12.1	1,367	27.9	3.2	8,884	27.8	20.5
1999-2001	32,142	32.6	65.2	6,382	32.1	12.9	933	19.1	1.9	9,883	31.0	20.0
SEER registry
Atlanta, GA	5,696	5.8	59.4	1,171	5.9	12.2	381	7.8	4	2,344	7.3	24.4
Connecticut	11,093	11.3	61.4	2,448	12.3	13.6	602	12.3	3.3	3,914	12.3	21.7
Detroit, MI	10,559	10.7	60.4	2,314	11.6	13.2	539	11	3.1	4,063	12.7	23.3
Hawaii	4,149	4.2	67.0	703	3.5	11.3	273	5.6	4.4	1,072	3.4	17.3
Iowa	10,238	10.4	65.2	1,914	9.6	12.2	530	10.8	3.4	3,017	9.4	19.2
Los Angeles, CA	15,586	15.8	61.4	3,399	17.1	13.4	919	18.8	3.6	5,491	17.2	21.6
New Mexico	4,066	4.1	61.8	885	4.5	13.5	193	3.9	2.9	1,435	4.5	21.8
San Francisco-Oakland, CA	13,063	13.3	63.9	2,750	13.8	13.5	652	13.3	3.2	3,957	12.4	19.4
San Jose, CA	5,474	5.5	65.3	1,134	5.7	13.5	228	4.7	2.7	1,548	4.9	18.5
Seattle, WA	14,241	14.5	68	2,517	12.7	12.0	423	8.6	2.0	3,770	11.8	18.0
Utah	4,298	4.4	66.9	651	3.3	10.1	156	3.2	2.5	1,319	4.1	20.5
Race
Non-Hispanic white	78,805	81.7	65.4	15,716	80.5	13.0	3,515	73.5	2.9	22,532	72.1	18.7
African-American	5,724	5.9	48.0	1,488	7.6	12.5	504	10.5	4.2	4,206	13.5	35.3
Native American	284	0.3	55.0	57	0.3	11.0	23	0.5	4.5	152	0.5	29.5
Asian/Pacific Islander	6,065	6.3	65.1	1,061	5.4	11.4	382	8.0	4.1	1,805	5.8	19.4
Hispanic white	5,585	5.8	57.8	1,203	6.2	12.4	359	7.5	3.7	2,524	8.1	26.1
Other/Unknown	2,000	--	--	361	--	--	113	--	--	711	--	--
Tumor histology
Ductal	71,199	72.3	62.7	13,981	70.3	12.3	3,641	74.4	3.2	24,722	77.4	21.8
Lobular	8,980	9.1	73.6	2,160	10.9	17.7	283	5.8	2.3	784	2.5	6.4
Ductal/Lobular	7,576	7.7	76.7	1,341	6.7	13.6	233	4.8	2.4	722	2.3	7.3
Inflammatory	543	0.5	37.8	191	1.0	13.3	90	1.8	6.3	611	1.9	42.6
Mucinous	2,927	3.0	80.9	486	2.4	13.5	41	0.8	1.1	164	0.5	4.5
Tubular	1,696	1.7	79	327	1.6	15.2	44	0.9	2.1	79	0.3	3.7
Comedo	1,159	1.2	43.6	318	1.6	12.0	179	3.6	6.7	1,003	3.1	37.7
Medullary	266	0.3	14.7	148	0.8	8.2	97	2.0	5.4	1,292	4.0	71.7
Papillary	582	0.6	79.0	58	0.3	7.9	10	0.2	1.3	87	0.3	11.8
Other	3,535	3.6	49.4	876	4.4	12.2	278	5.7	3.9	2,466	7.7	34.5
Tumor stage
I	50,172	52.4	69.2	9,232	48	12.7	1,999	42.7	2.8	11,114	36.2	15.3
II	37,335	39.0	60.3	7,606	39.5	12.3	2,068	44.2	3.3	14,878	48.4	24.1
III	5,332	5.5	51.3	1,471	7.6	14.1	385	8.2	3.7	3,210	10.4	30.9
IV	2,943	3.1	52.1	936	4.9	16.6	230	4.9	4.1	1,536	5.0	27.2
Unstaged	2,681	--	--	641	--	--	214	--	--	1,192	--	--
Tumor grade
1	18,012	21.8	81.1	2,885	17.5	13.0	405	9.9	1.8	914	3.3	4.1
2	40,642	49.3	74.2	7,133	43.4	13.0	1,324	32.5	2.4	5,682	20.6	10.4
3	22,082	26.8	44.4	6,027	36.6	12.1	2,174	53.3	4.4	19,412	70.4	39.1
4	1,774	2.1	45.0	413	2.5	10.5	173	4.3	4.4	1,579	5.7	40.1
Unknown	15,953	--		3,428	--		820	--		4,343	--
Tumor size (cm)
0-1.9	56,547	59.9	69.2	10,302	54.6	12.6	2,271	49.5	2.8	12,576	41.8	15.4
2-5	32,977	34.9	58.7	7,135	37.8	12.7	1,891	41.3	3.4	14,147	47.1	25.2
>5	4,949	5.2	48.8	1,432	7.6	14.1	422	9.2	4.2	3,330	11.1	32.9
Unknown	3,990	--	--	1,017	--	--	312	--	--	1,877	--	--
Axillary lymph node status
Negative	54,948	65.3	64.8	10,428	63.0	12.3	2,622	61.0	3.1	16,749	60.3	19.8
Positive	29,234	34.7	60.9	6,110	37.0	12.7	1,675	39.0	3.5	11,015	39.7	22.9
Unknown	14,281	--	--	3,348	--	--	599	--	--	4,166	--	--
Surgical treatment
Performed	96,387	98.0	63.7	19,216	96.7	12.7	4,764	97.4	3.2	30,847	96.8	20.4
Not performed	2,012	2.0	52.7	648	3.3	17.0	126	2.6	3.3	1,032	3.2	27
Unknown	64	--	--	22	--	--	6	--	--	51	--	--
Radiation therapy
Treated	46,859	48.5	65.5	8,694	44.5	12.1	2,048	42.9	2.9	13,922	44.8	19.5
None	49,776	51.5	61.9	10,836	55.5	13.4	2,725	57.1	3.4	17,131	55.2	21.3
Unknown	1,828	--	--	356	--	--	123	--	--	877	--	--

ER, estrogen receptor; PR, progesterone receptor; SEER, Surveillance, Epidemiology, and End Results.

