Paclitaxel as second and subsequent therapy for metastatic breast cancer: activity independent of prior anthracycline response

Personalized medicine in breast cancer: pharmacogenomics approaches

Abstract: Breast cancer is the fifth cause of cancer death among women worldwide and represents a global health concern due to the lack of effective therapeutic regimens that could be applied to all disease groups. Nowadays, strategies based on pharmacogenomics constitute novel approaches that minimize toxicity while maximizing drug efficacy; this being of high importance in the oncology setting. Besides, genetic profiling of malignant tumors can lead to the development of targeted therapies to be included in effective drug regimens. Advances in molecular diagnostics have revealed that breast cancer is a multifaceted disease, characterized by inter-tumoral and intra-tumoral heterogeneity and, unlike the past, molecular classifications based on the expression of individual biomarkers have led to devising novel therapeutic strategies that improve patient survival. In this review, we report and discuss the molecular classification of breast cancer subtypes, the heterogeneity resource, and the advantages and disadvantages of current drug regimens with consideration of pharmacogenomics in response and resistance to treatment.

Paclitaxel Administered Weekly in Patients with Docetaxel-Resistant Metastatic Breast Cancer: A Single-Center Study

Aims and background

We evaluated retrospectively the efficacy and toxicity of paclitaxel in patients with docetaxel-resistant metastatic breast cancer.

Study design

Paclitaxel (80 mg/m2) was administered weekly to 44 patients who had previously received chemotherapy regimens for metastatic breast cancer. All patients had progressive disease in spite of having received docetaxel therapy.

Results

Treatment was repeated until there was evidence of disease progression. Objective responses were obtained in 14 of 44 assessable patients (31.8%; 95% confidence interval, 17.5–46.1). Fourteen patients had partial responses; none responded completely. Seven of 14 responders had primary resistance to docetaxel therapy. The median duration of response was 6.1 months (range, 2.1–12.7). The median time to progression was 5.0 months. Clinically severe adverse events (grade 3 or 4) included neutropenia (27.2%), leukopenia (25.0%), neuropathy-sensory (13.6%), febrile neutropenia (6.8%), anemia (2.2%), constipation (2.2%), and edema (2.2%). Treatment was generally well tolerated and could be continued on an out-patient basis.

Conclusions

Weekly paclitaxel is effective in patients with docetaxel-resistant metastatic breast cancer. This observation suggests partial cross-resistance between paclitaxel and docetaxel. There was no evidence for additive cumulative toxic effects of the two taxanes.

Long-Term, weekly One-Hour Infusion of Paclitaxel in Patients with Metastatic Breast Cancer: A Phase II Monoinstitutional Study

Aims and background

A dose-dense therapy with weekly paclitaxel given as a 1-hr infusion yielded a 53% overall response rate in breast cancer patients resistant to anthracyclines, with a remarkable lack of neutropenia (Seidman, 1998). We performed a monoinstitutional phase II trial in order to confirm these interesting results.

Patients and methods

Eligibility criteria included advanced breast cancer and no taxane pretreatment. Paclitaxel was administered weekly at the dose of 90 mg/m2 (60 mg/m2 in patients at high risk of toxicity) by 1-hr iv infusion. Fifty-eight patients entered the trial. Median age was 54 years (range, 38-72). Performance status was good (median 1; range, 0-2). Fifty-two patients were pretreated with anthracyclines.

Results

A total of 1,004 weekly paclitaxel infusions were administered (median, 19 per patient; range, 4-43). The median delivered dose intensity was 67.4 mg/m2/week (range, 43-86). Twenty-eight of the 58 assessable patients obtained an objective response (48%), 15 had stable disease (26%) and 15 progressed (26%). The overall response rate was 48% (95% confidence interval, 35-61%) with 5 complete responses (8%). In anthracycline-pretreated patients, 23/52 (44%) responses were observed. Median duration of response was 5 months (range, 3-27). Toxicity was acceptable apart from a case of pulmonary embolism in a 70-year-old patient, 1 case of congestive heart failure in an anthracycline-pretreated patient aged 64, and 9 cases of G3 neutropenia. Peripheral neuropathy was observed in 38 patients (64%), usually of a mild grade; alopecia in 45 patients (78%) and onychopathy in 16 (28%), usually of a mild grade apart from 2 cases requiring treatment interruption. Tachycardia and atrial fibrillation occurred in a 55-year-old woman.

Conclusions

Our data seem to confirm the activity and safety of this approach even in a heavily pretreated population of patients. Its combination with other active drugs needs to be further investigated in clinical trials.

Paclitaxel and Doxorubicin Combination in the First-line Treatment of Metastatic Breast Cancer

Anthracyclines and taxanes are currently the most effective drugs in the treatment of metastatic breast carcinoma. The aim of this study was to determine the efficacy and toxicity of paclitaxel and doxorubicin combination in the first-line treatment of metastatic breast cancer. Forty-five women with metastatic breast cancer were recruited in the study. Median age was 49 years (range, 33-70). Treatment protocol: doxorubicin (50 mg/m2/day, 30-min infusion) followed by paclitaxel (200 mg/m2/day, 3-hr infusion) every 3 weeks. Response rates included complete response in 13 (28.9%) patients and partial response in 19 (42.2%) patients, with an overall response rate of 71%. Five (11%) patients had stable disease and 8 (18%) patients had progressive disease. At a median follow-up of 19.7 months, median time to progression for all patients was 19.9 months (95% confidence interval, 12.8 to 27 months). Median overall survival time was 28.4 months. Grade 3-4 nausea/vomiting and hematological toxicities were observed in 12 (26%) and 6 (13.3%) patients, respectively. Cardiac toxicity was observed in 2 (4.4%) patients. In this trial, paclitaxel and doxorubicin combination was demonstrated to be a favorable and active regimen in the first-line treatment of metastatic breast cancer.

Paclitaxel Activity in Anthracycline Refractory Breast Cancer Patients

Aims and background

We investigated the efficacy and tolerability of two doses of paclitaxel, 175 mg/m2 and 135 mg/m2, over a 3-hr infusion, without prophylactic G-CSF, in heavily pretreated patients with anthracycline-resistant breast cancer. Although paclitaxel may share with anthracyclines a common mechanism of drug resistance, there is evidence that the two drugs are not completely cross resistant.

Methods

From July 1994 to January 1996, 42 patients were treated every 3 weeks, for a maximum of 6 cycles; paclitaxel dose was established according to pretreatment extension.

Results

In 41 assessable patients we observed 9 partial responses, for an overall response rate of 22% (95% CI, 10–34%). There was no difference in response rate between the two dose levels. Median duration of response was 9 months, median time to progression 5 months, and median survival 9 months. The dose-limiting toxicity was neutropenia, which was grade 3–4 in 40% (135 mg/m2) and 62% (175 mg/m2) of the patients (P = 0.28); neutropenic fever occurred in 24% of the patients, without significant differences between the two dose levels. Other toxicity was mild to moderate.

Conclusions

Paclitaxel at doses of 175 mg/m2 or 135 mg/m2 is active and well tolerated in advanced breast cancer patients resistant to anthracyclines. The prophylactic use of colony-stimulating factors seems appropriate in heavily pretreated patients given the higher dose level.

