Rates of high-grade DCIS increase with age

Mammography screening detects more cases of high-grade ductal carcinoma in situ (DCIS) as women age, according to a new study published online in Radiology.

DCIS is a common finding on mammography, and all grades of DCIS can develop into invasive cancer if left untreated -- with high-grade DCIS developing faster and more aggressively. Yet some clinicians believe DCIS is overtreated because some types may never progress to become clinically symptomatic.

A team led by Dr. Stefanie Weigel of University Hospital Muenster in Germany sought to investigate the incidence and grade of DCIS as women age. The study included 733,905 women between the ages of 50 and 69 who were taking part in a screening program for the first time. The researchers divided the women into five-year age groups and then calculated the rates of high-grade, intermediate-grade, and low-grade DCIS (Radiology, October 27, 2015).

Of the total cohort, 989 women, or 1.4%, had DCIS. Of these, 419 had high-grade DCIS, 388 were intermediate-grade, and 182 were low-grade. But the rate of intermediate- and high-grade DCIS showed a statistically significant increase with age, with a rate peak in the oldest age group of 65 to 69 years.

The findings suggest that more research is needed on the effectiveness of standard DCIS treatment in women older than 60, according to Weigel.

"Adequate therapy of nonsymptomatic high-grade DCIS detected at screening needs further evaluation, as there is the chance to prevent aggressive invasive breast cancer, which could be life-threatening even in older age groups," Weigel said in a statement released by RSNA. "In terms of overdiagnosis and overtreatment, there is need for more detailed prognostic characterization of DCIS lesions and weighting them in the context of age."