Breast Cancer Mortality Risk by Hormone Receptor Status Among Women of Different Diagnosis Age, Race/Ethnicity, Diagnosis Year, Tumor Stage, Grade, Histology, and Axillary Lymph Node Positivity ^a
Characteristics	ER+/PR+ (n = 98,463)			ER+/PR- (n = 19,886)				ER-/PR+ (n = 4,896)				ER-/PR- (n = 31,930)				p value for interaction
Characteristics	No. at risk	No. deaths	HR	No. at risk	No. deaths	HR	95% CI	No. at risk	No. deaths	HR	95% CI	No. at risk	No. deaths	HR	95% CI	p value for interaction
All cases^b	98,463	7,319	1.0	19,886	2,434	1.4	1.3-1.5^c	4,896	848	1.8	1.6-1.9^c	31,930	6,300	2.3	2.2-2.4^c
Age at diagnosis, years^d
<50	16,962	1,042	1.0	2,387	245	1.2	1.1-1.4^c	1,430	209	1.6	1.4-1.9^c	8,056	1,323	2.1	1.9-2.3^c
50-64	23,467	1,104	1.0	4,745	416	1.5	1.3-1.7^c	1,072	124	1.5	1.2-1.8^c	7,651	1,214	2.3	2.1-2.5^c
≥65	25,078	1,496	1.0	5,563	540	1.5	1.3-1.7^c	718	119	2.1	1.8-2.6^c	5,536	1,020	2.6	2.4-2.8^c	0.03
Diagnosis year^e
1990-1992	8,298	1,285	1.0	1,889	419	1.3	1.2-1.5^c	597	146	1.6	1.3-1.9^c	2,850	831	1.7	1.5-1.9^c
1993-1995	13,665	1,348	1.0	2,688	428	1.5	1.3-1.7^c	944	160	1.5	1.2-1.8^c	4,859	1,234	2.2	2.0-2.4^c
1996-1998	19,350	837	1.0	3,493	282	1.5	1.3-1.7^c	971	121	2.1	1.7-2.6^c	6,181	1,059	2.8	2.5-3.1^c
1999-2001	24,194	172	1.0	4,625	69	1.6	1.2-2.1^c	708	25	3.6	2.3-5.1^c	7,353	433	4.9	4.1-6.0^c	<0.001
Race/Ethnicity^f
Non-Hispanicwhite	53,397	2,831	1.0	10,187	916	1.5	1.3-1.6^c	2,396	313	1.8	1.6-2.0^c	15,371	2,462	2.3	2.2-2.5^c
African-American	3,536	348	1.0	907	125	1.2	1.0-1.5^c	293	60	1.7	1.3-2.2^c	2,734	615	2.2	1.9-2.6^c
Native American	196	19	1.0	34	11	1.5	0.5-3.8	12	1	1.7	0.1-16.4	102	25	3.4	1.5-7.3^c
Asian/PacificIslander	4,497	189	1.0	748	63	1.8	1.3-2.4^c	267	34	1.6	1.1-2.4^c	1,273	166	2.3	1.8-2.8^c
Hispanic white	3,881	255	1.0	819	83	1.3	1.0-1.7^c	252	44	1.9	1.3-2.6^c	1,763	289	2.3	1.9-2.8^c	0.77
Tumor stage^g
I	33,821	487	1.0	6,038	146	1.4	1.2-1.7^c	1,369	51	1.6	1.2-2.1^c	7,704	391	2.3	2.0-2.7^c
II	27,363	2,110	1.0	5,472	674	1.4	1.3-1.6^c	1,529	248	1.6	1.4-1.9^c	11,051	2,069	2.3	2.2-2.5^c
III	3,410	659	1.0	922	252	1.3	1.2-1.6^c	245	104	2.1	1.7-2.6^c	1,940	763	2.3	2.0-2.6^c
IV	672	302	1.0	192	102	1.3	1.0-1.6^c	59	42	1.9	1.3-2.7^c	357	245	2.3	1.9-2.8^c	0.45
Tumor size (cm)^h
0-1.9	39,418	865	1.0	6,957	243	1.4	1.2-1.6^c	1,607	91	1.5	1.2-1.9^c	8,799	715	2.6	2.3-2.9^c
2-5	22,579	2,081	1.0	4,781	708	1.5	1.3-1.6^c	1,331	253	1.8	1.5-2.0^c	10,214	2,019	2.2	2.1-2.4^c
>5	2,718	526	1.0	761	206	1.3	1.1-1.6^c	217	89	2.2	1.7-2.7^c	1,730	636	2.2	1.9-2.5^c	<0.001
Axillary lymph node statusⁱ
Negative	42,451	942	1.0	7,924	324	1.6	1.4-1.8^c	1,898	114	2.0	1.6-2.4^c	12,541	1,006	2.8	2.6-3.1^c
1-3	14,953	1,021	1.0	2,828	324	1.5	1.3-1.7^c	790	133	1.8	1.5-2.1^c	4,857	977	2.5	2.3-2.7^c
4-10	5,313	861	1.0	1,133	277	1.4	1.2-1.6^c	332	108	1.7	1.3-2.1^c	2,268	793	2.4	2.2-2.7^c
