Abstract
The incidence of breast cancer in the Netherlands in women under 40 years has been more or less stable for the last 2 decades, while the mortality rate has decreased in the same period. Breast cancer in young women generally has a worse prognosis than in older women. Systemic therapy reduces the risk oflocoregional relapse after breast-conserving therapy from approximately 2% to less than 1% on an annual basis. Breast-conserving therapy therefore seems to be a safe option in young women who have consented beforehand to receive adjuvant systemic therapy. According to current treatment guidelines, adjuvant systemic therapy will be offered to approximately 80% of young breast cancer patients. The risk of premature postmenopausal symptoms, osteoporosis and unwanted infertility are, however, disadvantages of adjuvant chemotherapy and hormonal therapy. This specific treatment-related toxicity in young breast cancer patients requires support by experts with endowments for these specific issues.