A novel way to predict whether women with ductal carcinoma in situ (DCIS) are at risk of developing more invasive tumours in later years has been discovered by scientists. DCIS is the most common form of non-invasive breast cancer.
According to the scientists, the discovery would give women with DCIS the opportunity to be more selective about their treatment.
"Women will have much more information, so they can better know their risk of developing invasive cancer. It will lead to a more personalized approach to treatment. As many as 44 percent of patients with DCIS may not require any further treatment, and can rely instead on surveillance," said lead author Karla Kerlikowske.
Researchers at the University of California, San Francisco and the San Francisco Veterans Affairs Medical Center followed the medical histories of 1,162 women aged 40 years and older who were diagnosed with DCIS and treated with lumpectomy.
They found that two factors were predictors of risk of developing invasive cancer within eight years after a diagnosis of DCIS: the method by which it was detected and expression of several biomarkers.
Findings showed that a breast lump that is diagnosed as DCIS was more predictive of a high risk of subsequent invasive cancer than DCIS diagnosis by mammography.
The study also found that different combinations of biomarkers measured on the initial DCIS tissue were associated with varying levels of risk of invasive cancer or DCIS.
These biomarkers include estrogen receptor, progesterone receptor, Ki67 antigen, p53, p16, epidermal growth factor receptor-2, and cyclooxygenase-2. Women who express high levels of p16, cyclooxygenase-2 and Ki67 were more likely to develop invasive cancer after their initial DCIS diagnosis.
According to Kerlikowske, because of the research, physicians will now be able to predict whether a DCIS patient treated by lumpectomy only will subsequently develop invasive cancer, DCIS, or be at very low risk of developing further tumours.
The study has been reported online by the Journal of the National Cancer Institute.