≥11	2,549	734	1.0	739	249	1.2	1.0-1.4^c	182	90	1.7	1.3-2.1^c	1,386	692	2.2	1.9-2.4^c	0.08
Tumor histology^j
Ductal	52,178	2,919	1.0	9,978	994	1.5	1.4-1.6^c	2,711	390	1.8	1.6-2.0^c	18,542	3,040	2.3	2.2-2.5^c
Lobular	3,975	186	1.0	938	64	1.4	1.0-1.9^c	123	3	0.4	0.1-1.4	325	47	1.9	1.4-2.7^c
Ductal/Lobular	5,472	254	1.0	929	59	1.3	0.9-1.7	148	13	1.1	0.6-2.0	511	83	2.7	2.1-3.5^c
Inflammatory	241	52	1.0	77	22	1.4	0.8-2.3	39	19	3.4	1.9-6.1^c	258	123	3.5	2.4-5.0^c
Comedo	652	91	1.0	187	19	0.6	0.4-1.1	91	16	1.2	0.7-2.1	556	109	1.6	1.2-2.1^c
Medullary	120	14	1.0	73	6	0.7	0.2-2.2	48	4	0.9	0.2-3.0	716	54	0.7	0.4-1.4	<0.001
Tumor grade^k
1	13,854	156	1.0	2,141	40	1.6	1.1-2.3^c	310	6	1.0	0.4-2.5	661	32	2.6	1.7-3.9^c
2	32,661	1,349	1.0	5,555	374	1.5	1.3-2.1^c	1,074	95	1.7	1.3-2.1^c	4,312	575	3.1	2.8-3.4^c
3	17,352	1,873	1.0	4,613	710	1.3	1.2-1.5^c	1,694	319	1.7	1.5-1.9^c	14,967	2,635	2.1	1.9-2.2^c
4	1,399	180	1.0	315	50	1.4	1.0-2.0^c	124	25	2.1	1.4-3.3^c	1,112	226	2.3	1.8-2.8^c	<0.001

^aThe reference ER/PR profile for all analyses was ER+/PR+.
^bHRs adjusted for age and year at diagnosis, race, SEER registry, tumor histology, grade, stage, surgical and radiation treatment, and lymph node status (positive/negative).
^c p < 0.05.
^dHRs adjusted for year at diagnosis, race, SEER registry, tumor histology, grade, stage, surgical and radiation treatment, and lymph node status (positive/negative).
^eHRs adjusted for age at diagnosis, race, SEER registry, tumor histology, grade, stage, surgical and radiation treatment, and lymph node status (positive/negative).
^fHRs adjusted for age and year at diagnosis, SEER registry, tumor histology, grade, stage, surgical and radiation treatment, and lymph node status (positive/negative). Race unknown, n = 3,185.
^gHRs adjusted for age and year at diagnosis, race, SEER registry, tumor histology, grade, lymph node status (categorical), and surgical and radiation treatment. Stage unknown, n = 4,728.
^hHRs adjusted for age and year at diagnosis, race, SEER registry, tumor histology, grade, lymph node status (categorical), and surgical and radiation treatment. Size unknown, n = 7,196.
ⁱHRs adjusted for age and year at diagnosis, race, SEER registry, tumor histology, stage, grade, and surgical and radiation treatment. Nodal status unknown, n = 22,394.
^jHRs adjusted for age and year at diagnosis, race, SEER registry, tumor grade, stage, lymph node status (categorical), and surgical and radiation treatment. Other/unknown histology, n = 7,155.
^kHRs adjusted for age and year at diagnosis, race, SEER registry, tumor histology, stage, lymph node status (categorical), and surgical and radiation treatment. Grade unknown, n = 24,544.
CI, confidence interval; ER, estrogen receptor; HR, hazard ratio; PR, progesterone receptor; SEER, Surveillance, Epidemiology, and End Results.

