Prospective randomized trial of docetaxel versus doxorubicin in patients with metastatic breast cancer

Second and subsequent lines of chemotherapy for metastatic breast cancer: what did we learn in the last two decades?

Despite almost 30 years of clinical cancer research, the true impact of second and subsequent lines of chemotherapy on the outcome of metastatic breast cancer patients, especially on the duration of survival, is still unknown. In the virtually incurable metastatic setting, issues like quality of life and patients' preferences gain particular relevance. At the turn of the century, in-depth rethinking of the design of clinical trials run in this challenging disease setting appears to be warranted.

Liposome-encapsulated doxorubicin compared with conventional doxorubicin in a randomized multicenter trial as first-line therapy of metastatic breast carcinoma

BACKGROUND

The objective of this study was to compare the efficacy and toxicity of the liposome-encapsulated doxorubicin, TLC D-99 (Myocet, Elan Pharmaceuticals, Princeton, NJ), and conventional doxorubicin in first-line treatment of metastatic breast carcinoma (MBC).

METHODS

Two hundred twenty-four patients with MBC and no prior therapy for metastatic disease were randomized to receive either TLC D-99 (75 mg/m(2)) or doxorubicin (75 mg/m(2)) every 3 weeks, in the absence of disease progression or unacceptable toxicity. The primary efficacy endpoint was response rate. Responses were assessed using World Health Organization criteria and were required to be of at least 6 weeks' duration. The primary safety endpoint was cardiotoxicity. Cardiac function was monitored by multiple-gated radionuclide cardioangiography scan, and the left ventricular ejection fraction (LVEF) was scored at a central laboratory. Patients were removed from study if LVEF declined 20 or more EF units from baseline to a final value of greater than or equal to 50%, or by 10 or more units to a final value of less than 50%, or onset of clinical congestive heart failure (CHF).

RESULTS

Median age was 54 years in both treatment groups. All relevant prognostic factors were balanced, with the exception that there were significantly more progesterone receptor positive patients in the doxorubicin-treated group. Protocol-defined cardiotoxicity was observed in 13% of TLC D-99 patients (including 2 cases of CHF) compared to 29% of doxorubicin patients (including 9 cases of CHF). Median cumulative doxorubicin dose at onset of cardiotoxicity was 785 mg/m(2) for TLC D-99 versus 570 mg/m(2) for doxorubicin (P = 0.0001; hazard ratio, 3.56). The overall response rate was 26% in both treatment groups. The median TTP was 2.9 months on TLC D-99 versus 3.1 months on doxorubicin. Median survival was 16 versus 20 months with a nonsignificant trend in favor of doxorubicin (P = 0.09). Clinical toxicities, commonly associated with doxorubicin, appeared less common with TLC D-99, although the difference was not statistically significant. There was only one report of palmar-plantar erythrodysesthesia (Grade 2) with this liposomal formulation of doxorubicin.

CONCLUSIONS

Single-agent TLC D-99 produces less cardiotoxicity than doxorubicin, while providing comparable antitumor activity.

The choice of adjuvant combination therapies with taxanes: rationale and issues addressed in ongoing studies

The taxanes are emerging as the most powerful compounds in breast cancer. Both compounds, paclitaxel and docetaxel, have been evaluated in the metastatic setting before proceeding with adjuvant trials. Docetaxel was shown in phase III trials to be superior, in particular, in terms of time to progression and survival, to salvage polychemotherapies after failure of prior chemotherapy including anthracyclines. Also, after failure of alkylating agents, a benefit in favor of docetaxel was reported when compared to doxorubicin, whereas paclitaxel was reported to be either as efficacious or inferior to doxorubicin, while being comparable to cyclophosphamide/methotrexate/5-fluorouracil. The role of taxanes in combination with anthracyclines in first-line therapy of advanced breast cancer is still unclear although emerging. One phase III trial showed the significant superiority of doxorubicin/docetaxel (AT) versus doxorubicin/cyclophosphamide (AC) in terms of response and time to progression. Several phase II studies with paclitaxel (over 3 hours) and anthracyclines in the metastatic setting showed high efficacy, but they also showed cardiac toxicity related to a pharmacokinetic interaction between the 2 agents. This fact led to the implementation of metastatic strategies (several phase III trials) aimed at avoiding the pharmacokinetic interaction or specifically limiting the cardiac toxicity that resulted in contradictory results. Consequently, adjuvant strategies with paclitaxel focused mostly on the sequential approach (AC followed by paclitaxel). In contrast, adjuvant strategies with docetaxel/anthracycline-based programs were implemented following both sequential and combination approaches. Results of all of these trials in the adjuvant setting are eagerly awaited in order to establish the role of taxanes in adjuvant breast cancer.

Weekly docetaxel (Taxotere) in patients with metastatic breast cancer

BACKGROUND

Docetaxel (Taxotere) has demonstrated high antitumour activity in first- and second-line treatment of metastatic breast cancer. This study analysed the efficacy and toxicity of docetaxel given weekly.