A Series of Enthalpically Optimized Docetaxel Analogues Exhibiting Enhanced Antitumor Activity and Water Solubility

A dual-purpose strategy aimed at enhancing the binding affinity for microtubules and improving the water solubility of docetaxel led to the design and synthesis of a series of C-2- and C-3'-modified analogues. Both aims were realized when the C-3' phenyl group present in docetaxel was replaced with a propargyl alcohol. The resulting compound, 3f, was able to overcome drug resistance in cultured P-gp-overexpressing tumor cells and showed greater activity than docetaxel against drug-resistant A2780/AD ovarian cancer xenografts in mice. In addition, the considerably lower hydrophobicity of 3f relative to both docetaxel and paclitaxel led to better aqueous solubility. A molecular model of tubulin-bound 3f revealed novel hydrogen-bonding interactions between the propargyl alcohol and the polar environment provided by the side chains of Ser236, Glu27, and Arg320.

Final 10-year results of the Breast International Group 2-98 phase III trial and the role of Ki67 in predicting benefit of adjuvant docetaxel in patients with oestrogen receptor positive breast cancer

AIM

Breast International Group (BIG) 2-98 is a randomised phase III trial that tested the effect of adding docetaxel, either in sequence to or in combination with anthracycline-based adjuvant chemotherapy, in women with node-positive breast cancer (BC). Here, we present the 10-year final trial safety and efficacy analyses. We also report an exploratory analysis on the predictive value of Ki67 for docetaxel efficacy, in the BIG 2-98 and using a pooled analysis of three other randomised trials.

PATIENTS AND METHODS

2887 patients were randomly assigned in a 2×2 trial design to one of four treatments. The primary objective was to evaluate the overall efficacy of docetaxel on disease free survival (DFS). Secondary objectives included comparisons of sequential docetaxel versus sequential control arm, safety and overall survival (OS). Ki67 expression was centrally evaluated by immunohistochemistry.

RESULTS

After a median follow-up of 10.1years, the addition of docetaxel did not significantly improve DFS or OS (hazard ratio (HR)=0.91, 95% confidence interval (CI)=0.81-1.04; P=0.16 and HR=0.88, 95% CI=0.76-1.03; P=0.11, respectively). Sequential docetaxel did not improve DFS compared to the sequential control arm (HR=0.86, 95% CI=0.72-1.03; P=0.10). In oestrogen receptor (ER)-positive tumours with Ki67⩾14%, the addition of docetaxel resulted in 5.4% improvement in 10-year OS (P=0.03, test for interaction=0.1). In a multivariate model, there was a trend for improved DFS and OS in ER-positive patients with high Ki67 and treated with docetaxel (HR=0.79, 95% CI=0.63-1.01; P=0.05 and HR=0.76, 95% CI=0.57-1.01; P=0.06, respectively). A pooled analysis of four randomised trials showed a benefit of taxanes in highly proliferative ER-positive disease but not in low proliferating tumours (interaction test P=0.01).

CONCLUSION

The DFS benefit previously demonstrated with sequential docetaxel is no longer observed at 10years. However, an exploratory analysis suggested a benefit of docetaxel in patients with highly proliferative ER-positive BC.

Pathologic complete response rates in triple-negative, HER2-positive, and hormone receptor-positive breast cancers after anthracycline-free neoadjuvant chemotherapy with carboplatin and paclitaxel with or without trastuzumab

BACKGROUND

Pathologic complete response (pCR) to neoadjuvant chemotherapy (NCT) is considered a surrogate for improved survival. Platinum-containing NCT, particularly in patients with HER2+ and triple-negative breast cancers (TNBC) may increase pCR rates.

METHODS

Tumor characteristics, pCR rates (no invasive disease in breast and lymph nodes), toxicities, and survival in patients who received carboplatin, a taxane, and trastuzumab (HER2+ disease) between April 2009 and December 2011, were reviewed.

RESULTS

Thirty eight patients (39 tumors) completed a median of 4 cycles of NCT. Eighteen of 39 (46%) tumors were HER2+, 8/18 (44%) responded with pCR; 13/18 HER2+ tumors were HR+ (72%) and 4/13 (31%) had a pCR. Ten of 39 (26%) tumors were TNBC; 6/10 (60%) had a pCR. At a median of 25-months no recurrences were observed in patients with pCR.

CONCLUSIONS

Prospective studies of anthracycline-free platinum-containing NCT are warranted in LABC patients with HER2+ and TNBC.

Paclitaxel/epigallocatechin gallate coloaded liposome: a synergistic delivery to control the invasiveness of MDA-MB-231 breast cancer cells

Matrix metalloproteinases (MMPs) have been investigated as a potential target for treating invasive breast cancers. The chemotherapy for breast cancer is often prescribed as a combination of drugs. The present study investigates a novel strategy of combining a MMP inhibitor, Epigallocatechin gallate (EGCG), along with an anticancer drug, Paclitaxel (PTX), in the form of a liposomal co-delivery system. The developed PTX/EGCG co-loaded liposomes showed an entrapment of 77.11±2.30% and 59.11±3.51% for PTX and EGCG, respectively. The in vitro efficacy of the liposomes was assessed by their ability to promote apoptosis and curtail cell invasion. On all parameters, namely cytotoxicity and caspase-3 activity that are indicators of apoptosis, and MMP-2 and - 9 inhibition and invasion assays that are indicators of cell invasion, the PTX/EGCG co-loaded liposomes showed better results than each of the individual drug loaded liposomes. These findings demonstrate the synergistic outcome of PTX/EGCG combination and indicate the suitability of PTX/EGCG co-loaded liposomes for the treatment of invasive breast cancer.

Gemcitabine in metastatic breast cancer

Gemcitabine is a pyrimidine antimetabolite which has shown activity in metastatic breast cancer both as a single agent, but also in various combination regimens. It is characterized by a unique mechanism of action which includes cytotoxic self-potentiation, masked DNA chain termination and potent inhibition of DNA repair. The clinical application of gemcitabine is supported by a favorable toxicity profile. In metastatic breast cancer, several Phase II trials document the activity of gemcitabine in pretreated and unpretreated patients. In a single Phase III trial performed in elderly patients not pretreated, gemcitabine was inferior to epirubicin. High activity has, however, been obtained by the combination of gemcitabine with taxanes such as paclitaxel or docetaxel. In a randomized trial performed in anthracycline-pretreated patients, the combined use of gemcitabine and paclitaxel induced a significant improvement not only of response rate and time to disease progression, but also caused a significant increase in quality of life and survival when compared with paclitaxel alone. The combination of gemcitabine with vinorelbine and cisplatin has been validated in numerous Phase II trials and promises reliable activity in anthracycline- and/or taxane-pretreated patients. Triple-agent regimens such as gemcitabine/epirubicin/paclitaxel provided consistently high response rates in Phase II trials, but failed to show superiority over the 5-fluorouracil/epirubicin/cyclophosphamide regimen in a randomized Phase III trial. Based on high response rates and pathological complete remission rates achieved by preoperative induction therapy with gemcitabine/epirubicin/taxane regimens, ongoing trials focus on the incorporation of gemcitabine into neoadjuvant and adjuvant regimens.

Taxane chemotherapy treatment for metastatic breast cancer

SUMMARY The taxanes, paclitaxel, docetaxel and nab-paclitaxel, are among the most active cytotoxic agents for treatment of breast cancer. Significant progress has been made in addressing taxane dose and schedule in both early-stage and metastatic disease. Several studies have clarified the role of retreatment with taxanes in recurrent breast cancer patients previously treated with taxane-containing regimens. In addition, the advent of nab-paclitaxel, designed to reduce allergic reactions and enhance drug delivery to tumor cells, has provided additional therapeutic options. This article summarizes the uses of taxanes in the treatment of metastatic breast cancer.