Trends in Hazard Ratios for Breast Cancer Mortality Associated With Hormone Receptor Status and Different Demographic and Clinical Characteristics
Characteristics	ER+/PR+		ER+/PR-		ER-/PR+		ER-/PR-
Characteristics	HR	95% CI	HR	95% CI	HR	95% CI	HR	95% CI
Age at diagnosis, per 5 years^a	1.05	1.04-1.06	1.07	1.04-1.09	1.07	1.03-1.10	1.06	1.05-1.07
Diagnosis year, per year^b	0.93	0.92-0.94	0.92	0.90-0.94	0.95	0.91-0.98	0.96	0.95-0.97
Tumor stage^c	2.33	2.20-2.46	2.29	2.09-2.51	2.55	2.19-2.96	2.06	1.94-2.18
Tumor size (cm)^d	1.27	1.24-1.30	1.29	1.24-1.34	1.33	1.25-1.41	1.22	1.20-1.25
Axillary lymph node status^e	1.71	1.65-1.78	1.55	1.46-1.66	1.61	1.44-1.80	1.64	1.58-1.70
Tumor grade^f	1.62	1.55-1.70	1.49	1.36-1.63	1.72	1.46-2.03	1.24	1.16-1.32

^aFive-year categories. Reference = 30 to <35 years. HRs adjusted for year at diagnosis, race, SEER registry, tumor histology, grade, stage, surgical and radiation treatment, and lymph node status (positive/negative).
^bReference = 1990. HRs adjusted for age at diagnosis, race, SEER registry, tumor histology, grade, stage, surgical and radiation treatment, and lymph node status (positive/negative).
^cReference = stage 1. HRs adjusted for age and year at diagnosis, race, SEER registry, tumor histology, grade, lymph node status, and surgical and radiation treatment. Stage unknown, n = 4,728.
^dCategories = 0 to <1, 1 to <2, 2 to <3, 3 to <4, 4 to <5, 5 to <10, ≥10 cm. Reference = 0 to <1 cm. HRs adjusted for age and year at diagnosis, race, SEER registry, tumor histology, grade, lymph node status, and surgical and radiation treatment. Size unknown, n = 7,196.
^eCategories = 0, 1 to 3, 4 to 10, ≥11. Reference = 0. HRs adjusted for age and year at diagnosis, race, SEER registry, tumor histology, stage, grade, and surgical and radiation treatment. Nodal status unknown, n = 22,394.
^fReference = grade 1. HRs adjusted for age and year at diagnosis, race, SEER registry, tumor histology, stage, lymph node status, and surgical and radiation treatment. Grade unknown, n = 24,544.
CI, confidence interval; ER, estrogen receptor; HR, hazard ratio; PR, progesterone receptor; SEER, Surveillance, Epidemiology, and End Results.

Breast Cancer Mortality Risk by Hormone Receptor Status Among Women of Different Diagnosis Age, Race/Ethnicity, Diagnosis Year, Tumor Stage, Grade, Histology, and Axillary Lymph Node Positivity ^a
Characteristics	ER+/PR+ (n = 98,463)			ER+/PR- (n = 19,886)				ER-/PR+ (n = 4,896)				ER-/PR- (n = 31,930)				p value for interaction
Characteristics	No. at risk	No. deaths	HR	No. at risk	No. deaths	HR	95% CI	No. at risk	No. deaths	HR	95% CI	No. at risk	No. deaths	HR	95% CI	p value for interaction
All cases^b	98,463	7,319	1.0	19,886	2,434	1.4	1.3-1.5^c	4,896	848	1.8	1.6-1.9^c	31,930	6,300	2.3	2.2-2.4^c
Age at diagnosis, years^d
<50	16,962	1,042	1.0	2,387	245	1.2	1.1-1.4^c	1,430	209	1.6	1.4-1.9^c	8,056	1,323	2.1	1.9-2.3^c
50-64	23,467	1,104	1.0	4,745	416	1.5	1.3-1.7^c	1,072	124	1.5	1.2-1.8^c	7,651	1,214	2.3	2.1-2.5^c
≥65	25,078	1,496	1.0	5,563	540	1.5	1.3-1.7^c	718	119	2.1	1.8-2.6^c	5,536	1,020	2.6	2.4-2.8^c	0.03
Diagnosis year^e
1990-1992	8,298	1,285	1.0	1,889	419	1.3	1.2-1.5^c	597	146	1.6	1.3-1.9^c	2,850	831	1.7	1.5-1.9^c
1993-1995	13,665	1,348	1.0	2,688	428	1.5	1.3-1.7^c	944	160	1.5	1.2-1.8^c	4,859	1,234	2.2	2.0-2.4^c
1996-1998	19,350	837	1.0	3,493	282	1.5	1.3-1.7^c	971	121	2.1	1.7-2.6^c	6,181	1,059	2.8	2.5-3.1^c