PATIENTS AND METHODS

Thirty-five patients with metastatic breast cancer received docetaxel, 35 mg/m2 weekly for six weeks, followed by two weeks without treatment. Additional cycles (three weeks' treatment, two weeks' rest) were given until disease progression. All patients had received prior chemotherapy: 32 and 5 patients had received prior anthracycline-containing and taxane-containing regimens, respectively. Docetaxel was administered for a total of 359 doses (median 9. range 6-22).

RESULTS

There was one complete response (3%), 11 partial responses (31%), 17 patients with stable disease (49%) and six with disease progression (17%). Overall response rate was 34% (95% confidential interval (95% CI): 18%-51). Median survival was 307 days; median progression-free survival was 2.6 months (range 1.5 to > or = 5.5 months). Three patients showed grade 3 neutropenia. 14 showed grade 3 alopecia, and various grade 1-2 non-haematological toxicities were observed. Treatment was delayed in two patients due to haematotoxicity. and stopped in one patient due to painful nail toxicity.

CONCLUSION

Weekly administration of docetaxel at a dose of 35 mg/m2 is effective and of low toxicity in patients with metastatic breast cancer.

Combining the anti-HER2 antibody trastuzumab with taxanes in breast cancer: results and trial considerations

Overexpression of the p185/HER2 protein is seen in 20%-25% of primary breast cancers and is associated with poor prognosis. Recent phase II and III clinical trials demonstrate that trastuzumab is active against breast tumors, both as a single agent and in combination with chemotherapy. In patients with HER2-overexpressing metastatic breast cancer, use of trastuzumab in combination with chemotherapy is associated with a 20% reduction in relative risk of death and an increase in median survival from 20.3 to 25.1 months compared to chemotherapy alone. Side effects include fever and chills and an unexpected increase in doxorubicin/trastuzumab-associated cardiomyopathy. Clinical development is now focused on trastuzumab in combination with chemotherapy regimens that do not contain an anthracycline. Trastuzumab in combination with docetaxel is synergistic in vitro. Data from ongoing clinical trials are consistent with this finding. Preliminary data from 3 phase II studies suggest a 44%-63% response rate when the combination is used first or second line in HER2-overexpressing metastatic breast cancer. The combination of docetaxel with trastuzumab is well tolerated and has not been associated with significant cardiotoxicity. Given in vitro evidence that platinum salts act synergistically with trastuzumab and docetaxel, and phase II data suggesting clinical efficacy and good tolerability, the combination of platinum salt plus trastuzumab and docetaxel is now being assessed in adjuvant trials

First-line chemotherapy with docetaxel for unresectable or metastatic carcinoma of the biliary tract. A multicentre phase II study

The purpose was to evaluate the efficacy and safety profile of docetaxel as first-line chemotherapy for patients with locally advanced or metastatic biliary tract carcinoma. 25 chemotherapy-naïve patients with unresectable or metastatic biliary tract carcinoma were entered into this phase II trial. Docetaxel was given at the dose of 100 mg/m2 as a 1-h infusion on day 1, after appropriate premedication with dexamethasone; treatment was repeated every 21 days. Patients were assessed for response every three chemotherapy cycles. 24 patients were evaluable for response and 25 for toxicity. A total of 98 cycles were administered with a median of three cycles/patient. Two complete (CR=8%) and three partial (PR=12%) responses were observed (overall response rate: 20%; 95% confidence interval (C.I.) 4-36%); in addition, 6 (24%) patients had stable disease and 14 (58%) progressive disease. With a median follow-up of 8 months, the median duration of response was 4 months, the median time to tumour progression (TTP) was 6 months and the overall median survival was 8 months. The 1-year survival rate was 26%. Grade 3 and 4 granulocytopenia occurred in 36 and 20% of the patients, respectively, and febrile neutropenia was observed in 16% of them; there were no treatment-related deaths. Grade 2-3 fatigue was reported in 24% of patients. These results indicate that docetaxel is an active drug against adenocarcinomas of the biliary tract.

Monthly docetaxel and weekly gemcitabine in metastatic breast cancer: a phase II trial

BACKGROUND

Docetaxel and gemcitabine are active against breast cancer. The purpose of this phase II study was to evaluate the efficacy and safety of monthly docetaxel combined with weekly gemcitabine in patients with chemotherapy-pretreated metastatic breast cancer.

PATIENTS AND METHODS

Thirty-nine patients were enrolled, of whom thirty had received prior chemotherapy in the adjuvant setting, seven for metastatic disease, and two for both, including prior anthracycline in 33 patients. Treatment was gemcitabine 800 mg/m2 days 1, 8, 15 and docetaxel 100 mg/M2 on day 1, with cycles repeated every four weeks.

RESULTS

Response rate was 79% (95% confidence interval (CI): 63%-91%), with 2 complete and 29 partial responses. Twenty-five of the responders remained progression-free for more than six months. Median survival was 24.5 months. Delivered dose intensity of gemcitabine was lower than expected (63% of planned). The predominant hematologic toxicity was grade 4 neutropenia in 36 patients, complicated by fever in three patients. With the exception of asthenia, severe non-hematological toxicities were infrequent.

