Risk Factors that Contribute to the Progression of DCIS to Invasive Breast Cancer
Several risk factors have been identified by researchers that can contribute to the progression of ductal carcinoma in situ (DCIS) to invasive breast cancer. These factors include increased exposure to estrogen, the use of hormone replacement therapy, as well as the age at which a woman experiences her first period, first live birth, and onset of menopause. Additionally, individuals with first-degree relatives who have been diagnosed with breast cancer also have a higher risk of progression.
Diagnosis
In the diagnosis of ductal carcinoma in situ (DCIS), approximately 90 percent of cases are identified through regular mammogram screenings. Suspicion of DCIS arises when small calcifications in branching patterns are observed. To confirm the presence of DCIS and determine if the cancer is non-invasive or invasive, a diagnostic mammogram and a core needle biopsy are performed. It is possible for individuals with DCIS to also have invasive breast cancer. Even if a needle biopsy indicates DCIS, there is a 10 to 20 percent chance that the cancer is invasive, although this is usually not confirmed until after surgery. Invasive characteristics are more likely in cases of large or fast-growing DCIS lesions.