1999-2001	24,194	172	1.0	4,625	69	1.6	1.2-2.1^c	708	25	3.6	2.3-5.1^c	7,353	433	4.9	4.1-6.0^c	<0.001
Race/Ethnicity^f
Non-Hispanicwhite	53,397	2,831	1.0	10,187	916	1.5	1.3-1.6^c	2,396	313	1.8	1.6-2.0^c	15,371	2,462	2.3	2.2-2.5^c
African-American	3,536	348	1.0	907	125	1.2	1.0-1.5^c	293	60	1.7	1.3-2.2^c	2,734	615	2.2	1.9-2.6^c
Native American	196	19	1.0	34	11	1.5	0.5-3.8	12	1	1.7	0.1-16.4	102	25	3.4	1.5-7.3^c
Asian/PacificIslander	4,497	189	1.0	748	63	1.8	1.3-2.4^c	267	34	1.6	1.1-2.4^c	1,273	166	2.3	1.8-2.8^c
Hispanic white	3,881	255	1.0	819	83	1.3	1.0-1.7^c	252	44	1.9	1.3-2.6^c	1,763	289	2.3	1.9-2.8^c	0.77
Tumor stage^g
I	33,821	487	1.0	6,038	146	1.4	1.2-1.7^c	1,369	51	1.6	1.2-2.1^c	7,704	391	2.3	2.0-2.7^c
II	27,363	2,110	1.0	5,472	674	1.4	1.3-1.6^c	1,529	248	1.6	1.4-1.9^c	11,051	2,069	2.3	2.2-2.5^c
III	3,410	659	1.0	922	252	1.3	1.2-1.6^c	245	104	2.1	1.7-2.6^c	1,940	763	2.3	2.0-2.6^c
IV	672	302	1.0	192	102	1.3	1.0-1.6^c	59	42	1.9	1.3-2.7^c	357	245	2.3	1.9-2.8^c	0.45
Tumor size (cm)^h
0-1.9	39,418	865	1.0	6,957	243	1.4	1.2-1.6^c	1,607	91	1.5	1.2-1.9^c	8,799	715	2.6	2.3-2.9^c
2-5	22,579	2,081	1.0	4,781	708	1.5	1.3-1.6^c	1,331	253	1.8	1.5-2.0^c	10,214	2,019	2.2	2.1-2.4^c
>5	2,718	526	1.0	761	206	1.3	1.1-1.6^c	217	89	2.2	1.7-2.7^c	1,730	636	2.2	1.9-2.5^c	<0.001
Axillary lymph node statusⁱ
Negative	42,451	942	1.0	7,924	324	1.6	1.4-1.8^c	1,898	114	2.0	1.6-2.4^c	12,541	1,006	2.8	2.6-3.1^c
1-3	14,953	1,021	1.0	2,828	324	1.5	1.3-1.7^c	790	133	1.8	1.5-2.1^c	4,857	977	2.5	2.3-2.7^c
4-10	5,313	861	1.0	1,133	277	1.4	1.2-1.6^c	332	108	1.7	1.3-2.1^c	2,268	793	2.4	2.2-2.7^c
≥11	2,549	734	1.0	739	249	1.2	1.0-1.4^c	182	90	1.7	1.3-2.1^c	1,386	692	2.2	1.9-2.4^c	0.08
Tumor histology^j
Ductal	52,178	2,919	1.0	9,978	994	1.5	1.4-1.6^c	2,711	390	1.8	1.6-2.0^c	18,542	3,040	2.3	2.2-2.5^c
Lobular	3,975	186	1.0	938	64	1.4	1.0-1.9^c	123	3	0.4	0.1-1.4	325	47	1.9	1.4-2.7^c
Ductal/Lobular	5,472	254	1.0	929	59	1.3	0.9-1.7	148	13	1.1	0.6-2.0	511	83	2.7	2.1-3.5^c
Inflammatory	241	52	1.0	77	22	1.4	0.8-2.3	39	19	3.4	1.9-6.1^c	258	123	3.5	2.4-5.0^c
Comedo	652	91	1.0	187	19	0.6	0.4-1.1	91	16	1.2	0.7-2.1	556	109	1.6	1.2-2.1^c
Medullary	120	14	1.0	73	6	0.7	0.2-2.2	48	4	0.9	0.2-3.0	716	54	0.7	0.4-1.4	<0.001
Tumor grade^k
1	13,854	156	1.0	2,141	40	1.6	1.1-2.3^c	310	6	1.0	0.4-2.5	661	32	2.6	1.7-3.9^c
2	32,661	1,349	1.0	5,555	374	1.5	1.3-2.1^c	1,074	95	1.7	1.3-2.1^c	4,312	575	3.1	2.8-3.4^c
3	17,352	1,873	1.0	4,613	710	1.3	1.2-1.5^c	1,694	319	1.7	1.5-1.9^c	14,967	2,635	2.1	1.9-2.2^c
4	1,399	180	1.0	315	50	1.4	1.0-2.0^c	124	25	2.1	1.4-3.3^c	1,112	226	2.3	1.8-2.8^c	<0.001

^aThe reference ER/PR profile for all analyses was ER+/PR+.
^bHRs adjusted for age and year at diagnosis, race, SEER registry, tumor histology, grade, stage, surgical and radiation treatment, and lymph node status (positive/negative).
^c p < 0.05.
^dHRs adjusted for year at diagnosis, race, SEER registry, tumor histology, grade, stage, surgical and radiation treatment, and lymph node status (positive/negative).
^eHRs adjusted for age at diagnosis, race, SEER registry, tumor histology, grade, stage, surgical and radiation treatment, and lymph node status (positive/negative).
^fHRs adjusted for age and year at diagnosis, SEER registry, tumor histology, grade, stage, surgical and radiation treatment, and lymph node status (positive/negative). Race unknown, n = 3,185.