Weekly docetaxel in the treatment of metastatic breast cancer

Breast cancer is the most frequent tumor among women worldwide and is the second cause of cancer-related mortality in the US. Metastatic breast cancer (MBC) accounts for less than 10% of newly diagnosed breast cancer patients and about 30% of early breast cancer patients will develop recurrent, advanced, or metastatic disease. It remains an incurable illness and the primary goal of its management is palliative. Several agents are active for the first-line treatment of MBC. The taxanes, paclitaxel and docetaxel, represent the standard of care for the treatment of these patients. Among the various schedules, docetaxel can be administered weekly, achieving similar efficacy results with lower toxicity compared with conventional schedules. Weekly docetaxel (25–40 mg/m²) has been widely tested in several phase I and II studies both as a single agent and in multichemotherapy regimens, reaching overall response rates ranging from 26% and 86% or 20% and 73% with docetaxel alone or in combination, respectively, depending on doses, associations, and line of treatment. Overall, published data support the administration of weekly docetaxel for the treatment of MBC patients even if data from phase III randomized trials are still lacking.

Synthesis and preliminary biological evaluation of high-drug-load paclitaxel-antibody conjugates for tumor-targeted chemotherapy

The goal of this study was to design paclitaxel (PTX)-monoclonal antibody (mAb) prodrug conjugates (PTXMAbs) with the ability to deliver therapeutically significant doses of the drug to the tumor while avoiding the previously observed solubility limitations of conjugates with PTX:mAb molar ratios of >3. New PTX conjugates were synthesized using the discrete poly(ethylene glycol) (dPEG) as linkers. These compounds, PTX-L-Lys[(dPEG12)(3)-dPEG4]-dPEG6-NHS (9a and 9b, for L = GL or SX, respectively), were then conjugated to the antiepidermal growth factor receptor mAb, C225 at increasing PTX:C225 ratios, producing completely soluble conjugates. Unlike the earlier PTXMAbs, buffered solutions of these conjugates remained homogeneous for extended periods of time. Fluorescence-activated cell sorting (FACS) analysis indicated preserved immunogenicity of the conjugates at all four substitution ratios, while cytotoxicity studies in MDA-MB-468 breast cancer cells indicated preservation of drug cytotoxicity. These conjugates may have potential in the development of high-drug-load tumor-targeting taxanes.

Dose-escalation phase I study in metastatic breast cancer patients with combination of paclitaxel and tegafur·uracil

The study present the results of the dose-setting study of concomitant weekly administration of paclitaxel and tegafur·uracil (UFT) for metastatic breast cancer. Eligible patients who entered the study underwent two or more courses of weekly paclitaxel + UFT therapy as the protocol therapy. The initial dose (level 1) was paclitaxel, 80 mg/m(2) and UFT, 400 mg/day. At level 2, paclitaxel remained the same, but UFT was increased to 600 mg/day. At level 3, only paclitaxel was increased to 90 mg/m(2). Twelve patients were enrolled in this study between September 2000 and September 2002. Three patients were assigned to level 1. Grade 3 liver dysfunction (increased aspartate aminotransferase and alanine aminotransferase) was noted in one patient and grade 4 neutropenia was noted in one patient, showing that dose-limiting toxicity was detected in 2/3 patients. In accordance with the protocol, UFT was fixed at 400 mg/day and paclitaxel was decreased to 60 mg/m(2) at level -1, and then increased to 70 mg/m(2) at level 0. The overall effective rate after completion of two courses was 33% (3/9) including one case of complete response and two cases of partial responses. The remaining patients presented with stable diseases and no patient had progressive disease. In this study, weekly paclitaxel with concomitant UFT was administered. The recommended doses of paclitaxel and UFT were determined to be 70 mg/m(2) and 400 mg/day, respectively. As the toxicity profile shows, the highest toxicity level of this regimen was neutropenia and liver dysfunction, and dose-limiting toxicity was neutropenia.

Paclitaxel combined with ifosfamide in anthracycline- and docetaxel-pretreated metastatic breast cancer: activity independence of prior docetaxel resistance

BACKGROUND

We evaluated the efficacy and tolerability of combined paclitaxel and ifosfamide in anthracycline- and docetaxel-pretreated metastatic breast cancer (MBC).

METHODS

Patients received paclitaxel (175 mg/m(2) i.v. in a 3-h infusion) on day 1 and ifosfamide (1.5 g/m(2) i.v. in a 15-min infusion) on days 1-3, every 3 weeks for a maximum of nine cycles. The tumor response was assessed every two cycles.

RESULTS

We enrolled 34 patients with a median age of 50 years. Thirty patients had visceral metastases. Anthracycline- and docetaxel-based chemotherapy had previously been administered to 18/13 and 13/21 patients, respectively, in (neo)adjuvant/metastatic settings. Three patients had not previously received anthracycline due to abnormal cardiac functions. A total of 174 cycles of chemotherapy were delivered with a median of six cycles. The response rate under the intent-to-treat analysis was 23.5% (all partial responses) with a median response duration of 14 months. The disease control rate was 70.6%. The median progression-free and overall survival were 5.9 and 8.5 months, respectively. There was no apparent relationship between activity and prior docetaxel resistance. The incidence of grade III/IV neutropenia was 46.6% (81 of 174 cycles) with febrile neutropenia of only 1.7%. Major grade III/IV non-hematological toxicities included peripheral neuropathy (6 of 34 patients) and infection (4 of 34 patients). There were no treatment-related deaths.

CONCLUSION

Paclitaxel combined with ifosfamide was effective and tolerable in anthracycline-/docetaxel-pretreated MBC. Overcoming docetaxel resistance by using paclitaxel in combination with ifosfamide needs to be addressed through further investigation.

Therapeutic options for metastatic breast cancer

Metastatic breast cancer (MBC) remains an incurable disease despite ongoing therapeutic advances. Recently there has been progress extending the range of available cytotoxic chemotherapy drugs and optimizing their scheduling. In addition, a greater understanding of tumor biology has led to the development of a number of targeted therapies. Several of these newer agents, such as trastuzumab, lapatinib and bevacizumab, have demonstrated activity in combination with chemotherapy and have improved the prognosis of patients with MBC. We hope that further progress elucidating the pathophysiology and biology of MBC will continue to lead to corresponding advances in treatment.

Salvage therapy of pretreated advanced breast cancer with bevacizumab and paclitaxel every two weeks: a retrospective case review study

Background

Targeting angiogenesis is nowadays one of the most promising approaches for breast cancer. Bevacizumab (BEV), a VEGF-trap monoclonal antibody, was recently approved in combination with paclitaxel (PAC) for the first line treatment of advanced breast cancer (ABC). The activity of this combination in pretreated patients is not known.

Methods

Patients with pretreated ABC and progressive disease received BEV 10 mg/kg with PAC 135 mg/m² every two weeks for six months and then maintenance with BEV 15 mg/kg every three weeks until progression. This regimen was chosen for better patient convenience, while maintaining the same dose intensity for both drugs.

Results

42 patients were reviewed retrospectively (41 f, 1 m, mean age 57 years). Overall response rate was 35.7%. Stable disease was observed in 45.2% of patients, whereas 14.3% of patients progressed. The median overall survival was greater than 20 months, with a one year rate of 83.4%. The median progression free survival was 12.1 months, with a one year rate of 51.8%. Toxicity was in general acceptable.