CONCLUSIONS

Monthly docetaxel, combined with weekly gemcitabine, has significant but manageable hematologic toxicity. Despite frequent dose adjustments, this doublet is very active in metastatic breast cancer, producing a high proportion of durable responses associated with favorable survival.

Identification of the highest dose of docetaxel associable with active doses of epirubicin. Results from a dose-finding study in advanced breast cancer patients

PURPOSE

To determine the maximum tolerated dose (MTD) and the dose limiting toxicity (DLT) of docetaxel in combination with fixed doses of epirubicin.

PATIENTS AND METHODS

Women with locally advanced or metastatic breast cancer were given docetaxel, 60 mg/m2 in escalated doses by steps of 10 mg/m2, in association with two fixed doses of epirubicin (90 mg/m2, and 75 mg/m2). Since neutropenia was foreseen to be the most likely DLT, a third group with prophylactic G-CSF support was planned to define the MTD of docetaxel with 90 mg/m2 of epirubicin. Selected patients underwent pharmacokinetic evaluation of docetaxel.

RESULTS

Fifty-eight patients entered the study. At the first step (90 mg/m2 of epirubicin) the MTD was obtained at 60 mg/m2 of docetaxel. At the second step (75 mg/m2 of epirubicin) the MTD of docetaxel was 80 mg/m2. At the third step (epirubicin 90 mg/m2) G-CSF allowed a safe escalation of docetaxel up to 90 mg/m2. Neutropenia was the most common hematological adverse event. Without G-CSF, grade 4 neutropenia occurred in 69% of cycles, of which 11% was complicated by fever. In G-CSF group, grade 4 neutropenia and neutropenic fever occurred in 31% and 3%, respectively. Most frequent non-hematological adverse effects were asthenia (45%), nausea (39%) and mucositis (36%). No patient developed congestive heart failure. Two toxic deaths occurred. Overall response rate was 73% in 42 out of 58 patients, with no apparent epirubicin dose-related effect. No statistically significant effect of the two doses of epirubicin was observed in docetaxel pharmacokinetics.

CONCLUSIONS

On the basis of the toxicity profile, the docetaxel pharmacokinetics and the response rate observed, epirubicin 75 mg/m2 combined with docetaxel 80 mg/m2 can be recommended for further studies.

Docetaxel: overview of an active drug for breast cancer

Docetaxel and paclitaxel differ in their precise molecular targets and pharmacokinetics. Docetaxel is more avidly taken up by tumor cell lines than paclitaxel, and its efflux is slower. Comparative cytotoxicity data suggest greater potency. These factors may help explain the clinical differences that have been observed between the taxanes in patients with breast cancer.

Nonanthracycline containing docetaxel-based combinations in metastatic breast cancer

Many active nonanthracycline-containing regimens are emerging from clinical trials and may offer the option of treating metastatic breast cancer without resorting to doxorubicin or analogues. When used first-line in metastatic breast cancer, both cisplatin and carboplatin are active agents and hence candidates for combination therapy. In a dose-finding study in patients with no prior chemotherapy for metastatic disease, docetaxel administered together with cisplatin produced a promising response rate (RR) of 60% (73% in patients without prior adjuvant chemotherapy). The combination is feasible, although adequate hydration and antiemetic medication must be given. There is also an early indication that it may be possible to dramatically cytoreduce disease in patients with locally advanced breast cancer who are treated with docetaxel plus cisplatin. Given its lower toxicity, carboplatin may also have a role in combination with the taxanes. Of the nonplatinum agents, vinorelbine appears to hold promise; its combination with docetaxel produced an RR of 59% in a group of anthracycline-pretreated patients with progressive disease. Forty-two percent of the patients studied also had prior exposure to a taxane. Weekly gemcitabine plus monthly docetaxel is feasible and active, as is the combination of docetaxel q 3 weeks with daily oral capecitabine.

Docetaxel and herceptin: foundation for future strategies

Randomized controlled studies have demonstrated that both docetaxel and Herceptin are capable of increasing survival in patients with metastatic breast cancer. The two agents show synergy in vitro, and their use in combination is not likely to be associated with the problem of enhanced cardiotoxicity. In two trials of Herceptin plus docetaxel in patients with advanced breast cancer, preliminary data are available for 35 patients. These early results show that the combination is well-tolerated. No symptomatic cardiotoxicity has occurred. The preliminary response rates (RR) in these first- and second-line patients are 44% in one study and 63% in the other. In the subgroups of patients who were HER-2 3+ overexpressers, the RRs are currently 55% and 73%. In an attempt to maximize the efficacy of Herceptin, its use has also been studied in combination with docetaxel and a platinum salt, producing a preliminary RR of 78% in patients positive for HER-2 on the fluorescence in situ hybridization assay. These data are sufficiently promising to justify a study of the role of Herceptin in combination with adjuvant chemotherapy regimens containing docetaxel or docetaxel plus a platinum. The combination of Herceptin with adjuvant therapy containing docetaxel and a platinum may provide a helpful alternative to the potentially cardiotoxic Herceptin/anthracycline-containing regimens currently under investigation.

