[1rarebird]

Ann Oncol. 2012 Feb 29. [Epub ahead of print]
Trastuzumab decreases the incidence of clinical relapses in patients with early breast cancer presenting chemotherapy-resistant CK19 mRNA-positive circulating tumor cells: results of a randomized phase II study.

Georgoulias V, Bozionelou V, Agelaki S, Perraki M, Apostolaki S, Kallergi G, Kalbakis K, Xyrafas A, Mavroudis D.
Source

Department of Medical Oncology, University Hospital of Heraklion, Heraklion.

Abstract

BACKGROUND:

Since the detection of circulating tumor cells (CTCs), which express that human epidermal growth factor receptor 2 (HER2) is an adverse prognostic factor in early breast cancer patients, we investigated the effect of trastuzumab on patients' clinical outcome.
PATIENTS AND METHODS:

Seventy-five women with HER2-negative breast cancer and detectable CK19 messenger RNA (mRNA)-positive CTCs before and after adjuvant chemotherapy were randomized to receive either trastuzumab (n = 36) or observation (n = 39). CK19 mRNA-positive CTCs were detected by RT-PCR and double-stained CK-positive/HER2-positive cells by immunofluorescence. The primary end point was the 3-year disease-free survival rate.
RESULTS:

Fifty-one (89%) of the 57 analyzed patients had HER2-expressing CTCs. After trastuzumab administration, 27 of 36 (75%) women became CK19 mRNA negative compared with 7 of 39 (17.9%) in the observation arm (P = 0.001). After a median follow-up time of 67.2 months, 4 (11%) and 15 (38%) relapses were observed in the trastuzumab and observation arm, respectively (P = 0.008); subgroup analysis indicated that this effect was mainly confined to women with more than three involved axillary lymph nodes (P = 0.004). The median DFS was also significantly higher for the trastuzumab-treated patients (P = 0.008).
CONCLUSION:

Administration of trastuzumab can eliminate chemotherapy-resistant CK19 mRNA-positive CTCs, reduce the risk of disease recurrence and prolong the DFS.