Conclusion

This biweekly BEV/PAC combination seems to be active with acceptable toxicity in pretreated ABC with an advantage over the weekly regimen regarding quality of life and preservation of resources.

Frequent pathologic complete responses in aggressive stages II to III breast cancers with every-4-week carboplatin and weekly paclitaxel with or without trastuzumab: a Brown University Oncology Group Study

PURPOSE

To evaluate the efficacy and safety of neoadjuvant carboplatin and weekly paclitaxel +/- weekly trastuzumab in resectable and locally advanced breast cancer.

PATIENTS AND METHODS

Women with stages IIA to IIIB disease received carboplatin dosed by six times the area under the curve every 4 weeks and paclitaxel 80 mg/m(2) weekly for 16 weeks, and weekly trastuzumab was added for human epidermal growth factor receptor 2 (HER2) -positive status. The primary end point was the pathologic complete response (pCR) rate, defined as the absence of invasive disease in the breast and axillary nodes. Postoperative therapies were at the discretion of the treating physicians.

RESULTS

Fifty-five patients were enrolled, and of these 43 had resectable disease. The median age was 54 years (range, 31 to 74 years). Treatment was well tolerated; there were no episodes of febrile neutropenia or grade 4 thrombocytopenia, and there were only two instances of grade 3 peripheral neuropathy. Overall, the pCR rate was 45%. The pCR rate was 43% (95% CI, 28% to 58%) in patients with resectable disease. Higher pCR rates occurred in patients with HER2-positive tumors (76% v 31% for HER2-negative tumors; P = .003), with estrogen receptor (ER) -negative tumors (75% v 27% for ER-positive tumors; P = .001), or with triple-negative tumors (67% v 12% ER-positive and HER2-negative tumors; P = .002). At a median of 28 months postoperation, recurrence-free survival (RFS) was 88.7%. If patients with ER-positive and HER2-negative tumors are excluded from analysis, patients who achieved a pCR were less likely to experience disease recurrence (RFS, 86%) than those who did not achieve a pCR (RFS, 75%).

CONCLUSION

Neoadjuvant carboplatin and weekly paclitaxel +/- trastuzumab achieve high pCR rates in patients with HER2-positive and triple-negative disease without exposure to an anthracycline. Preliminary RFS results are encouraging but are likely influenced by adjuvant therapy received. Additional study of this regimen in high-risk patients is warranted.

Phase II Study of Gemcitabine Plus Paclitaxel in Metastatic Breast Cancer Patients with Prior Anthracycline Exposure

Chemotherapy provides palliation and modest prolongation of symptom-free survival in metastatic breast cancer. Taxane containing regimens are commonly considered to be among the initials in metastatic setting due to earlier use of anthracyclines in the course of breast cancer. Therefore, we conducted this Phase II study to assess efficacy and safety of gemcitabine plus paclitaxel (GT) combination therapy in anthracycline pretreated metastatic first-line setting.

PATIENTS AND METHODS

The study enrolled 26 women with pathologically confirmed and measurable metastatic breast cancer who were previously treated with anthracycline but no prior chemotherapy for metastatic disease. Twenty six and twenty four patients were eligible for toxicity and efficacy evaluations respectively. Mean age was 47.3 years and median ECOG performance status was 0. Twenty patients (76.9 percent) had visceral metastases, most commonly located in liver and lung. Treatment schedule was as follows: paclitaxel 175 mg/m2 was administered intravenously in 3 hours on Day 1 and gemcitabine 1000 mg/m2 was administered intravenously in 30 minutes on Day 1 after paclitaxel application, and on Day 8 every 21 days.

RESULTS

Objective response rate was 41.7 percent (95 percent CI: 21.9-61.4) with 16.7 percent (95 percent CI: 1.7-31.6 percent) CR, and 25.0 percent (95 percent CI: 7.6-42.3 percent) PR. Median time to progression and overall survival were 9.6 and 14.5 months, respectively. Grade 3-4 toxicity was observed in 34.6 percent (9) patients. Treatment of two patients was discontinued due to toxicity, consisting of Grade 3 hypersensitivity reactions and Grade 4 infections in one patient each. Dose reductions due to myelotoxicity were performed in 4 (15.3 percent) patients. Hematologic toxicities were generally manageable with appropriate dose modifications and supportive care.

CONCLUSION

Gemcitabine and paclitaxel combination regimen is effective and has manageable toxicity profile as first line metastatic setting.

Paclitaxel as a first-line chemotherapy for Japanese women with advanced or recurrent breast cancer: a multi-institutional practice-based study by the Kyushu Breast Cancer Study Group (KBC-SG)

BACKGROUND

Anthracycline-containing chemotherapy has represented the standard treatment for advanced breast cancer. However, it is sometimes difficult to continue it because of its cumulative cardiac toxicity, and the benefit of adding anthracyclines to the chemotherapy regimen is confined to HER2-overexpressed breast cancer. A non-anthracycline-based novel therapy is necessary to improve the survival and reduce the toxicity.

METHODS

We evaluated the tumor response and adverse events of a first-line paclitaxel therapy in advanced or recurrent breast cancer in a variety of practice settings. Patients were to receive paclitaxel tri-weekly (175 mg/m(2)), bi-weekly (120 mg/m(2)) or weekly (80 mg/m(2)) until disease progression or toxicity precluded further treatment. Tumor response and toxicities were evaluated.

RESULTS

Thirty-three patients received a total of 191 cycles (median 5, range 2-19). All patients completed at least two cycles. In 30 patients who were evaluable for response, there were 16 overall responses [53%, 95% confidence interval (CI) 34-72%], including 5 complete responses (17%, 95% CI 3-31%). The median progression-free survival and overall survival were 16 (95% CI 9-24) months and 29 (95% CI 24-36) months, respectively. Overall treatment was well tolerated, and no myelosuppression >grade 3 was reported during this study. A grade 3 dyspnea was noted in one patient, but it recovered spontaneously, and subsequent administration of paclitaxel was successfully given with no specific treatment. No other toxicity greater than grade 3 was demonstrated.

CONCLUSION

Paclitaxel as a first-line therapy at this dose and schedule is an effective and well-tolerated treatment regimen in Japanese patients with advanced or recurrent breast cancer.

Phase I trial of weekly docetaxel, weekly doxorubicin, daily oral cyclophosphamide, and G-CSF (ConTAC regimen) in advanced malignancies

PURPOSE

This was a phase I study evaluating the dose limiting toxicity (DLT) and the maximum tolerated dose (MTD) of weekly docetaxel, doxorubicin and daily oral cyclophosphamide with G-CSF support (ConTAC regimen).

PATIENTS AND METHODS

Cohorts of 3-6 patients with advanced breast or other solid malignancies were entered at subsequently higher dose levels until dose-limiting toxicities (DLT) were noted in 2 or more patients per dose level during the first 6 weeks of therapy. This study escalated dosages of docetaxel and doxorubicin simultaneously, while the dose of oral cyclophosphamide was fixed at 60 mg/m(2) daily.

RESULTS

Sixteen patients were enrolled. Grade 3-4 adverse events during the first 6 weeks of treatment were neutropenia (n = 1 at dose level #1 and n = 3 at dose level #4), anemia (n = 2 at dose levels 1 and 4), and nausea/vomiting (n = 1 at dose level #4). After 6 weeks of therapy, grade 3-4 toxicities included anemia (n = 3), neutropenia (n = 7), Hand-Foot syndrome (n = 2) and grade 3 cystitis and pneumonia (n = 1 at dose level #4). Five patients with advanced breast cancer and 1 patient with metastatic lung cancer responded to the chemotherapy.

