Women under the age of forty with breast cancer who are given drugs in addition to lumpectomies or radiotherapy, known as adjuvant chemotherapy, may not be benefiting from these drugs. This is especially true if their tumors respond to changing levels of hormones such as estrogen, according to research published in the online journal, Breast Cancer Research.

"Developing breast cancer at a young age is very worrying in terms of survival," explained lead researcher Dr J van der Hage. "But some young women may be undergoing not only unpleasant but also unnecessary chemotherapy, which can be avoided."

Almost 10% of women diagnosed with breast cancer in Europe are under the age of forty. Two thirds of breast cancers, known as estrogen receptor positive (ER+), contain high levels of cells which contain estrogen receptors. These tumors tend to grow less aggressively than estrogen receptor negative (ER-) tumors. Young patients with breast cancer are currently advised to undergo courses of chemotherapy as well as removal of the tumor and/or entire breast. A research team of the European Organisation for Research and Treatment of Cancer (EORTC) selected patients from four EORTC-trials which were coordinated by Professor C.J.H. van de Velde from the Leiden University Medical Center, to study the effect of chemotherapy in young women. The research team found that ER+ patients, while they benefited from their chemotherapy treatment, did not survive at higher rates than ER- patients.

The difference in survival rates between the two treatment groups was just 5% (in favour of the ER- group), indicating that the chemotherapy gave no advantage. Of all the patients examined, including those who had only undergone primary treatment such as mastectomy, over 25% had died seven years after initial diagnosis.

"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," concluded Dr van der Hage.

Article: 'Efficacy of adjuvant chemotherapy according to hormone receptor status in young breast cancer patients', Jos A. van der Hage, Sven J.S.D. Mieog, Marc J. van de Vijver and Cornelis J.H. van de Velde, Breast Cancer Research