Local recurrence after ductal carcinoma in situ breast conserving treatment. Analysis of 195 cases.

PURPOSE: Ductal carcinoma in situ overall prognosis is excellent, but after breast conserving surgery, with or without radiotherapy, local recurrences can lead to locoregional or distant evolution and death. However, there are few data on optimal local recurrences treatment and long-term impact on survival. PATIENTS AND METHODS: This study included 195 women treated from 1985 to 1996 by conservative surgery (CS) or conservative surgery followed by radiotherapy (CS+RT), presenting local recurrences, with a 156-month median follow-up. RESULTS: Eighty-two out of 195 (42%) local recurrences were non-invasive (in situ) and 113 (58%) invasive. In situ local recurrence was discovered by mammography in 80.5% of the cases versus 47.5% for invasive local recurrence (P=0.0001). Salvage mastectomy was used in 53% of the cases after conservative surgery and 75% after conservative surgery followed by radiotherapy. The axillary nodal involvement rates were 11.8% and 25.8% among 17 and 62 patients with in situ and invasive local recurrences. Among 113 patients with invasive local recurrences and 82 with in situ local recurrences, 19 (16.8%) and three (3.6%) developed metastases, respectively. Among invasive local recurrences, comedocarcinoma subtype was highly predictive of subsequent metastases (32% versus 4.4%, P<0.0007). CONCLUSION: Invasive local recurrence after ductal carcinoma in situ treatment could be a dramatic event, fully changing long-term prognosis. Early mammographic local recurrence diagnosis (if possible still at non-invasive stage) seems essential to avoid or minimize metastatic risk. Mastectomy remains the safest option but, in some cases, a new conservative approach could be discussed.