CONCLUSIONS

Grade 4 neutropenia was the DLT. The MTD, was established at dose level #3 (doxorubicin at 25 mg/m(2) and docetaxel at 25 mg/m(2) weekly with oral cyclophosphamide dose of 60 mg/m(2) daily). Myelosuppression at that dose level was moderate with G-CSF given concurrently.

The diagnosis and management of cardiovascular disease in cancer patients

Cardiovascular disease is commonly found in cancer patients. The co-existence of heart disease and cancer in a patient often complicates treatment, because therapy for one disease may negatively affect the outcome of the other disease. In addition, guidelines for the treatment of cardiovascular disease are often based on studies, which exclude patients who have cancer. In this review we will discuss the diagnosis and management of cardiovascular disease in cancer patients. We will focus on cancer-related causes of cardiovascular disease and special treatment options for cardiovascular disease in cancer patients. The cardiac complications of cancer therapy will be discussed according to common syndromes: left ventricular dysfunction, myocardial ischemia, blood pressure changes, thromboembolism, bradyarrhythmias, and prolonged QT interval.

Overview of resistance to systemic therapy in patients with breast cancer

Breast cancer is the most common cancer and the second leading cause of cancer death in American women. It was the second most common cancer in the world in 2002, with more than 1 million new cases. Despite advances in early detection and the understanding of the molecular bases of breast cancer biology, about 30% of patients with early-stage breast cancer have recurrent disease. To offer more effective and less toxic treatment, selecting therapies requires considering the patient and the clinical and molecular characteristics of the tumor. Systemic treatment of breast cancer includes cytotoxic, hormonal, and immunotherapeutic agents. These medications are used in the adjuvant, neoadjuvant, and metastatic settings. In general, systemic agents are active at the beginning of therapy in 90% of primary breast cancers and 50% of metastases. However, after a variable period of time, progression occurs. At that point, resistance to therapy is not only common but expected. Herein we review general mechanisms of drug resistance, including multidrug resistance by P-glycoprotein and the multidrug resistance protein family in association with specific agents and their metabolism, emergence of refractory tumors associated with multiple resistance mechanisms, and resistance factors unique to host-tumor-drug interactions. Important anticancer agents specific to breast cancer are described. Breast cancer is the most common type of cancer and the second leading cause of cancer death in American women. In 2002, 209,995 new cases of breast cancer were registered, and 42,913 patients died of it. In 5 years, the annual prevalence of breast cancer will reach 968,731 cases in the United States. World wide, the problem is just as significant, as breast cancer is the most frequent cancer after nonmelanoma skin cancer, with more than 1 million new cases in 2002 and an expected annual prevalence of more than 4.4 million in 5 years. Breast cancer treatment currently requires the joint efforts of a multidisciplinary team. The alternatives for treatment are constantly expanding. With the use of new effective chemotherapy, hormone therapy, and biological agents and with information regarding more effective ways to integrate systemic therapy, surgery, and radiation therapy, elaborating an appropriate treatment plan is becoming more complex. Developing such a plan should be based on knowledge of the benefits and potential acute and late toxic effects of each of the therapy regimens. Despite advances in early detection and understanding of the molecular bases of breast cancer biology, approximately 30% of all patients with early-stage breast cancer have recurrent disease, which is metastatic in most cases. The rates of local and systemic recurrence vary within different series, but in general, distant recurrences are dominant, strengthening the hypothesis that breast cancer is a systemic disease from presentation. On the other hand, local recurrence may signal a posterior systemic relapse in a considerable number of patients within 2 to 5 years after completion of treatment. To offer better treatment with increased efficacy and low toxicity, selecting therapies based on the patient and the clinical and molecular characteristics of the tumor is necessary. Consideration of these factors should be incorporated in clinical practice after appropriate validation studies are performed to avoid confounding results, making them true prognostic and predictive factors. A prognostic factor is a measurable clinical or biological characteristic associated with a disease-free or overall survival period in the absence of adjuvant therapy, whereas a predictive factor is any measurable characteristic associated with a response or lack of a response to a specific treatment. The main prognostic factors associated with breast cancer are the number of lymph nodes involved, tumor size, histological grade, and hormone receptor status, the first two of which are the basis for the AJCC staging system. The sixth edition of the American Joint Committee on Cancer staging system allows better prediction of prognosis by stage. However, after determining the stage, histological grade, and hormone receptor status, the tumor can behave in an unexpected manner, and the prognosis can vary. Other prognostic and predictive factors have been studied in an effort to explain this phenomenon, some of which are more relevant than others: HER-2/neu gene amplification and protein expression, expression of other members of the epithelial growth factor receptor family, S phase fraction, DNA ploidy, p53 gene mutations, cyclin E, p27 dysregulation, the presence of tumor cells in the circulation or bone marrow, and perineural and lymphovascular space invasion. Systemic treatment of breast cancer includes the use of cytotoxic, hormonal, and immunotherapeutic agents. All of these agents are used in the adjuvant, neoadjuvant, and metastatic setting. Adjuvant systemic therapy is used in patients after they undergo primary surgical resection of their breast tumor and axillary nodes and who have a significant risk of systemic recurrence. Multiple studies have demonstrated that adjuvant therapy for early-stage breast cancer produces a 23% or greater improvement in disease-free survival and a 15% or greater increase in overall survival rates. Recommendations for the use of adjuvant therapy are based on the individual patient's risk and the balance between absolute benefit and toxicity. Anthracycline-based regimens are preferred, and the addition of taxanes increases the survival rate in patients with lymph node-positive disease. Adjuvant hormone therapy accounts for almost two thirds of the benefit of adjuvant therapy overall in patients with hormone-receptor-positive breast cancer. Tamoxifen is considered the standard of care in premenopausal patients. In comparison, the aromatase inhibitor anastrozole has been proven to be superior to tamoxifen in postmenopausal patients with early-stage breast cancer. The adjuvant use of monoclonal antibodies and targeted therapies other than hormone therapy is being studied. Interestingly, some patients have an early recurrence even though they have a tumor with good prognostic features and at a favorable stage. These recurrences have been explained by the existence of certain cellular characteristics at the molecular level that make the tumor cells resistant to therapy. Selection of resistant cell clones of micrometastatic disease has also been proposed as an explanation for these events. Neoadjuvant systemic therapy, which is the standard of care for patients with locally advanced and inflammatory breast cancer, is becoming more popular. It reduces the tumor volume, thus increasing the possibility of breast conservation, and at the same time allows identification of in vivo tumor sensitivity to different agents. The pathological response to neoadj uvant systemic therapy in the breast and lymph nodes correlates with patient survival. Use of this treatment modality produces survival rates identical to those obtained with the standard adjuvant approach. The rates of pathological complete response (pCR) to neoadjuvant systemic therapy vary according to the regimen used, ranging from 6% to 15% with anthracycline-based regimens to almost 30% with the addition of a noncross-resistant agent such as a taxane. In one study, the addition of neoadjuvant trastuzumab in patients with HER-2-positive breast tumors increased the pCR rate to 65%. Primary hormone therapy has also been used in the neoadjuvant systemic setting. Although the pCR rates with this therapy are low, it significantly increases breast conservation. Currently, neoadjuvant systemic therapy is an important tool in not only assessing tumor response to an agent but also studying the mechanisms of action of the agent and its effects at the cellular level. However, no tumor response is observed in some cases despite the use of appropriate therapy. The tumor continues growing during treatment in such cases, a phenomenon called primary resistance to therapy. The use of palliative systemic therapy for metastatic breast cancer is challenging. Five percent of newly diagnosed cases of breast cancer are metastatic, and 30% of treated patients have a systemic recurrence. Once metastatic disease develops, the possibility of a cure is very limited or practically nonexistent. In this heterogeneous group of patients, the 5-year survival rate is 20%, and the median survival duration varies from 12 to 24 months. In this setting, breast cancer has multiple clinical presentations, and the therapy for it should be chosen according to the patient's tumor characteristics, previous treatment, and performance status with the goal of improving survival without compromising quality of life. Treatment resistance is most commonly seen in such patients. They initially may have a response to different agents, but the responses are not sustained, and, in general, the rates of response to subsequent agents are lower. Table 1 summarizes metastatic breast cancer response rates to single-agent systemic therapy.

