Nineteen open label phase III RCTs (30,698 women) were included. Fourteen trials had a Jadad score of 3 and five trials had a score of 2.
A significant improvement in disease-free survival (HR 0.83, 95% CI 0.79 to 0.88; 19 RCTs, 8,426 events) and overall survival (0.83, 95% CI 0.77 to 0.90; 17 RCTs) was found with taxane-based adjuvant chemotherapy compared with taxane-free adjuvant chemotherapy. There was no evidence of significant statistical heterogeneity.
A significantly lower risk was also found in concurrent (five RCTs) and sequential regimens (14 RCTs) in the taxane-based treatment arm for disease-free survival. Other subgroup analyses according to menopausal status (six RCTs), oestrogen receptor status (11 RCTs), tumour sizes less than 2cm (four RCTs) and 2cm or more (five RCTs) and node status (node-negative patients, docetaxel-based treatment only) (four RCTs) also found a statistically significant benefit in favour of taxane-based adjuvant chemotherapy. The exceptions were for HER-2 status (positive and negative) and paclitaxel (every two weeks) where no significant between-group differences were found.
A significant increase in toxicity was associated with taxane-based adjuvant chemotherapy for neutropenia, febrile neutropenia, fatigue, diarrhoea, stomatitis and oedema; significant heterogeneity was found in these analyses.
There was no evidence of significant publication bias.