Taxane/anthracycline combinations: setting a new standard in breast cancer?

Among the novel chemotherapeutic drugs introduced in the 1990s, the taxanes have emerged as the most powerful compounds in breast cancer. Both compounds, paclitaxel and docetaxel, have been evaluated in metastatic settings before adjuvant trials proceeded. Docetaxel was shown in several phase III trials to be superior, particularly in terms of survival, for salvaging polychemotherapies after failure of prior chemotherapy, including that with anthracyclines. A benefit of docetaxel was also reported when compared with doxorubicin after failure of alkylating agents. In phase III trials paclitaxel was reported to be as efficacious over 24 hours as doxorubicin 60 mg/m(2), while paclitaxel was significantly inferior to doxorubicin 75 mg/m(2) over 3 hours and was close to CMF in another trial. The role of taxanes in combination with anthracyclines in first-line therapy of advanced breast cancer is emerging. Following several phase II studies, a phase III trial showed the significant superiority of docetaxel/doxorubicin (AT) versus doxorubicin/cyclophosphamide (AC) in terms of response and time to progression. In several phase II studies with paclitaxel (3 hours), anthracyclines in the metastatic setting showed high efficacy but produced cardiac toxicity related to a pharmacokinetic interaction between the two agents. This finding led to the implementation of metastatic strategies (phase III trials) aimed at avoiding the pharmacokinetic interaction, while the adjuvant strategies with paclitaxel focused primarily on the sequential approach (AC followed by paclitaxel). In contrast, adjuvant strategies with docetaxel/anthracycline-based programs were implemented following both sequential and combination approaches.

Docetaxel and epirubicin in advanced breast cancer

In an International Breast Cancer Study Group phase I/II program, 70 patients with advanced breast cancer received up to eight courses of 75 mg/m2 docetaxel combined with 90 mg/m(2) epirubicin, every 3 weeks. G-CSF was not administered prophylactically. Grade 4 neutropenia occurred in 88% of cycles that were not supported by G-CSF. However, febrile neutropenia affected only 24% of cycles. It occurred after the first cycle in 56% of cases and was managed by oral antibiotics in 52% of cases. When supportive G-CSF was administered, the incidence of febrile neutropenia fell to 3% and grade 4 neutropenia to 41%. Only 6% of patients experienced a greater than 20% reduction in left ventricular ejection fraction and no severe, irreversible cardiotoxicity was observed. The overall response rate (RR) was 66% and median time to progression was 4.5 months. The RR was similar in patients with prior adjuvant chemotherapy and patients with predominantly visceral disease. These data and those of comparable series suggest that the combination of epirubicin and docetaxel is tolerable and active, and that it should be further developed clinically.

Chemotherapy of metastatic breast cancer: what to expect in 2001 and beyond

Chemotherapy plays an important role in the management of metastatic breast cancer. The anthracyclines (doxorubicin, epirubicin) and the taxanes (paclitaxel, docetaxel) are considered the most active agents for patients with advanced breast cancer. Traditionally, the anthracyclines have been used in combination with cyclophosphamide and 5-fluorouracil (FAC, FEC). The taxanes have single-agent activity similar to older combination chemotherapy treatments. There is great interest in developing anthracycline/taxane combinations. Capecitabine is indicated for patients who progress after anthracycline and taxane therapy. Vinorelbine and gemcitabine have activity in patients with metastatic breast cancer and are commonly used as third- and fourth-line palliative therapy. The role of high-dose chemotherapy is not well-defined and remains experimental. Novel cytotoxic therapy strategies include the development of anthracycline, taxane, and oral fluoropyrimidine analogues; antifolates; topoisomerase I inhibitors, and multidrug resistance inhibitors. A better understanding of the biology of breast cancer is providing novel treatment approaches. Oncogenes and tumor-supressor genes are emerging as important targets for therapy. Trastuzumab, a monoclonal antibody directed against the Her-2/neu protein, has been shown to prolong survival in patients with metastatic breast cancer. Other novel biologic therapies interfere with signal transduction pathways and angiogenesis. The challenge for the next decade will be to integrate these promising agents in the management of metastatic and primary breast cancer.

Phase I dose-finding and pharmacokinetic study of docetaxel and vinorelbine as first-line chemotherapy for metastatic breast cancer

BACKGROUND AND PURPOSE

Anthracycline-containing regimens are widely used in advanced breast cancer. However, there is a need for new, non-anthracycline regimens that are active in patients for whom anthracyclines are contraindicated. The aim of this study was to determine the maximum tolerated dose (MTD), the dose-limiting toxicities (DLTs) and recommended doses of docetaxel and vinorelbine as first-line chemotherapy in patients with metastatic breast cancer. The pharmacokinetics of both drugs was also evaluated.