^gHRs adjusted for age and year at diagnosis, race, SEER registry, tumor histology, grade, lymph node status (categorical), and surgical and radiation treatment. Stage unknown, n = 4,728.
^hHRs adjusted for age and year at diagnosis, race, SEER registry, tumor histology, grade, lymph node status (categorical), and surgical and radiation treatment. Size unknown, n = 7,196.
ⁱHRs adjusted for age and year at diagnosis, race, SEER registry, tumor histology, stage, grade, and surgical and radiation treatment. Nodal status unknown, n = 22,394.
^jHRs adjusted for age and year at diagnosis, race, SEER registry, tumor grade, stage, lymph node status (categorical), and surgical and radiation treatment. Other/unknown histology, n = 7,155.
^kHRs adjusted for age and year at diagnosis, race, SEER registry, tumor histology, stage, lymph node status (categorical), and surgical and radiation treatment. Grade unknown, n = 24,544.
CI, confidence interval; ER, estrogen receptor; HR, hazard ratio; PR, progesterone receptor; SEER, Surveillance, Epidemiology, and End Results.

Trends in Hazard Ratios for Breast Cancer Mortality Associated With Hormone Receptor Status and Different Demographic and Clinical Characteristics
Characteristics	ER+/PR+		ER+/PR-		ER-/PR+		ER-/PR-
Characteristics	HR	95% CI	HR	95% CI	HR	95% CI	HR	95% CI
Age at diagnosis, per 5 years^a	1.05	1.04-1.06	1.07	1.04-1.09	1.07	1.03-1.10	1.06	1.05-1.07
Diagnosis year, per year^b	0.93	0.92-0.94	0.92	0.90-0.94	0.95	0.91-0.98	0.96	0.95-0.97
Tumor stage^c	2.33	2.20-2.46	2.29	2.09-2.51	2.55	2.19-2.96	2.06	1.94-2.18
Tumor size (cm)^d	1.27	1.24-1.30	1.29	1.24-1.34	1.33	1.25-1.41	1.22	1.20-1.25
Axillary lymph node status^e	1.71	1.65-1.78	1.55	1.46-1.66	1.61	1.44-1.80	1.64	1.58-1.70
Tumor grade^f	1.62	1.55-1.70	1.49	1.36-1.63	1.72	1.46-2.03	1.24	1.16-1.32

^aFive-year categories. Reference = 30 to <35 years. HRs adjusted for year at diagnosis, race, SEER registry, tumor histology, grade, stage, surgical and radiation treatment, and lymph node status (positive/negative).
^bReference = 1990. HRs adjusted for age at diagnosis, race, SEER registry, tumor histology, grade, stage, surgical and radiation treatment, and lymph node status (positive/negative).
^cReference = stage 1. HRs adjusted for age and year at diagnosis, race, SEER registry, tumor histology, grade, lymph node status, and surgical and radiation treatment. Stage unknown, n = 4,728.
^dCategories = 0 to <1, 1 to <2, 2 to <3, 3 to <4, 4 to <5, 5 to <10, ≥10 cm. Reference = 0 to <1 cm. HRs adjusted for age and year at diagnosis, race, SEER registry, tumor histology, grade, lymph node status, and surgical and radiation treatment. Size unknown, n = 7,196.
^eCategories = 0, 1 to 3, 4 to 10, ≥11. Reference = 0. HRs adjusted for age and year at diagnosis, race, SEER registry, tumor histology, stage, grade, and surgical and radiation treatment. Nodal status unknown, n = 22,394.
^fReference = grade 1. HRs adjusted for age and year at diagnosis, race, SEER registry, tumor histology, stage, lymph node status, and surgical and radiation treatment. Grade unknown, n = 24,544.
CI, confidence interval; ER, estrogen receptor; HR, hazard ratio; PR, progesterone receptor; SEER, Surveillance, Epidemiology, and End Results.

