[The treatment of ductal carcinoma in situ (DCIS) of the breast].

Ductal carcinoma in situ (DCIS) of the breast is diagnosed more and more often in the Netherlands as a result of mammographic population screening and improved mammography techniques. Mastectomy and local excision, with or without radiotherapy, are used for the treatment of DCIS, but breast-conserving therapy seems a logical option in view of the favourable prognosis. Radiotherapy following total excision of DCIS reduces the local recurrence rate by half. Incomplete excision of DCIS is associated with a higher rate of local recurrence, which is invasive in about 50% of the cases and can therefore affect the prognosis adversely. There are conflicting opinions in the literature as to which patients with DCIS can be treated with breast-conserving therapy and whether local excision should be followed by radiotherapy, as is the case for breast-conserving treatment of invasive mammary carcinoma. The diagnosis and treatment of DCIS are therefore complex and require a multidisciplinary approach. Patients may be selected for breast-conserving therapy on the basis of diagnostic characteristics and risk factors.