Weekly epirubicin and paclitaxel with granulocyte colony-stimulating factor support in previously untreated metastatic breast cancer patients: a phase II study

We conducted a phase II study to determine the activity and tolerability of weekly epirubicin-paclitaxel and granulocyte colony-stimulating factor in breast cancer patients untreated for metastatic disease. The phase II study was designed following the Simon optimal-two stage method. Patients received epirubicin 25 mg/m and paclitaxel 80 mg/m every week, and granulocyte colony-stimulating factor on days 2 and 4 for 24 consecutive weeks in the absence of progression. From 1999 to 2004, 53 patients entered the study; 1093 weekly courses were delivered, with a median number of cycles of 22. Patients received a median relative dose intensity of 94%. No hematological grade 3-4 toxicities were observed. One patient had one episode of grade 3 mucositis and two patients (3.8%) suffered grade 2 asthenia. Eight patients (15.1%) experienced grade 2 neutropenia, grade 2 anemia was registered in seven patients (13.2%). No cardiotoxicity was observed. Ten out of 53 patients (18.9, 95% confidence interval 8.3, 29.4%) showed a complete response, whereas 28 (52.8, 95% confidence interval 39.4, 66.3%) had a partial response, with an overall response rate of 71.7% (95% confidence interval 59.6, 83.8%). In addition, 14 patients (26.4%) had stable disease. Median time to progression was 12 months (95% confidence interval 7, 17). Median response duration was 14 months (range 3-60). The 1-, 3- and 5-year survival rates were 90.1, 68.0 and 56.6%, respectively. In untreated metastatic breast cancer patients, the weekly administration of epirubicin and paclitaxel with granulocyte colony-stimulating factor support seems to be extremely tolerable and active, and deserves further investigation into a phase III trial.

Survival Differences Observed in Metastatic Breast Cancer Patients Treated With Capecitabine When Compared With Vinorelbine After Pretreatment With Anthracycline and Taxane

OBJECTIVES

The optimal treatment of metastatic breast cancer patients previously treated with anthracycline and taxane is unknown. Common therapeutic alternatives include capecitabine and vinorelbine. This retrospective chart review compares overall survival following treatment with capecitabine, vinorelbine, or both agents sequentially in this group of women.

PATIENTS AND METHODS

Electronic patient records and charts of patients who received anthracycline and taxane-based chemotherapy and subsequently received capecitabine and/or vinorelbine at 3 Canadian cancer centers, between November 1994 and June 2003, were retrospectively reviewed.

RESULTS

A total of 140 patients met the study eligibility criteria: 45 patients received vinorelbine as a single agent and 68 received capecitabine as a single agent. The median duration of therapy was 64 days with vinorelbine and 129 days with capecitabine (P = 0.0012). Median overall survival was 102 days for the vinorelbine group and 188 days for the capecitabine group (P < 0.0001). Survival at 1 year was 15.6% for the vinorelbine group and 28.4% for the capecitabine group (P = 0.017). Twenty-seven patients received both agents sequentially; and in this group, the median duration of therapy was 110 days (87 days with vinorelbine and 138 days with capecitabine), and the median overall survival was 390 days.

CONCLUSIONS

This exploratory analysis suggests that patients with tumors previously treated with both anthracycline and taxane can still obtain significant survival benefit from further chemotherapy. The results indicate that capecitabine may be superior to vinorelbine in this setting.

Multicenter phase II trial of Genexol-PM, a Cremophor-free, polymeric micelle formulation of paclitaxel, in patients with metastatic breast cancer

Genexol-PM is a novel Cremophor EL-free polymeric micelle formulation of paclitaxel. This single arm, multicenter phase II study was designed to evaluate the efficacy and safety of Genexol-PM in patients with histologically confirmed metastatic breast cancer (MBC). Forty-one women received Genexol-PM by intravenous infusion at 300 mg/m2 over 3 h every 3 weeks without premedication until disease progression or intolerability. A total of 331 chemotherapy cycles were administered, with a median of 8 cycles per patient (range, 1-16). Overall response rate was 58.5% (95% CI: 43.5-72.3) with 5 complete responses and 19 partial responses. Thirty-seven patients who received Genexol-PM as a first-line therapy for their metastatic disease showed a response rate of 59.5% (95% CI: 43.5-73.7), and two responses were reported in four patients treated in the second-line setting for their metastatic disease. The median time to progression (TTP) for all patients was 9.0 months (range, 1.0-17.0+ months). Grade 3 non-hematologic toxicities included sensory peripheral neuropathy (51.2%), and myalgia (2.4%). Eight patients (19.5%) experienced hypersensitivity reactions, with grade 3 in two patients. Hematologic toxicities were grade 3 and 4 neutropenia (51.2 and 17.1%, respectively), and grade 1 and 2 thrombocytopenia (22.0%). Notably, no febrile neutropenia was observed. Genexol-PM appears a promising new paclitaxel in view of significant efficacies. Further trials with different dosing schedules, durations of delivery, or in combination with other drugs are warranted.

ProANP and NT-proBNP levels to prospectively assess cardiac function in breast cancer patients treated with cardiotoxic chemotherapy

BACKGROUND

Cardiac function impairment is a known side effect of epirubicin-based chemotherapy. Activation of natriuretic peptides is demonstrated in patients with heart failure.

AIMS

To identify prospectively the cardiotoxic profile of epirubicin-based chemotherapy in breast cancer patients and to evaluate the sensitivity of proANP and NT-proBNP as early biochemical markers of cardiac dysfunction.

METHODS

Forty cancer patients divided in two nonrandomized groups received either epirubicin and paclitaxel (Group A, n=26) or mitoxantrone and docetaxel (Group B, n=14). Control groups, Group C (n=13) and Group D (n=20), consisted of female patients with heart failure and healthy women respectively. Natriuretic peptides and LVEF were determined in all patients.

RESULTS

A statistically significant difference was recorded regarding LVEF before and after treatment in Group A patients (p=0.0001). Three patients had a significant LVEF decline between 10% and 18% from baseline values, while three reached an LVEF value below 50%. All of them presented an increase in proANP and NT-proBNP values (mean increase 270.31+/-124 fmol/ml and 303.57+/-108 fmol/ml, respectively). A significant correlation between the increase in plasma proANP (r=0.8, p<0.0001), as well as NT-proBNP (r=0.7, p<0.0001) and the decrease in LVEF was observed. Regarding Group A, levels of proANP increased from 192.25 fmol/ml before treatment to 287.84 fmol/ml after treatment (p=0.0001), whereas NT-proBNP increased from 152.50 to 242 fmol/ml (p<0.0001) respectively. During follow up, two Group A patients developed congestive heart failure twelve and fourteen months after the completion of chemotherapy respectively. A significant LVEF decline was recorded in both patients during the episode. Regarding Group B, no statistically significant differences were demonstrated.