PATIENTS AND METHODS

Thirty-four women with first-line metastatic breast cancer were treated with docetaxel, 60-100 mg/m2 (day 1), and vinorelbine, 20-22.5 mg/m2 (days 1 and 5), repeated every three weeks and administered on an outpatient basis.

RESULTS

Two MTDs were determined: MTD1 was defined at the dose level using docetaxel 75 mg/m2, and vinorelbine 22.5 mg/m2 DLT being a grade 3 stomatitis that was more related to the dose of vinorelbine than that of docetaxel. Therefore, the study continued with a fixed dose of vinorelbine, 20 mg/m2, and docetaxel 85-100 mg/m2. MTD2 was defined at the dose level combining docetaxel, 100 mg/m2, and vinorelbine, 20 mg/m2; DLTs were grade 3 stomatitis and severe asthenia. Fluid retention was observed in 41% of patients but was never severe or a reason for patient discontinuation. In comparison with historical experience, Daflon 500 did not seem to increase the efficacy of the three-day corticosteroid premedication by further reducing the incidence or severity of fluid retention. No significant neurotoxicity was observed and no patient discontinued the study due to this site effect. Activity was observed at all dose levels and at all metastatic sites, with an overall response rate of 71% (95% CI: 52.0%-85.8%). The median time to progression was 31.4 weeks (95% CI: 12-48 weeks) and median survival was 15.6 months (95% CI: 2.6-26.6 months). The pharmacokinetics of docetaxel and vinorelbine were not modified between day 1 and day 3 when the two drugs were combined with the day 1 administration schedule used in this study.

CONCLUSION

The recommended doses for phase II studies are docetaxel, 75 mg/m2 (day 1), plus vinorelbine, 20 mg/m2 (days 1 and 5), repeated every three weeks. At these doses, the combination was found to be active and well tolerated.

Docetaxel in combination with mitoxantrone and granulocyte colony-stimulating factor as front-line chemotherapy in metastatic breast cancer: a multicenter phase II study

PURPOSE

To evaluate the activity and tolerance of docetaxel in combination with mitoxantrone and granulocyte colony-stimulating factor (G-CSF) as front-line treatment in patients with metastatic breast cancer (MBC).

PATIENTS AND METHODS

Fifty-four previously untreated patients with MBC who had bidimensionally measurable disease were enrolled onto the study. Forty-eight (89%) patients had visceral metastases and nineteen (36%) had relapsed within twelve months following adjuvant chemotherapy. Docetaxel (100 mg/m2) was given on day 1 after appropriate premedication and mitoxantrone (20 mg/m2) on day 8. G-CSF (150 mcg/m2/d s.c.) was administered from day 2 to day 6 and from day 9 to day 15. The regimen was repeated every three weeks, on an outpatient basis.

RESULTS

In an intention-to-treat analysis, 9 (17%) CRs, 24 (44%) PRs, (overall response rate 61%; 95% confidence interval (CI): 48.1%-74.1%), 12 (22%) SD and 9 (17%) PD were observed. The median duration of response and the median time to tumor progression was 12.5 and 14 months, respectively. The overall median survival was 16.5 months, whilst the probability for one- and three-year survival was 61% and 35%, respectively. Grade 3-4 neutropenia occurred in 37 (69%) patients, and febrile neutropenia in 16 (30%); there was one death due to sepsis. Grade 3-4 thrombocytopenia occurred in four (8%) patients. Grade 2-3 neurosensory toxicity was observed in 8 (15%) patients and grade 2-3 asthenia in 24 (45%).

CONCLUSIONS

Docetaxel in combination with mitoxantrone and G-CSF support is an intensified and active front-line regimen for patients with MBC; despite its hematological toxicity, this regimen merits further comparison with other standard anthracycline- and/or taxane-based combinations.

Oral fluoropyrimidines among the new drugs for patients with metastatic breast cancer

Although drugs such as the taxoids and vinorelbine have increased the options available for anthracycline-resistant metastatic breast cancer, new therapeutic options are needed, particularly for taxoid-refractory tumours. Increasing emphasis is being placed on the development of oral agents, which many patients prefer provided efficacy is not compromised, particularly if the oral agents are less toxic than current intravenous agents. Capecitabine, a new, oral fluoropyrimidine, mimics continuous infusion 5-FU and is activated preferentially at the tumour site. Phase II studies of capecitabine have demonstrated encouraging response rates in patients with few further treatment options (20% response with an additional 43% achieving stable disease in paclitaxel-refractory patients; 36% response with a further 23% achieving stable disease in anthracycline-refractory patients). In addition, a randomized, phase II trial demonstrated a response rate of 30% (95% Cl: 19-43%) with capecitabine as first-line treatment for metastatic breast cancer, compared with 16% (95% Cl: 5-33%) in patients receiving low-dose CMF. These trials also showed that capecitabine has a favourable safety profile typical of infused fluoropyrimidines. Both alopecia and myelosuppression were rare. Capecitabine may therefore provide an effective, well-tolerated and convenient alternative to intravenous cytotoxic agents, not only in taxoid-resistant patients, but also in anthracycline-resistant metastatic breast cancer or as first-line therapy. Furthermore, the low incidence of myelosuppression makes capecitabine an attractive agent for incorporation into combination regimens with agents such as epirubicin/doxorubicin, the taxoids and vinorelbine.

