Differences in Prognostic Factors and Failure Patterns Between Invasive @entity189 and XXXX With @entity513 of the Breast: Retrospective Multicenter Case-Control Study (KROG 13-06).

@entity1 @entity0 @entity5 @entity189 @entity513
PURPOSE: We designed the present study to investigate differences in prognostic factors and failure patterns between @entity1 with invasive @entity189 or @entity189 with micropapillary component (IMPC) and randomly matched @entity1 with @entity513 ( @entity513 ) of the breast at multiple institutions of the Korean Radiation Oncology Group (KROG). MATERIALS AND METHODS: This retrospective multicenter study was performed using subjects treated from January 1999 to November 2011. Female @entity1 who had undergone curative resection for @entity0 without neoadjuvant chemotherapy were considered for this study. Exact matches were made for age (    3  years), pathologic @entity5 and node stage, treatment method (surgery with or without radiotherapy), and period when surgery was performed (within 1 year) at the same institution. RESULTS: A total of 534 @entity1 were analyzed. The median follow-up period was 59 months in both groups. In the comparison of clinicopathologic characteristics, rates of lymphovascular invasion (LVI) and nuclear grade III were both significantly higher in IMPC than in @entity513 (P  < .001, P  =  .01, respectively). During the follow-up period, recurrences developed in 40 @entity1 with IMPC (15.0%) and 21 with @entity513 (7.9%). Locoregional recurrence (LRR) developed in 22 @entity1 with IMPC (8.2%) and 10 with @entity513 (3.7%). The rate of distant metastasis did not differ between the 2 groups (P  = .52). LRR-free survival (P  = .03) and recurrence-free survival (P  = .007) were significantly different between the 2 groups, but overall survival was not (P  = .67). CONCLUSION: IMPC is associated with a higher rate of LVI, high nuclear grade, and a propensity for LRR compared to @entity513 . Modification of the locoregional treatment modality might be needed in this pathologic subtype of @entity0 .