Breast Cancer Mortality Risk by Hormone Receptor Status Among Women of Different Diagnosis Age, Race/Ethnicity, Diagnosis Year, Tumor Stage, Grade, Histology, and Axillary Lymph Node Positivity ^a
Characteristics	ER+/PR+ (n = 98,463)			ER+/PR- (n = 19,886)				ER-/PR+ (n = 4,896)				ER-/PR- (n = 31,930)				p value for interaction
Characteristics	No. at risk	No. deaths	HR	No. at risk	No. deaths	HR	95% CI	No. at risk	No. deaths	HR	95% CI	No. at risk	No. deaths	HR	95% CI	p value for interaction
All cases^b	98,463	7,319	1.0	19,886	2,434	1.4	1.3-1.5^c	4,896	848	1.8	1.6-1.9^c	31,930	6,300	2.3	2.2-2.4^c
Age at diagnosis, years^d
<50	16,962	1,042	1.0	2,387	245	1.2	1.1-1.4^c	1,430	209	1.6	1.4-1.9^c	8,056	1,323	2.1	1.9-2.3^c
50-64	23,467	1,104	1.0	4,745	416	1.5	1.3-1.7^c	1,072	124	1.5	1.2-1.8^c	7,651	1,214	2.3	2.1-2.5^c
≥65	25,078	1,496	1.0	5,563	540	1.5	1.3-1.7^c	718	119	2.1	1.8-2.6^c	5,536	1,020	2.6	2.4-2.8^c	0.03
Diagnosis year^e
1990-1992	8,298	1,285	1.0	1,889	419	1.3	1.2-1.5^c	597	146	1.6	1.3-1.9^c	2,850	831	1.7	1.5-1.9^c
1993-1995	13,665	1,348	1.0	2,688	428	1.5	1.3-1.7^c	944	160	1.5	1.2-1.8^c	4,859	1,234	2.2	2.0-2.4^c
1996-1998	19,350	837	1.0	3,493	282	1.5	1.3-1.7^c	971	121	2.1	1.7-2.6^c	6,181	1,059	2.8	2.5-3.1^c
1999-2001	24,194	172	1.0	4,625	69	1.6	1.2-2.1^c	708	25	3.6	2.3-5.1^c	7,353	433	4.9	4.1-6.0^c	<0.001
Race/Ethnicity^f
Non-Hispanicwhite	53,397	2,831	1.0	10,187	916	1.5	1.3-1.6^c	2,396	313	1.8	1.6-2.0^c	15,371	2,462	2.3	2.2-2.5^c
African-American	3,536	348	1.0	907	125	1.2	1.0-1.5^c	293	60	1.7	1.3-2.2^c	2,734	615	2.2	1.9-2.6^c
Native American	196	19	1.0	34	11	1.5	0.5-3.8	12	1	1.7	0.1-16.4	102	25	3.4	1.5-7.3^c
Asian/PacificIslander	4,497	189	1.0	748	63	1.8	1.3-2.4^c	267	34	1.6	1.1-2.4^c	1,273	166	2.3	1.8-2.8^c
Hispanic white	3,881	255	1.0	819	83	1.3	1.0-1.7^c	252	44	1.9	1.3-2.6^c	1,763	289	2.3	1.9-2.8^c	0.77
Tumor stage^g
I	33,821	487	1.0	6,038	146	1.4	1.2-1.7^c	1,369	51	1.6	1.2-2.1^c	7,704	391	2.3	2.0-2.7^c
II	27,363	2,110	1.0	5,472	674	1.4	1.3-1.6^c	1,529	248	1.6	1.4-1.9^c	11,051	2,069	2.3	2.2-2.5^c
III	3,410	659	1.0	922	252	1.3	1.2-1.6^c	245	104	2.1	1.7-2.6^c	1,940	763	2.3	2.0-2.6^c
IV	672	302	1.0	192	102	1.3	1.0-1.6^c	59	42	1.9	1.3-2.7^c	357	245	2.3	1.9-2.8^c	0.45
Tumor size (cm)^h
0-1.9	39,418	865	1.0	6,957	243	1.4	1.2-1.6^c	1,607	91	1.5	1.2-1.9^c	8,799	715	2.6	2.3-2.9^c
2-5	22,579	2,081	1.0	4,781	708	1.5	1.3-1.6^c	1,331	253	1.8	1.5-2.0^c	10,214	2,019	2.2	2.1-2.4^c
>5	2,718	526	1.0	761	206	1.3	1.1-1.6^c	217	89	2.2	1.7-2.7^c	1,730	636	2.2	1.9-2.5^c	<0.001
Axillary lymph node statusⁱ
Negative	42,451	942	1.0	7,924	324	1.6	1.4-1.8^c	1,898	114	2.0	1.6-2.4^c	12,541	1,006	2.8	2.6-3.1^c
1-3	14,953	1,021	1.0	2,828	324	1.5	1.3-1.7^c	790	133	1.8	1.5-2.1^c	4,857	977	2.5	2.3-2.7^c
4-10	5,313	861	1.0	1,133	277	1.4	1.2-1.6^c	332	108	1.7	1.3-2.1^c	2,268	793	2.4	2.2-2.7^c
≥11	2,549	734	1.0	739	249	1.2	1.0-1.4^c	182	90	1.7	1.3-2.1^c	1,386	692	2.2	1.9-2.4^c	0.08
Tumor histology^j
Ductal	52,178	2,919	1.0	9,978	994	1.5	1.4-1.6^c	2,711	390	1.8	1.6-2.0^c	18,542	3,040	2.3	2.2-2.5^c
Lobular	3,975	186	1.0	938	64	1.4	1.0-1.9^c	123	3	0.4	0.1-1.4	325	47	1.9	1.4-2.7^c
Ductal/Lobular	5,472	254	1.0	929	59	1.3	0.9-1.7	148	13	1.1	0.6-2.0	511	83	2.7	2.1-3.5^c
Inflammatory	241	52	1.0	77	22	1.4	0.8-2.3	39	19	3.4	1.9-6.1^c	258	123	3.5	2.4-5.0^c
Comedo	652	91	1.0	187	19	0.6	0.4-1.1	91	16	1.2	0.7-2.1	556	109	1.6	1.2-2.1^c
Medullary	120	14	1.0	73	6	0.7	0.2-2.2	48	4	0.9	0.2-3.0	716	54	0.7	0.4-1.4	<0.001
Tumor grade^k
1	13,854	156	1.0	2,141	40	1.6	1.1-2.3^c	310	6	1.0	0.4-2.5	661	32	2.6	1.7-3.9^c
2	32,661	1,349	1.0	5,555	374	1.5	1.3-2.1^c	1,074	95	1.7	1.3-2.1^c	4,312	575	3.1	2.8-3.4^c
3	17,352	1,873	1.0	4,613	710	1.3	1.2-1.5^c	1,694	319	1.7	1.5-1.9^c	14,967	2,635	2.1	1.9-2.2^c
4	1,399	180	1.0	315	50	1.4	1.0-2.0^c	124	25	2.1	1.4-3.3^c	1,112	226	2.3	1.8-2.8^c	<0.001

^aThe reference ER/PR profile for all analyses was ER+/PR+.
