Bone marrow disseminated tumor cells, loco-regional and adjuvant treatment are prognostic factors for loco-regional relapses in early breast cancers.

Abstract

Abstract Abstract #307 Purpose: To study in early breast cancer (BC) patients (pts) if bone marrow (BM) disseminated tumor cells (DTC) are associated with a specific loco-regional dissemination of cancer cells, according to the radiotherapy fields and to the pattern of loco-regional relapses.
 Patient and methods: BM aspirates were prospectively screened for cytokeratin positive (CK+) cells at primary treatment in stage I-III BC pts. Local recurrence (LR) was defined as recurrence of the breast or chest wall; Regional recurrence (RR) was defined as lymph node recurrence after loco-regional treatment. Irradiation fields, BM DTC status, clinical and pathological variables of the pts were correlated with loco-regional relapse-free survival (LRRFS).
 Results: BM DTC were detected in 94 out of 621 pts (15%) and were not associated with the axillary lymph node status and other prognostic factors. After a median follow-up of 56 months, 18 pts (2,9%) experienced loco-regional relapses: 15 LR occurred in the RT fields whereas 2 LR and 1 RR were out. 8 of the 18 relapsing pts (44%) were DTC positive (8 LR in the RT fields). BM DTC detection was the only prognostic factor for LRRFS (p=0.0005, OR=5.2 [2.0-13.1]) in multivariate analysis. In BM DTC positive patients, longer LRRFS were observed in those who were given adjuvant hormonal therapy (p=0.03) and RT on supra-clavicular (SCN) and internal mammary (IMN) nodes (p=0.055) (multivariate analysis).
 Conclusions: BM DTC strongly influence loco-regional relapse in early BC patients. Our data support the hypothesis of a different lymphatic spread of BM DTC positive BC and of a possible re-seeding of BM DTC to the breast. Survival analyses suggest that BM DTC positive patients take advantage of adjuvant hormone therapy but also of adjuvant SCN and IMN irradiation. This observation could be one explanation of the influence of systemic treatment on locoregional relapse and of radiotherapy on distant metastatic dissemination. Citation Information: Cancer Res 2009;69(2 Suppl):Abstract nr 307.