Low dose gemcitabine plus cisplatin in a weekly-based regimen as salvage therapy for relapsed breast cancer after taxane-anthracycline-containing regimens.

PURPOSE: Cisplatin-gemcitabine is a synergistic chemotherapy (CT) combination highly proven in a broad spectrum of epithelial neoplasms and shows a non-cross-resistance profile with the most active drugs in metastatic breast cancer (MBC). We have conducted an exploratory study to determine if treatment with low doses of a combination of fixed-rate gemcitabine infusion and cisplatin was clinically meaningful in women relapsing after a minimum of 2 prior lines of CT for advanced disease (range 2-6), which had to have necessarily included both anthracyclines and taxanes. Another goal was to find the optimal individual schedule by adjusting frequency and dosage according to patient tolerability. PATIENTS AND METHODS: From May 2002 to November 2003, 22 patients with relapsed advanced BC and a minimum of two prior CT lines were offered treatment with gemcitabine (G) (initial dose 750 mg/m(2), or 600 mg/m(2) if the patient had received more than two previous CT lines) plus cisplatin (P) (initial dose 30 mg/m(2), or 20 mg/m(2) in case of > or =3 prior CT lines) on days 1 and 8 of a 21-day cycle. Treatment was postponed to day 15 if it could not be given on day 8, without dose reduction. If treatment could not be given on day 15, a 20% dose reduction was allowed and treatment given the next week. Further dose reductions were allowed as needed up to a maximum of three. Treatment continued until disease progression or intolerable toxicity. Median age was 54.5 years (35-75). Median Karnofsky was 90 (range 80-90). Median number of prior CT lines was 3 (2-6). 90.9% of patients had received adjuvant CT. All had prior anthracyclines and taxanes. Other agents used included 5-FU/eniluracil, MTA, RPR 109881A, trastuzumab, cisplatin, VP16, vinorelbine, capecitabine and irinotecan. 72.7% had received radiotherapy and 68.1% hormonal therapy (median 2 lines, range 1-4).
RESULTS: Partial responses (PR) were seen in 9.1% of patients and stable disease (SD) in 36.4%. Clinical Benefit Rate (PR+SD) was derived in 45.5% of patients. Median time to progression was 4 months (95% CI, 3-5) in general and 6 months (95% CI, 4-8) in patients with clinical benefit. Median survival for the entire group was 8 months (95% CI, 5-11) and 19 months when clinical benefit was obtained (95% CI, 11-25). Patients received a median of 8.5 CT administrations (range, 2-45). Forty-three percent of doses were delayed. Sixteen out of 22 patients needed a delay and/or reduction of initial dose. Cisplatin and gemcitabine doses were reduced in 75% and 62% of all cycles, respectively. Sixteen out of 22 patients needed a delay and/or reduction of initial dose. Toxicities grade >3 were neutropenia 35% and thrombocytopenia 15%. All other toxicities were grade 2 or less, including sensorial neuropathy (30%), asthenia (34%), nausea/vomiting (20%) and oral mucositis (15%). There were no treatment-related deaths. Reasons for discontinuation were progression (18 patients), death (3 patients) and patient decision (1 patient).
CONCLUSION: Weekly cisplatin-gemcitabine with flexible downwards individual tailoring is a safe and effective salvage treatment in heavily pretreated MBC patients with good PS.