Table 3

A comparison between the LR⁺RT⁺and LR^-RT⁺/LR^-RT^-subgroups
Factor	LR⁺RT⁺	LR^-RT⁺/LR^-RT^-	P value

ER status, number
Negative	10	11
Positive	9	69	0.0007^a
Median age, years
All	48	61	0.00004^b
ER^-subgroup	49.5	53	0.12
ER⁺subgroup	46	61	0.002
Histological grade, number
1	3	35
2	8	22
3	7	18	0.055^a
Median tumor size, millimeters	15	15	0.95^b

Only cases from inclusion 1 are included. ^aFisher exact test. ^bWilcoxon rank sum test. ER = estrogen receptor; LR^-RT^-= no local recurrence, no radiotherapy given; LR^-RT⁺= no local recurrence after radiotherapy; LR⁺RT⁺= local recurrence developed after radiotherapy.
Niméus-Malmström et al. Breast Cancer Research 2008 10:R34 doi:10.1186/bcr1997