Systemic treatment of metastatic breast cancer

This article reviews recent advances in the treatment of metastatic breast cancer, in particular the results of randomized controlled phase III clinical trials. These have led to the evidence-based introduction of several new drugs including aromatase inhibitors, taxanes and bisphosphonates, some of which have been shown to impact on overall survival.

Doxorubicin and paclitaxel versus fluorouracil, doxorubicin, and cyclophosphamide as first-line therapy for women with metastatic breast cancer: final results of a randomized phase III multicenter trial

PURPOSE

This phase III trial compared the efficacy and safety of doxorubicin and paclitaxel (AT) to 5-fluorouracil, doxorubicin, and cyclophosphamide (FAC) as first-line therapy for women with metastatic breast cancer.

PATIENTS AND METHODS

A total of 267 women with metastatic breast cancer were randomized to receive either AT (doxorubicin 50 mg/m(2) followed 24 hours later by paclitaxel 220 mg/m(2)) or FAC (5-fluorouracil 500 mg/m(2), doxorubicin 50 mg/m(2), cyclophosphamide 500 mg/m(2)), each administered every 3 weeks for up to eight cycles. Patients had to have measurable disease and an Eastern Cooperative Oncology Group performance status of 0 to 2. Only one prior non-anthracycline, nontaxane-containing adjuvant chemotherapy regimen was allowed.

RESULTS

Overall response rates for patients randomized to AT and FAC were 68% and 55%, respectively (P =.032). Median time to progression and overall survival were significantly longer for AT compared with FAC (time to progression 8.3 months v 6.2 months [P =.034]; overall survival 23.3 months v 18.3 months [P =.013]). Therapy was generally well-tolerated (median of eight cycles delivered in each arm). Grade 3 or 4 neutropenia was more common with AT than with FAC (89% v 65%; P <.001); however, the incidence of fever and infection was low. Grade 3 or 4 arthralgia and myalgia, peripheral neuropathy, and diarrhea were more common with AT, whereas nausea and vomiting were more common with FAC. The incidence of cardiotoxicity was low in both arms.

CONCLUSION

AT conferred a significant advantage in response rate, time to progression, and overall survival compared with FAC. Treatment was well-tolerated with no unexpected toxicities.

Phase II study of docetaxel, doxorubicin, and cyclophosphamide as first-line chemotherapy for metastatic breast cancer

PURPOSE

This pilot phase II study investigated the efficacy and toxicity of docetaxel with doxorubicin and cyclophosphamide (TAC) as first-line chemotherapy for anthracycline-naive patients with metastatic breast cancer.

PATIENTS AND METHODS

Fifty-four patients received a total of 359 courses consisting of docetaxel 75 mg/m2 given intravenously (IV) over 1 hour, preceded by IV doxorubicin 50 mg/m2 and cyclophosphamide 500 mg/m2 for a maximum of eight 3-week cycles.

RESULTS

After an independent panel review, the overall objective response rate was 77% (complete response, 6%). Overall objective response rates in patients with visceral, bone, and liver involvement were 82%, 82%, and 80%, respectively. Median duration of response was 52 weeks, and median time to progression was 42 weeks. With a median follow-up of 32 months, the median survival had not yet been reached, whereas the 2-year survival was 57%. The main toxicities were hematologic (neutropenia grade 3/4 in 100% of patients and 95% of cycles; febrile neutropenia in 34% of patients and 9% of cycles). Documented grade 3 infection was seen in one patient (2%) in one cycle, and no toxic death was reported. Severe acute or chronic nonhematologic adverse events were infrequent, and docetaxel-specific toxicities (such as fluid retention and nail changes) were mild, with only one patient being discontinued for fluid retention. Congestive heart failure was seen in two patients (4%).

CONCLUSION

TAC is an active and manageable regimen that has been chosen as the basis of five randomized phase III trials, including two pivotal studies comparing TAC to fluorouracil plus doxorubicin and cyclophosphamide in the metastatic and adjuvant treatment of breast cancer.

New horizons in treating metastatic disease

The management of metastatic breast cancer is changing as a consequence of extraordinary discoveries in cancer research and the development of more advanced diagnostic technologies. Although traditional chemotherapeutics such as anthracyclines and taxanes still represent the mainstay of treatment for this disease, new drugs are demonstrating significant clinical activity and sometimes a better toxicity profile. Furthermore, the successful introduction into clinical practice of biological agents, in particular the monoclonal antibody trastuzumab, offers a key to the future of managing metastatic breast cancer. A therapeutic approach based on modifications of a specific molecular target (e.g., gene therapy, vaccines, and antiangiogenesis) alone or combined with the traditional chemotherapeutic drugs is expected to be used more commonly and will, we hope, bring significant improvement in the clinical response and quality of care of our patients.

