In general , single-agent chemotherapy is not recommended for the adjuvant treatment of breast cancer in any patient population .
Anthracycline-taxane-based polychemotherapy regimens are , overall , considered superior to earlier-generation regimens and have the most significant impact on patient survival outcomes .
Regimens with varying anthracycline and taxane doses and schedules are options ; in general , paclitaxel given every 3 weeks is inferior .
Evidence does not support the use of bevacizumab in the adjuvant setting ; other systemic therapy agents such as metformin and vaccines remain investigatory .
BACKGROUND The Program in Evidence -Based Care ( pebc ) of Cancer Care Ontario recently created an evidence -based consensus guideline on the systemic treatment of early breast cancer .
The evidence for the guideline was compiled using a systematic review to answer the question " What is the optimal systemic therapy for patients with early-stage , operable breast cancer , when patient and disease factors are considered ? "
The question was addressed in three parts : cytotoxic chemotherapy , endocrine treatment , and human epidermal growth factor receptor 2 (her2)-directed therapy .
Intensified neoadjuvant chemotherapy in early-responding breast cancer: phase III randomized GeparTrio study.
BACKGROUND Patients with an early response to neoadjuvant chemotherapy  have chemosensitive tumors and a high probability for a pathological complete response at surgery . The relationship between extended chemotherapy and pathological complete response at surgery was investigated in a clinical trial . METHODS Untreated breast cancer patients received two 3-week cycles of docetaxel at 75 mg/m(2 ) , doxorubicin at 50 mg/m(2 ) , and cyclophosphamide at 500 mg/m(2 ) ( TAC ) . Those whose tumor size decreased by 50 % or more by sonographic measurement ( ie , reduction in the product of the two largest perpendicular diameters by at least 50 % ) were classified as responders and r and omly assigned to receive four or six more cycles of TAC , for a total of six or eight TAC cycles . The primary aim was to increase the rate of a pathological complete response ( defined as no invasive or in situ residual tumor masses in the breast and lymph nodes ) from 20 % to 26 % . Sonographic response rates and rates of breast-conserving surgery and adverse effects were also assessed . All statistical tests were two-sided . RESULTS Of the 2090 patients in the GeparTrio trial , 1390 ( 66.5 % ) were r and omly assigned as responders after two initial TAC cycles to receive an additional four ( n = 704 ) or six ( n = 686 ) TAC cycles . Rates of pathological complete response were not statistically significantly different between the arms ( 21.0 % with six TAC cycles and 23.5 % with eight TAC cycles ; difference = 2.5 % , 95 % confidence interval [ CI ] = -1.8 % to 6.8 % ; P = .27 ) . More clinical ( 48.2 % vs 52.9 % , difference = 4.7 % ; 95 % CI = -0.55 % to 9.95 % ; P = .08 ) and sonographic ( 22.6 % vs 27.6 % , difference = 5 % ; 95 % CI = 0.45 % to 9.55 % ; P = .033 ) complete responses at surgery were observed with eight TAC cycles than with six TAC cycles . The rate of breast-conserving surgery was similar in both arms ( 67.5 % vs 68.5 % , respectively , P = .68 ) . Grade 3 or 4 leukopenia and edema and various grade 1 or 2 adverse events were more frequent in patients receiving eight TAC cycles than in those receiving six cycles . CONCLUSION Patients receiving eight TAC cycles had statistically significantly higher sonographic response rates but not pathological complete response rates than those receiving six TAC cycles . However , they also had more toxic effects . So far , eight cycles of TAC can not be recommended for the whole group of patients responding to two initial cycles of TAC
In general , single-agent chemotherapy is not recommended for the adjuvant treatment of breast cancer in any patient population .
Anthracycline-taxane-based polychemotherapy regimens are , overall , considered superior to earlier-generation regimens and have the most significant impact on patient survival outcomes .
Regimens with varying anthracycline and taxane doses and schedules are options ; in general , paclitaxel given every 3 weeks is inferior .
Evidence does not support the use of bevacizumab in the adjuvant setting ; other systemic therapy agents such as metformin and vaccines remain investigatory .
BACKGROUND The Program in Evidence -Based Care ( pebc ) of Cancer Care Ontario recently created an evidence -based consensus guideline on the systemic treatment of early breast cancer .
The evidence for the guideline was compiled using a systematic review to answer the question " What is the optimal systemic therapy for patients with early-stage , operable breast cancer , when patient and disease factors are considered ? "
The question was addressed in three parts : cytotoxic chemotherapy , endocrine treatment , and human epidermal growth factor receptor 2 (her2)-directed therapy .