CONCLUSION

ProANP and NT-proBNP levels might be used as reliable and sensitive markers in the detection of early cardiac impairment caused by epirubicin-based chemotherapy.

Taxanes in breast cancer: An update

Over the past decade the taxanes have proved to be fundamental in the treatment of breast cancer. Initially found to have efficacy in metastatic breast cancer, the taxanes are now vital components in the treatment of early-stage disease, in which their addition to adjuvant treatment of early breast cancer has been shown to improve overall survival. In addition, the taxanes have demonstrated a role in first-line therapy for metastatic disease, with some of the highest efficacy of any class of chemotherapy. Targeted therapies in combination with the taxanes have further improved survival for both early and metastatic disease. New formulations of taxanes may both improve antitumor activity and reduce toxicity.

Salvage chemotherapy with gemcitabine and oxaliplatin in heavily pretreated patients with metastatic breast cancer: a multicenter phase II study

PURPOSE

It was the aim of this study to evaluate the activity and tolerance of gemcitabine and oxaliplatin in pretreated metastatic breast cancer patients.

METHODS

Thirty-one patients who had disease relapse or progression after completion of an anthracycline- and/or taxane-based front-line regimen were treated with gemcitabine 1,500 mg/m(2) on days 1 and 8 as a 30-min intravenous infusion and oxaliplatin 130 mg/m(2) on day 8 as a 4-hour intravenous infusion, in cycles of 21 days.

RESULTS

Complete response occurred in 1 patient (3%) and partial response in 4 patients (13%) (overall response rate 16%; 95% confidence interval 3.2-29.1). Nine patients (29%) had stable disease and 17 (55%) progressive disease. Three partial responses (13%) were achieved among 23 patients receiving the regimen as third-line treatment. The median duration of response was 6 months (range 3-44.8), the median time to tumor progression 4.6 months (range 0.8-43.8), and the median survival 14.4 months (range 2.1-44.8). Grade 3 and 4 neutropenia occurred in 14 patients (45%), grade 3 and 4 thrombocytopenia in 6 patients (20%), and grade 2 and 3 asthenia in 4 patients (13%). There was no episode of febrile neutropenia.

CONCLUSION

The gemcitabine-oxaliplatin combination is a relatively active and well-tolerated salvage regimen in patients with heavily pretreated metastatic breast cancer.

The role of taxanes in the treatment of breast cancer

Among the novel chemotherapeutic agents introduced in the last decade, the taxanes have emerged as the most powerful group of compounds, and results available so far confirm that they will be remembered in the future as the breast cancer chemotherapy of the 1990s. Two taxanes are available (paclitaxel and docetaxel) and they share some characteristics, although they do have some significant differences both in terms of their preclinical profile and, most importantly, their clinical characteristics. There are three main clinical differences: different efficacy-toxicity ratio in relation to dose and schedule; different integrability in anthracycline- and taxane-containing regimens, secondary to differences in pharmacokinetic interactions with anthracyclines; and different level of synergism between each taxane and trastuzumab. In clinical practice, the taxanes are now standard therapy in metastatic breast cancer. Their role as monochemotherapy or in combination with anthracyclines in advanced breast cancer has suggested their potential therapeutic impact in the treatment of patients with early breast cancer. Recent results in the adjuvant setting show that taxanes, used either in combination or in sequential therapy, possess the capability to induce significant improvements, in particular in terms of survival; thus confirming the positive impact of taxanes on the natural history of breast cancer. However, further results of all completed or ongoing Phase III trials in the early setting will help define the optimal use of taxanes and maximise the induced benefits for breast cancer patients.

First line chemotherapy of metastatic breast cancer

In the last 20-30 years the approach to metastatic breast cancer by chemotherapy has been largely studied. Anthracyclines, taxanes and, more recently, capecitabine and gemcitabine represent the breakthrough of treatment. In the next future the combination of chemotherapy and target therapy will be considered more frequently.

Sequential preoperative or postoperative docetaxel added to preoperative doxorubicin plus cyclophosphamide for operable breast cancer:National Surgical Adjuvant Breast and Bowel Project Protocol B-27

PURPOSE

This study was designed to determine the effect of adding docetaxel (T) to preoperative doxorubicin and cyclophosphamide (AC) on breast cancer response rates and disease-free survival (DFS) and overall survival (OS).

PATIENTS AND METHODS

Women with operable breast cancer (N = 2,411) were randomly assigned to receive preoperative AC followed by surgery, AC followed by T and surgery, or AC followed by surgery and then T. Tamoxifen was initiated concurrently with chemotherapy. Median time on study for 2,404 patients with follow-up was 77.9 months.

RESULTS

Addition of T to AC did not significantly impact DFS or OS. There were trends toward improved DFS with addition of T. The addition of T reduced the incidence of local recurrences as first events (P = .0034). Preoperative T, but not postoperative T, significantly improved DFS in patients who had a clinical partial response after AC (hazard ratio [HR] = 0.71; 95% CI, 0.55 to 0.91; P = .007). Pathologic complete response, which was doubled by addition of preoperative T, was a significant predictor of OS regardless of treatment (HR = 0.33; 95% CI, 0.23 to 0.47; P < .0001). Pathologic nodal status after chemotherapy was a significant predictor of OS (P < .0001).

CONCLUSION

The addition of preoperative or postoperative T after preoperative AC did not significantly affect OS, slightly improved DFS, and decreased the incidence of local recurrences. The sample size of this study was not sufficient to yield significance for the moderate DFS improvement. Concurrent use of tamoxifen may have limited the impact of adding T.

Weekly paclitaxel, 5-fluorouracil and folinic acid with granulocyte colony-stimulating factor support in metastatic breast cancer patients: a phase II study

We conducted a phase II study to determine the activity and tolerability of weekly paclitaxel, 5-fluorouracil (5-FU) and folinic acid plus granulocyte colony-stimulating factor (G-CSF) support in anthracycline-pre-treated or -resistant metastatic breast cancer patients. The phase II study was designed following the Simon optimal-two stage method. Patients received paclitaxel 80 mg/m, folinic acid 10 mg/m and bolus infusion of 5-FU 300 mg/m every week plus G-CSF on day 3 for 24 consecutive weeks in the absence of disease progression. From May 1998 to May 2000, 51 patients entered the study. Patients received a median relative dose intensity of 97.5% (range 81-100%). No severe toxicities were observed. Seven patients (14%) experienced neutropenia grade 2. Seven patients (14%) experienced grade 2 anemia. Two patients (4%) experienced severe asthenia. Three out of 50 evaluable patients [6%, 95% confidence interval (CI) 2-12.6%] showed a complete response, whereas 23 (46%, 95% CI 32.2-59.8%) had a partial response, with an overall response rate of 52% (95% CI 38.2-65.8%). In addition, eight patients (15.7%) had stable disease. In the 13 patients untreated for metastatic disease, the overall response rate was 92.3% (CI 77.8-100), with one complete response and 11 partial responses (84.6% CI 65-100%). In the whole group, the median time to progression and overall survival were 8 (range 1-18) and 14 months (95% CI 11-17), respectively. Thus, in metastatic breast cancer patients pre-treated with anthracyclines, the weekly administration of paclitaxel, 5-FU and folinic acid with G-CSF support seems to be extremely tolerable and active.