Cost effectiveness of treatment options in advanced breast cancer in the UK

OBJECTIVE

To compare clinical and economic study data for docetaxel, paclitaxel and vinorelbine in the treatment of anthracycline-resistant advanced breast cancer.

STUDY DESIGN AND METHODS

A Markov decision-analysis model to simulate the clinical course of a 'typical' patient with advanced breast cancer during salvage chemotherapy was updated with response rates and adverse effect rates from phase III clinical trial data for docetaxel, paclitaxel and vinorelbine. Costs were taken from UK national databases and hospitals. Utilities were estimated from 30 oncology nurses in the UK using the standard gamble method.

PERSPECTIVE

National Health Service.

RESULTS

When compared with other chemotherapeutic agents, docetaxel has been shown to increase response rate, time to progression and survival in patients with advanced breast cancer. In the base-case analysis, the incremental cost-utility ratio for docetaxel versus paclitaxel was pound1995 per quality-adjusted life year (QALY) gained (1998 values). The incremental cost-utility ratio for docetaxel versus vinorelbine was pound14 055 per QALY gained. In the comparison with vinorelbine, docetaxel provided the equivalent of an additional 92 days of perfect health. Sensitivity analyses confirmed the robustness of the model and the validity of the base-case analysis results. Even in the worst case scenarios, docetaxel remained cost effective compared with paclitaxel and vinorelbine.

CONCLUSIONS

These findings support the use of the taxoids, notably docetaxel, in the management of advanced breast cancer.

Risks and benefits of taxanes in breast and ovarian cancer

The taxanes are a unique class of agents with a broad spectrum of clinical activity. They act by binding to tubulin, producing unnaturally stable microtubules and subsequent cell death. The distribution and elimination of paclitaxel depend on dose and administration rate. This nonlinearity is much less evident at lower infusion rates (24-hour infusions) and more evident at high plasma concentrations (3-hour infusions). The pharmacokinetics of docetaxel also suggest the presence of nonlinear pathways, but these appear to be clinically insignificant at the current doses utilised (60 to 100 mg/m2). Both agents undergo hepatic metabolism and biliary excretion and require dose adjustment in the setting of liver dysfunction. Drug interactions are quite common with these agents, some of which are sequence-dependent and clinically significant. The optimal dose of paclitaxel is not known at this time, and controversy over possible dose- or schedule-related differences in efficacy still remain. Docetaxel is somewhat more consistent in its dose and scheduling information, but controversy remains regarding a dose-benefit relationship as well as scheduling differences (weekly vs every 3 weeks). Toxicity profiles for these agents are somewhat different. Paclitaxel is more likely to be associated with peripheral neuropathy and myalgias/arthralgias than docetaxel. Docetaxel is more likely to be associated with a cumulative fluid retention syndrome that can be dose limiting. Paclitaxel and docetaxel are both highly active agents against breast cancer, including tumours that are resistant to anthracyclines. Docetaxel tends to have higher response rates overall, but direct comparisons at maximally tolerated doses have not been completed. Combination regimens with many different agents are attempting to improve on the responses seen with single-agent taxanes. The combination of paclitaxel and a platinum compound should be utilised as first-line therapy of advanced ovarian cancer. Controversy lies in the choice of the platinum compound and the dose and administration schedule of paclitaxel. Substitution of docetaxel for paclitaxel in these platinum-containing regimens is also being investigated. The taxanes also exhibit activity against ovarian cancer in patients previously exposed to platinum agents. These agents may also be administered intraperitoneally for local therapy of metastatic ovarian cancer. Although docetaxel and paclitaxel are often considered similar in activity and tolerability, this review emphasises the fact that these agents are indeed different. Clinicians need to be familiar with the benefits and adverse events related to each agent in order to make informed, appropriate clinical decisions.

Systemic therapy

Our knowledge base on systemic therapy for breast cancer continues to expand, including further information regarding hormonal prevention in high-risk women, beneficial effects of tamoxifen in noninvasive disease, an update on primary systemic therapy, and optimization of adjuvant strategies, including data on adjuvant chemoendocrine regimens. The proper evaluation of high-dose strategies has been jeopardized by a serious episode of scientific misconduct. New data are also available on palliative options, bisphosphonates, antibody therapies, and novel targets. Data continue to evolve on the role and optimal schedules of taxanes in early-stage and advanced breast cancer. These and other important recent findings are discussed in this review article.

Front-line treatment of advanced breast cancer with docetaxel and epirubicin: a multicenter phase II study

PURPOSE

In a previous phase I trial we evaluated the toxicity and determined the maximum tolerated doses of the docetaxel (D)-epirubicin (Epi) combination. We conducted a multicenter phase II study to evaluate the efficacy and tolerability of this regimen as front-line treatment in women with advanced breast cancer (ABC).

