Adjuvant chemotherapy does not seem to improve long-term survival among women less than forty years of age with breast cancer, especially if their tumours respond to oestrogen, according to Breast Cancer Research.

Researchers from the European Organisation for Research and Treatment of Cancer (EORTC) reviewed four trials that enrolled 9,938 breast cancer patients. At the time of diagnosis, 934 patients were 40 years old or younger. The researchers determined whether tumour samples collected from 480 patients aged 40 years old or younger were oestrogen receptor positive (ER+) or negative (ER-).

Over the median follow-up of 7.3 years, 22% of the patients died. Overall, ER+ women showed a better prognosis than those negative for oestrogen receptors. Survival rates at 7 years were 82% and 77% in the ER+ and ER- groups respectively. Ninety per cent and 77% of ER+ and ER- patients respectively who did not receive adjuvant systemic chemotherapy survived 7 years. However, in the 200 patients who received adjuvant systemic chemotherapy, survival rates at 7 years were 70% and 75% for the ER+ and ER- groups respectively.

“Young patients with hormone receptor-positive tumours benefit less from adjuvant systemic chemotherapy than patients with hormone receptor-negative tumors,” the authors concluded. “These results confirm that chemotherapy alone cannot be considered optimal adjuvant systemic treatment in breast cancer patients 40 years old or younger with hormone receptor-positive tumours.”

Undergoing unnecessary chemo?

"Adjuvant chemotherapy is a well established, but ineffective treatment in ER+ breast cancer patients aged 40 years or less. Hormone responsiveness is the key to tailoring therapy in the future fight against this disease for young women," adds lead researcher Professor Cornelis van de Velde from the Leiden University Medical Center. "Developing breast cancer at a young age is very worrying in terms of survival. But some young women may be undergoing not only unpleasant but also unnecessary chemotherapy, which can be avoided."

During 2004, doctors diagnosed approximately 36,900 new breast cancers in England, accounting for 32% of all cancers in women. Around 10,300 women died from breast cancer in England in 2004. The incidence peaks between 55 and 64 years of age. However, almost one-in-ten of European women diagnosed with breast cancer are under forty years. Two-thirds of breast cancers are ER+ and tend to grow less aggressively than ER- tumours.