Meta-analysis of trials comparing anastrozole and tamoxifen for adjuvant treatment of postmenopausal women with early breast cancer

Table 1 Summary of trials included in meta-analysis

Trial	ATAC[4–6]	ITA[7, 8]	ABCSG trial 8[9, 12]	ARNO 95 trial[9, 13]
Study design	Multicenter, randomized	Multicenter, randomized	Multicenter, randomized	Multicenter, randomized
Patients	Postmenopausal, receptor status +/unknown	Postmenopausal, estrogen receptor (+), received 2–3 years of tamoxifen
Sample size	9366	448	2529	979
Median follow-up (months)	68	64	31	30
Treatment regimen	Upfront^a	Switching^b	Sequencing^c	Switching^b
Estrogen receptor status ^d
Positive	83.7%	91.0%	99.0%	97.1%
Negative	8.3%	1.0%	1.0%	-
Unknown	8.0%	8.0%	-	2.9%
Hazard ratios for event free survival (95% CI)	All patients: 0.81 (0.73–0.91) ER positive patients: 0.76 (0.67–0.87)	0.57 (0.38–0.85)	0.68 (0.49–0.91)	0.66 (0.44–1.00)

^aInitial treatment with anastrozole or tamoxifen alone or in combination up to 5 years
^bSwitching to anastrozole after 2–3 tamoxifen vs. continued tamoxifen for 5 years
^cSequencing prospectively to anastrozole vs. tamoxifen after 2 years of tamoxifen treatment
^dFor patients in anastrozole arm

ISSN: 1745-6215