That news comes from two British studies that together looked at 2,400 patients with early breastcancercancer.
Both studies show better survival rates with epirubicin in addition to standard chemotherapy.
The results appear in The New England Journal of Medicine. Researchers include Christopher Poole, FRCP, of the Institute for Cancer Studies in Birmingham, England.
Chemo After Surgery
Most -- about 1,400 women -- were 50 or younger.
Half got epirubicin plus standard chemotherapy; the other half got standard chemotherapy without epirubicin.
In the epirubicin-plus-chemo group, 82% lived at least five years; 76% had no relapses during that time.
In the standard chemo group, a lower 75% lived at least five years; 69% had no relapses.
Epirubicin plus standard chemotherapy is "superior" to standard chemotherapy alone, the researchers conclude.
Though quality-of-life ratings during treatment were worse when epirubicin was added, journal editorialists called the side effects "tolerable."
The editorialists included Mark Levine, MD, of Canada's McMaster University and Juravinski Cancer Centre in Hamilton, Ontario.
Chemotherapy reduces the chance of breast cancer recurrence, but patients and their doctors need to weigh its risks and benefits, the editorialists note.
"Effective communication between the patient and the physician is essential, and the patient should be encouraged to participate in the decision-making process," they write.
The British studies were partly funded by Pharmacia (now Pfizer), which makes epirubicin. Poole and several colleagues report financial ties to drug companies, including Pfizer. Pfizer is a WebMD sponsor.
The editorialists note no financial disclosures.