^bHRs adjusted for age and year at diagnosis, race, SEER registry, tumor histology, grade, stage, surgical and radiation treatment, and lymph node status (positive/negative).
^c p < 0.05.
^dHRs adjusted for year at diagnosis, race, SEER registry, tumor histology, grade, stage, surgical and radiation treatment, and lymph node status (positive/negative).
^eHRs adjusted for age at diagnosis, race, SEER registry, tumor histology, grade, stage, surgical and radiation treatment, and lymph node status (positive/negative).
^fHRs adjusted for age and year at diagnosis, SEER registry, tumor histology, grade, stage, surgical and radiation treatment, and lymph node status (positive/negative). Race unknown, n = 3,185.
^gHRs adjusted for age and year at diagnosis, race, SEER registry, tumor histology, grade, lymph node status (categorical), and surgical and radiation treatment. Stage unknown, n = 4,728.
^hHRs adjusted for age and year at diagnosis, race, SEER registry, tumor histology, grade, lymph node status (categorical), and surgical and radiation treatment. Size unknown, n = 7,196.
ⁱHRs adjusted for age and year at diagnosis, race, SEER registry, tumor histology, stage, grade, and surgical and radiation treatment. Nodal status unknown, n = 22,394.
^jHRs adjusted for age and year at diagnosis, race, SEER registry, tumor grade, stage, lymph node status (categorical), and surgical and radiation treatment. Other/unknown histology, n = 7,155.
^kHRs adjusted for age and year at diagnosis, race, SEER registry, tumor histology, stage, lymph node status (categorical), and surgical and radiation treatment. Grade unknown, n = 24,544.
CI, confidence interval; ER, estrogen receptor; HR, hazard ratio; PR, progesterone receptor; SEER, Surveillance, Epidemiology, and End Results.

Trends in Hazard Ratios for Breast Cancer Mortality Associated With Hormone Receptor Status and Different Demographic and Clinical Characteristics
Characteristics	ER+/PR+		ER+/PR-		ER-/PR+		ER-/PR-
Characteristics	HR	95% CI	HR	95% CI	HR	95% CI	HR	95% CI
Age at diagnosis, per 5 years^a	1.05	1.04-1.06	1.07	1.04-1.09	1.07	1.03-1.10	1.06	1.05-1.07
Diagnosis year, per year^b	0.93	0.92-0.94	0.92	0.90-0.94	0.95	0.91-0.98	0.96	0.95-0.97
Tumor stage^c	2.33	2.20-2.46	2.29	2.09-2.51	2.55	2.19-2.96	2.06	1.94-2.18
Tumor size (cm)^d	1.27	1.24-1.30	1.29	1.24-1.34	1.33	1.25-1.41	1.22	1.20-1.25
Axillary lymph node status^e	1.71	1.65-1.78	1.55	1.46-1.66	1.61	1.44-1.80	1.64	1.58-1.70
Tumor grade^f	1.62	1.55-1.70	1.49	1.36-1.63	1.72	1.46-2.03	1.24	1.16-1.32

^aFive-year categories. Reference = 30 to <35 years. HRs adjusted for year at diagnosis, race, SEER registry, tumor histology, grade, stage, surgical and radiation treatment, and lymph node status (positive/negative).
^bReference = 1990. HRs adjusted for age at diagnosis, race, SEER registry, tumor histology, grade, stage, surgical and radiation treatment, and lymph node status (positive/negative).
^cReference = stage 1. HRs adjusted for age and year at diagnosis, race, SEER registry, tumor histology, grade, lymph node status, and surgical and radiation treatment. Stage unknown, n = 4,728.
^dCategories = 0 to <1, 1 to <2, 2 to <3, 3 to <4, 4 to <5, 5 to <10, ≥10 cm. Reference = 0 to <1 cm. HRs adjusted for age and year at diagnosis, race, SEER registry, tumor histology, grade, lymph node status, and surgical and radiation treatment. Size unknown, n = 7,196.
^eCategories = 0, 1 to 3, 4 to 10, ≥11. Reference = 0. HRs adjusted for age and year at diagnosis, race, SEER registry, tumor histology, stage, grade, and surgical and radiation treatment. Nodal status unknown, n = 22,394.
^fReference = grade 1. HRs adjusted for age and year at diagnosis, race, SEER registry, tumor histology, stage, lymph node status, and surgical and radiation treatment. Grade unknown, n = 24,544.
CI, confidence interval; ER, estrogen receptor; HR, hazard ratio; PR, progesterone receptor; SEER, Surveillance, Epidemiology, and End Results.