Search

Background: Various patient, treatment, and pathologic factors have been associated with an increased risk of local recurrence (LR) following breast-conserving therapy (BCT) for ductal carcinoma in situ (DCIS). However, the strength and importance of individual factors has varied; whether combining factors improves prediction, particularly in community practice, is uncertain. In a large, population-based cohort of women with DCIS treated with BCT in three community-based practices, we assessed the validity of the Memorial Sloan-Kettering Cancer Center (MSKCC) DCIS nomogram, which combines clinical, pathologic, and treatment features to predict LR., Methods: We reviewed slides of patients with unilateral DCIS treated with BCT. Regression methods were used to estimate risks of LR. The MSKCC DCIS nomogram was applied to the study population to compare the nomogram-predicted and observed LR at 5 and 10 years., Results: The 495 patients in our study were grouped into quartiles and octiles to compare observed and nomogram-predicted LR. The 5-year absolute risk of recurrence for lowest and highest quartiles was 4.8 and 33.1 % (95 % CI 3.1-6.4 and 24.2-40.9, respectively; p < 0.0001). The overall correlation between 10-year nomogram-predicted recurrences and observed recurrences was 0.95. Compared with observed 10-year LR rates, the risk estimates provided by the nomogram showed good correlation, and reasonable discrimination with a c-statistic of 0.68., Conclusions: The MSKCC DCIS nomogram provided good prediction of the 5- and 10-year LR when applied to a population of patients with DCIS treated with BCT in a community-based practice. This nomogram, therefore, is a useful treatment decision aid for patients with DCIS.

Purpose: The optimal treatment strategy for ductal carcinoma in situ (DCIS) continues to evolve and should consider the consequences of initial treatment on the likelihood, type, and treatment of recurrences., Methods: We conducted a retrospective cohort study using two data sources of patients who experienced a recurrence (DCIS or invasive cancer) following breast-conserving surgery (BCS) for index DCIS: patients with an index DCIS diagnosed from 1997 to 2008 at the academic institutions of the National Comprehensive Cancer Network (NCCN; N = 88) and patients with an index DCIS diagnosed from 1990 to 2001 at community-based integrated healthcare delivery sites of the Health Maintenance Organization Cancer Research Network (CRN) (N = 182)., Results: Just under half of local recurrences in both cohorts were invasive cancer. While 40 % of patients in both cohorts underwent mastectomy alone at recurrence, treatment of the remaining patients varied. In the earlier CRN cohort, most other patients underwent repeat BCS (39 %) with only 18 % receiving mastectomy with reconstruction, whereas only 16 % had repeat BCS and 44 % had mastectomy with reconstruction in the NCCN cohort. Compared with patients not treated with radiation, those who received radiation for index DCIS were less likely to undergo repeat BCS (NCCN: 6.6 vs. 37 %, p = 0.001; CRN: 20 vs. 48 %, p = 0.0004) and more likely to experience surgical complications after treatment of recurrence (NCCN: 15 vs. 4 %, p = 0.17; CRN: 40 vs. 25 %, p = 0.09)., Conclusion: We found that treatment of recurrences after BCS and subsequent complications may be affected by the use of radiotherapy for the index DCIS. Initial treatment of DCIS may have long-term implications that should be considered.