Preliminary results of a randomized phase II study of paclitaxel and bevacizumab ± gemcitabine as first-line treatment for metastatic breast cancer

1089

Background: The addition of bevacizumab (B) to paclitaxel (P) results in a significant improvement in PFS in pts with metastatic breast cancer (MBC) (Miller K, et al. New Engl J Med 2007). A randomized Phase II trial examining the efficacy and safety of adding gemcitabine (G) to the PB doublet has completed enrollment. Reported here are preliminary efficacy and safety results. Methods: This is a US, multicenter, randomized, superiority trial. Eligible pts have locally advanced or metastatic breast cancer, ECOG PS 0 or 1, and no prior cytotoxic therapy for metastatic disease. Prior adjuvant or neoadjuvant treatment with a taxane or endocrine therapy is allowed. Pts are randomized to receive P 90 mg/m2 on Days 1, 8, and 15, followed by B 10 mg/kg on Days 1 and 15 of a 28-day cycle, or the same regimen plus G 1,500 mg/m2 on Days 1 and 15. Primary endpoint is response rate according to RECIST criteria. Results: Between May 2006 and February 2008, 189 women were randomized to treatment. The table below summarizes currently available results. Grades 1–2 alopecia occurred in 28% of pts in the PB arm and in 38% of pts in the PB+G arm. One pt (2%) in the PB arm experienced a Grade 3 nosebleed. Grades 3 and 4 thrombotic events occurred respectively in 0% and 2% of pts in the PB arm, and in 3% and 2% of pts in the PB+G arm. Four pts (7%) in the PB arm and 3 pts (5%) in the PB+G arm discontinued due to treatment-related AEs. Three on-study deaths have occurred, none deemed related to study treatment. Conclusions: Study follow-up is ongoing. Full results will be available at the time of the meeting. Therapy with PB ± G is feasible and does not appear to be associated with significant bleeding or thrombotic events. As expected, the addition of G to the PB doublet appears to increase the incidence of neutropenia in pts with MBC.

[Table: see text]

[Table: see text]

Detecting circulating tumor cells in metastatic breast cancer patients using fiber-optic array scanning technology

1022

Background: Circulating tumor cell (CTC) detection and enumeration has been shown to be a valuable tool for determining prognosis in metastatic breast cancer patients. CTCs are rare, existing in the circulation at estimated concentrations of 1 in 1 - 10 million normal blood cells. To date, the most widely used technique to detect CTCs has used immunomagnetic enrichment based protocols. In this validation study, we sought to determine if an enrichment free approach using an immunofluorescent cell attachment protocol along with fiber-optic array scanning technology (FAST) could achieve similar results. Methods: We have developed and validated a scanning instrument using FAST that can be used in conjunction with an immunofluorescence staining protocol to efficiently detect CTCs. The protocol uses a pan anti-cytokeratin antibody cocktail directed against 9 cytokeratins along with a DAPI nuclear counterstain. FAST defines cell positions, so relocation and retrospective analysis of CTCs is possible. Using this system, we assayed 50 blood specimens obtained from metastatic breast cancer patients. Pathologic review of CTCs was performed identifying CTCs as cytokeratin positive and DAPI positive. Survival analyses were determined using Kaplan-Meier analyses. Results: 31 women with metastatic breast cancer were enrolled in the study and provided 50 peripheral blood specimens. The median CTC count for patients with progressive disease was 8.5, while the median CTC count for patients with stable or responding disease was 1. At a median follow-up of 1 year, 11 patients had died. Patients with =5 CTCs had a median survival of 212 days, while the median survival for patients with 0–4 CTCs had not been reached after 1 year (p=0.0012). Patients with progressive disease had significantly higher CTC counts (p<0.0001) than those who were stable or responding to therapy. Conclusions: This study confirms the previously reported efficacy of CTC enumeration in determining the prognosis of metastatic breast cancer patients and establishes the potential utility of the FAST cytometer as a method for CTC enumeration.

No significant financial relationships to disclose.

Outpatient high-dose chemotherapy with autologous stem-cell rescue for hematologic and nonhematologic malignancies

PURPOSE

A prospective study to determine the feasibility of high-dose chemotherapy (HDC) and autologous stem-cell rescue (ASCR) in the outpatient setting.

METHODS

One hundred thirteen consecutive patients underwent 165 cycles of HDC/ASCR for a variety of malignancies. HDC regimens were disease-specific. Initially, patients were hospitalized for HDC, discharged on completion, and maintained as outpatients unless toxicities required rehospitalization (subtotal outpatient transplantation [STOT]). Once this was established as safe, a total outpatient transplant (TOT) program was developed in which patients received all of the HDC, as well as supportive care, as outpatients. Patients who declined the outpatient programs received the same HDC and supportive care as inpatients.

RESULTS

In 140 of 165 (85%) HDC cycles, patients agreed to participate in one of the outpatient transplant programs. Five patients in the STOT program could not be discharged from the hospital because of toxicities that developed during HDC; thus, 135 patients were monitored the outpatient setting, 95 (70%) of whom were never readmitted. The mean +/- SEM total hospital length of stay (LOS), including all readmissions and excess days after chemotherapy, was 18.33 +/- 5.06 days for patients who refused the outpatient program, 8.22 +/- 5.76 days for patients in the STOT program, and 2.81 +/- 7.66 days for those in the TOT program (P < .001). One treatment-related death occurred in each treatment setting: day 120 inpatient, day 17 STOT, and day 110 TOT.

CONCLUSION

Outpatient management of HDC/ASCR is safe and acceptable for the vast majority of patients. The STOT program resulted in significant reduction in hospital LOS, while the TOT program appears equally safe and further reduces LOS. Hospitalization for HDC/ASCR is unnecessary in most patients.

Alternating combination chemotherapy for stages III and IV ovarian carcinoma

Thirty-nine previously untreated patients with stages III and IV ovarian carcinoma were treated with debulking surgery, followed by alternating combination chemotherapy with cisplatin, Adriamycin (Adria Laboratories, Columbus, Ohio), and cyclophosphamide (PAC); and hexamethylmelamine, cyclophosphamide, methotrexate, and 5-fluorouracil (HexaCAF). Of 19 patients with measureable disease at the onset of therapy, ten (53%) had at least a partial response to chemotherapy. Seven (18% of total) patients were found to be pathologically free of disease at secondlook surgery, but four patients relapsed 19 to 31 months after initiating therapy. The median progression-free survival period of all 39 patients entered into the study is 12 months, and the median crude survival is 21 months. The PAC/HexaCAF alternating combination chemotherapy regimen may be administered with moderate toxicity, but the treatment results are not superior to those reported for PAC or HexaCAF alone in advanced ovarian carcinoma.