In a nutshell
The present study compared the long-term efficacy and safety of different adjuvant chemotherapy regimens for breast cancer. Main results: chemotherapy clearly provides survival benefits; the higher the dosage, the higher the survival rates, despite more toxicity.
Some background
Many women with early stage breast cancer receive systemic (body-wide) anti-cancer treatment after surgery. Such treatment is called ‘adjuvant’ therapy, and may consist of chemotherapy. The goal of chemotherapy is to destroy remaining cancer cells and prevent relapse (recurrence of the cancer after a cancer-free period).
Standard adjuvant chemotherapy protocols for breast cancer are often based upon:
1. Drugs called Anthracyclines (Doxorubicin/Adriamycin; Epirubicin)
2. Taxane agents (Paclitaxel/Taxol; Docetaxel/Taxotere)
3. The triad of Cyclophosphamide (Cytoxan), Methotrexate, and Fluorouracil (Efudex) – CMF
Methods & findings
The authors analyzed cumulative data from 123 trials performed over 30 years including more than 100,000 women overall. These trials compared any of the following:
(1) Taxane-based versus non-taxane-based regimens
(2) Anthracycline-based regimens versus standard or modified CMF
(3) Higher versus lower Anthracyclines dosage
(4) Combination of chemotherapeutic drugs versus no adjuvant chemotherapy
This large analysis yielded the following findings:
A. Standard CMF and standard Anthracycline-based regimen (called ‘4AC’) were roughly equivalent; both reduced by one-third the 10-year rate of cancer recurrence, and by 20-25% the rate of death caused by cancer.
B. Regimens with lower dose in each cycle were less effective in reducing recurrence and mortality rates.
C. Regimens with substantially more chemotherapy (for example by adding cycles of Taxanes) and with more aggressive drugs lead to further reduction in mortality by 15-20% compared to standard protocols.
D. Taxane-plus-Anthracycline-based regimen seemed to be superior over Anthracyclines alone.
E. Most efficient regimens allow 36% reduction in 10-year breast cancer mortality comparing with no chemotherapy.
Importantly, the reductions in rates of recurrence and death did not depend on such factors as stage of disease, tumor size and aggressiveness, or age of the patient.
The bottom line
In general, the findings demonstrate that more chemotherapy means better survival benefits, despite more severe side effects.
Published By :
The Lancet
Date :
Feb 04, 2012
