Vinorelbine-based salvage therapy in HER2-positive metastatic breast cancer patients progressing during trastuzumab-containing regimens: a retrospective study

Filippo Montemurro¹ , Stefania Redana¹ , Franco Nolè² , Michela Donadio³ , Maria Elena Jacomuzzzi⁴ , Giorgio Valabrega¹ , Giuseppe Viale⁵ , Anna Sapino⁶ and Massimo Aglietta¹

¹Divisione di Oncologia Medica, AO Ordine Mauriziano/Istituto per la Ricerca e la Cura del Cancro, Candiolo, Torino, Italy

²Dipartimento di Oncologia Medica, Istituto Europeo di Oncologia (IEO), Milano, Italy

³Centro Oncologico Subalpino (COES), Torino, Italy

⁴Divisione di Ginecologia Oncologica, AO Ordine Mauriziano/Ospedale Mauriziano Umberto I, Torino, Italy

⁵Dipartimento di Patologia e Medicina di Laboratorio, Istituto Europeo di Oncologia (IEO), Milano, Italy

⁶Dipartimento di Scienze Biomediche e Oncologia Umana, Ospedale San Giovanni Battista- Molinette, Torino, Italy

author email corresponding author email

BMC Cancer 2008, 8:209doi:10.1186/1471-2407-8-209


Published:	24 July 2008

Abstract

Background

The vinka-alkaloyd vinorelbine is a potentially valuable treatment in patients with HER2-positive, trastuzumab-resistant advanced breast cancer. We sought to document the clinical activity of vinorelbine-based salvage treatments in this clinical setting.

Methods

We analyzed a cohort of 424 consecutive women receiving trastuzumab-based therapy for HER2-positive advanced breast cancer. Of these, 299 were identified as progressing during the initial trastuzumab-based treatment, and 77 received vinorelbine-based therapy as first salvage treatment. Central review of pathological specimens revealed that 70 patients had HER2-amplification detected by FISH. For these patients we determined overall response rate (ORR = complete-CR + partial-PR) and clinical benefit (CB = CR+PR+ Stable disease lasting at least 6 months), time to progression (TTP) and overall survival (OS) from the initiation of vinorelbine-based salvage therapy.

Results

In 60 patients who were evaluable for tumor response, ORR and CB rates were 28% (95% C.I. 18%-41%) and 50% (95% C.I. 38%-62%), respectively. Median follow-up from the initiation of salvage therapy was 15 months (range 1–63 months). Median TTP and OS were 7.1 months (95% C.I. 6.6–7.7 months) and 21 months (95% C.I. 14.3–27.7 months), respectively. No differences in clinical outcomes were observed according to whether vinorelbine was administered as a single agent or in combination with other cytostatics, or whether trastuzumab was stopped or continued beyond disease progression.

Conclusion

our findings suggests that vinorelbine-based combinations are active and should be further evaluated in studies conducted in trastuzumab-resistant patients, including those evaluating newer HER2-targeting agents.