Treatment of ductal carcinoma in situ after excision: would a prophylactic paradigm be more appropriate?

Corresponding to the increased use of mammography, the incidence of ductal carcinoma in situ (DCIS) has risen dramatically in the past 30 years. Despite its growing incidence, the treatment of DCIS remains highly variable and controversial. Although DCIS itself does not metastasize and is never lethal, it may be a precursor of invasive breast cancer and is a marker of increased breast cancer risk. Confusing a precursor lesion with cancer, many clinicians apply an invasive breast cancer treatment paradigm to DCIS patients, offering adjuvant radiation therapy and tamoxifen after diagnosis. In this commentary, we outline the issues associated with DCIS management--is DCIS a cancer, a precursor of cancer, or a marker of invasive carcinoma risk? Specifically, we argue that consideration be given to removing the term "carcinoma" from DCIS, using cancer "occurrence" to mean the diagnosis of invasive cancer after DCIS instead of "recurrence," and make the argument that a prophylactic paradigm of treatment after excision may be more appropriate.