Ductal carcinoma in situ: trends in geographic, temporal, and demographic patterns of care and survival.

While long-term prognosis is excellent, treatment of ductal carcinoma in situ (DCIS) remains controversial and inconsistent. The purpose of this study was to track geographic and temporal patterns of care for women diagnosed with DCIS, and analyze subsequent cancer-specific risk of mortality. Subjects for this study were 41,245 women diagnosed with primary DCIS in the National Surveillance, Epidemiology, and End Results (SEER) program from 1973 through 2000. Variables analyzed included patient age, year of diagnosis, SEER site of residence at the time of diagnosis, treatment (surgery, radiation), race, age, and hormone (estrogen and progesterone) receptor status. The percentage of women diagnosed with DCIS out of the total number of women diagnosed with breast cancer increased steadily between 1973 and 2000, with the largest increase occurring around 1985. Breast conserving surgery (BCS) utilization increased over time for each SEER site to the current proportions, ranging from 49.5% in Utah to 76.9% in Connecticut. Younger women were significantly more likely to receive mastectomy and had significantly lower risk of death. Women receiving BCS who also had radiation therapy (RT) had a significantly lower risk of death, although those receiving mastectomy had the lowest risk of death. Black women and Asian/Pacific island women were significantly more likely to receive BCS, although black women were less likely to receive follow-up RT and had a significantly increased risk of death. Racial and age differences in the treatment of DCIS resulted in significantly disparate rates of survival, which should be considered in public health programming. Mastectomy utilization resulted in improved survival, although additional studies may elucidate the interaction of treatment with patient age.