Role of Gemcitabine in Breast Cancer Management: An Update

Anthracyclines and the taxanes are now used earlier in the course of therapy for metastatic breast cancer, and increasingly as part of adjuvant treatment. Accordingly, novel therapies are warranted, including alternatives to anthracyclines and combination strategies in the setting of disease resistance to or disease progression after anthracycline and taxane therapy. Gemcitabine is part of this strategy. The gemcitabine/paclitaxel combination has emerged as part of a new standard of combination therapy for advanced breast cancer, based on phase III data showing superiority of this combination over paclitaxel alone in the first-line therapy setting. Gemcitabine alone, or in combination with paclitaxel and other agents, is also undergoing evaluation in other settings including the refractory metastatic setting, as part of management of patients with HER2-positive disease, and also as part of adjuvant therapy for breast cancer.

Weekly administration of docetaxel and paclitaxel in metastatic or advanced breast cancer

The taxanes docetaxel (Taxotere; Aventis Pharmaceuticals Inc., Bridgewater, NJ, http://www.aventispharma-us.com) and paclitaxel (Taxol; Bristol-Myers Squibb, Princeton, NJ, http://www.bms.com) have significant clinical activity in metastatic breast cancer. A number of clinical trials have evaluated the tolerability and efficacy of weekly taxane administration to optimize the benefit-to-risk ratio in metastatic breast cancer. Single-agent studies with docetaxel and paclitaxel in metastatic breast cancer show clinically significant antitumor activity even in advanced, heavily pretreated, resistant, and/or refractory disease. This activity is also evident with taxane-based combination regimens. Severe hematologic and nonhematologic toxicities are infrequent, with other toxicities noted based on the dose and weekly regimen selected. Weekly docetaxel and paclitaxel regimens represent valuable therapeutic options for women with metastatic breast cancer and have entered evaluation as part of adjuvant therapy for this disease.

First-line therapy with gemcitabine and paclitaxel in locally, recurrent or metastatic breast cancer: a phase II study

Background

This phase II study evaluated the efficacy and safety of gemcitabine (G) plus paclitaxel (T) as first-line therapy in recurrent or metastatic breast cancer.

Methods

Patients with locally, recurrent or metastatic breast cancer and no prior chemotherapy for metastatic disease received G 1200 mg/m² on days 1 and 8, and T 175 mg/m² on day 1 (before G) every 21 days for a maximum of 10 cycles.

Results

Forty patients, 39 metastatic breast cancer and 1 locally-advanced disease, were enrolled. Their median age was 61.5 years, and 85% had a World Health Organization performance status (PS) of 0 or 1. Poor prognostic factors at baseline included visceral involvement (87.5%) and ≥2 metastatic sites (70%). Also, 27 (67.5%) patients had prior adjuvant chemotherapy, 25 of which had prior anthracyclines. A total of 220 cycles (median 6; range, 1–10) were administered. Of the 40 enrolled patients, 2 had complete response and 12 partial response, for an overall response rate of 35.0% for intent-to-treat population. Among 35 patients evaluable for efficacy the response rate was 40%. Additional 14 patients had stable disease, and 7 had progressive disease. The median duration of response was 12 months; median time to progression, 7.2 months; median survival, 25.7 months. Common grade 3/4 toxicities were neutropenia in 17 (42.5%) patients each, grade 3 leukopenia in 19 (47.5%), and grade 3 alopecia in 30 (75.0%) patients; 1 (2.5%) patient had grade 4 thrombocytopenia.

Conclusion

GT exhibited encouraging activity and tolerable toxicity as first-line therapy in metastatic breast cancer. Phase III trials for further evaluation are ongoing.

Weekly Paclitaxel Improves Pathologic Complete Remission in Operable Breast Cancer When Compared With Paclitaxel Once Every 3 Weeks

Purpose

To determine the impact a change in schedule of paclitaxel administration from once every 3 weeks to frequent administration would have on the pathologic complete response (pCR) rate in the breast and lymph nodes for patients with invasive breast cancer treated with primary systemic chemotherapy (PST).

Patients and Methods

Patients with clinical stage I-IIIA breast cancer were randomly assigned to receive PST of paclitaxel doses administered either weekly (for a total of 12 doses of paclitaxel) or once every 3 weeks (four cycles), followed by four cycles of fluorouracil/doxorubicin/cyclophosphamide (FAC) in standard doses every 3 weeks. Two different doses of paclitaxel were used based on lymph node status defined by ultrasound and fine needle aspiration. Clinical response and extent of residual disease in the breast and lymph nodes was assessed after completion of all chemotherapy.

Results

A total of 258 patients were randomly assigned to receive doses of paclitaxel administered either weekly or once every 3 weeks, followed by FAC. Of these 258 patients, 110 patients had histologic lymph node involvement and 148 patients had clinical N0 disease. Weekly paclitaxel followed by FAC was administered to 127 patients and once-every-3-weeks paclitaxel followed by FAC was administered to 131 patients. Clinical response to treatment was similar between groups (P = .25). Patients receiving weekly paclitaxel had a higher pCR rate (28.2%) than patients treated with once-every-3-weeks paclitaxel (15.7%; P = .02), with improved breast conservation rates (P = .05).

Conclusion

The change in schedule of paclitaxel from once every 3 weeks to a more frequent administration significantly improved the ability to eradicate invasive cancer in the breast and lymph nodes.

Paclitaxel after doxorubicin plus cyclophosphamide as adjuvant chemotherapy for node-positive breast cancer: results from NSABP B-28

PURPOSE

The primary aim of National Surgical Adjuvant Breast and Bowel Project (NSABP) B-28 was to determine whether four cycles of adjuvant paclitaxel (PTX) after four cycles of adjuvant doxorubicin/cyclophosphamide (AC) will prolong disease-free survival (DFS) and overall survival (OS) compared with four cycles of AC alone in patients with resected operable breast cancer and histologically positive axillary nodes.

PATIENTS AND METHODS

Between August 1995 and May 1998, 3,060 patients were randomly assigned (AC, 1,529; AC followed by PTX [AC --> PTX], 1,531). Patients > or = 50 years and those younger than 50 years with estrogen receptor (ER) or progesterone receptor (PR) -positive tumors also received tamoxifen for 5 years, starting with the first dose of AC. Postlumpectomy radiotherapy was mandated. Postmastectomy or regional radiotherapy was prohibited. Median follow-up is 64.6 months.

RESULTS

The addition of PTX to AC significantly reduced the hazard for DFS event by 17% (relative risk [RR], 0.83; 95% CI, 0.72 to 0.95; P = .006). Five-year DFS was 76% +/- 2% for patients randomly assigned to AC --> PTX compared with 72% +/- 2% for those randomly assigned to AC. Improvement in OS was small and not statistically significant (RR, 0.93; 95% CI, 0.78 to 1.12; P = .46). Five-year OS was 85% +/- 2% for both groups. Subset analysis of the effect of paclitaxel according to hormone receptors or tamoxifen administration did not reveal statistically significant interaction (for DFS, P = .30 and P = .44, respectively). Toxicity with the AC --> PTX regimen was acceptable for the adjuvant setting.

CONCLUSION

The addition of PTX to AC resulted in significant improvement in DFS but no significant improvement in OS with acceptable toxicity. No significant interaction between treatment effect and receptor status or tamoxifen administration was observed.