Table 1. Description of the study sample.

Continuous variables	mean±s.d.
Age (years)	64.4±6.5
ER expression (Allred score)	6.61±1.20
PgR expression (Allred score)	4.91±1.81
Ki-67 (%)	31.0±13.8
Categorical and ordinal variables	N (%)
Histological type
Invasive ductal carcinoma	18 (78.3)
Infiltrative lobular carcinoma	5 (21.7)
Grade
1	2 (8.7)
2	10 (43.5)
3	11 (47.8)
Adjuvant radiotherapy
Yes	22 (95.6)
No	1 (4.4)
Adjuvant chemotherapy
Anthracyclin based	5 (21.7)
Taxane based	3 (13.0)
Anthracyclin plus taxane based	13 (56.5)
Unknown	1 (4.4)
No	1 (4.4)
Type of AI administered
Non-steroidal (letrozole or anastrozole)	19 (82.6)
Steroidal (exemestane)	4 (17.4)
Co-administration of goserelin
Yes	17 (73.9)
No	6 (26.1)
Line of treatment
First	14 (60.9)
Second	9 (39.1)
Best response
PD	4 (17.4)
SD	13 (56.5)
PgR	6 (26.1)

Abbreviations: AI=aromatase inhibitor; ER=oestrogen receptor; PD=progressive disease; PgR=progesterone receptor; SD=stable disease.