PATIENTS AND METHODS

Fifty-four women with ABC stage IIIB (4 patients) or IV (50 patients) received front-line treatment with Epi 70 mg/m2 on day 1 and D 90 mg/m2 on day 2. The median age was 55 years, performance status (WHO) was 0-1 in 49 patients and visceral disease was present in 45 (83%).

RESULTS

All patients were evaluable for toxicity and 50 for response. In an intent-to-treat analysis complete remission was observed in 5(9%) patients, partial remission in 31 (57%) (overall response rate 66%, 95% confidence interval: 54% 79%), stable disease in 9 (17%) and disease progression in 9 (17%). After a median follow-up of 11.5 months, the median duration of responses was 8 months, the median time to disease progression 11.5 months and the median survival has not yet been reached. The probability of one-year survival was 65%. Three hundred six cycles of treatment were administered (median 6 cycles per patient). Grade 3 and 4 neutropenia was observed in 8 (15%) and 31 (57%) patients, respectively, and febrile neutropenia in 19 (35%). Prophylactic rh-G-CSF was used in 45 (83%) patients or 226 (74%) cycles. Other hematologic or non-hematologic toxicities were usually mild. In five (9%) patients the left ventricular ejection fraction (LVEF) was decreased by more than 10% with the treatment. Two patients died during the treatment of respiratory failure without associated neutropenia.

CONCLUSIONS

The combination of docetaxel epirubicin is an effective and well tolerated front-line treatment in patients with ABC.

Gemcitabine and cisplatin versus methotrexate, vinblastine, doxorubicin, and cisplatin in advanced or metastatic bladder cancer: results of a large, randomized, multinational, multicenter, phase III study

PURPOSE

Gemcitabine plus cisplatin (GC) and methotrexate, vinblastine, doxorubicin, and cisplatin (MVAC) were compared in patients with locally advanced or metastatic transitional-cell carcinoma (TCC) of the urothelium.

PATIENTS AND METHODS

Patients with stage IV TCC and no prior systemic chemotherapy were randomized to GC (gemcitabine 1,000 mg/m2 days 1, 8 and 15; cisplatin 70 mg/m2 day 2) or standard MVAC every 28 days for a maximum of six cycles.

RESULTS

Four hundred five patients were randomized (GC, n = 203; MVAC, n = 202). The groups were well-balanced with respect to prognostic factors. Overall survival was similar on both arms (hazards ratio [HR], 1.04; 95% confidence interval [CI], 0.82 to 1.32; P = .75), as were time to progressive disease (HR, 1.05; 95% CI, 0.85 to 1.30), time to treatment failure (HR, 0.89; 95% CI 0.72 to 1.10), and response rate (GC, 49%; MVAC, 46%). More GC patients completed six cycles of therapy, with fewer dose adjustments. The toxic death rate was 1% on the GC arm and 3% on the MVAC arm. More GC than MVAC patients had grade 3/4 anemia (27% v 18%, respectively), and thrombocytopenia (57% v 21%, respectively). On both arms, the RBC transfusion rate was 13 of 100 cycles and grade 3/4 hemorrhage or hematuria was 2%; the platelet transfusion rate was four patients per 100 cycles and two patients per 100 cycles on GC and MVAC, respectively. More MVAC patients, compared with GC patients, had grade 3/4 neutropenia (82% v 71%, respectively), neutropenic fever (14% v 2%, respectively), neutropenic sepsis (12% v 1%, respectively), and grade 3/4 mucositis (22% v 1%, respectively) and alopecia (55% v 11%, respectively). Quality of life was maintained during treatment on both arms; however, more patients on GC fared better regarding weight, performance status, and fatigue.

CONCLUSION

GC provides a similar survival advantage to MVAC with a better safety profile and tolerability. This better-risk benefit ratio should change the standard of care for patients with locally advanced and metastatic TCC from MVAC to GC.

Issues in the treatment of metastatic breast cancer

OBJECTIVES

To provide a discussion of the treatment of metastatic breast cancer, nursing interventions, and quality of life issues for women with advanced breast cancer.

DATA SOURCES

Journal articles and internet web sites.

CONCLUSIONS

Advances in the discovery of new chemotherapeutic regimens, monoclonal antibodies, and bisphosphonates have offered more options for the treatment of metastatic breast cancer. Treatment is aimed at improving survival while maintaining quality of life.

IMPLICATIONS FOR NURSING PRACTICE

Nurses can use this information to educate patients about their cancer treatment. It provides nurses with strategies for management of treatment side effects and will enhance their understanding of quality of life issues for women with metastatic breast cancer.

Quality of life in patients with metastatic breast cancer receiving either docetaxel or sequential methotrexate and 5-fluorouracil. A multicentre randomised phase III trial by the Scandinavian breast group

The purpose of this study was to evaluate the effects of two alternative chemotherapy regimes on the quality of life (QoL) of patients with advanced breast cancer. In a multicentre trial, 283 patients were randomised to receive either docetaxel (T) or sequential methotrexate and 5-fluorouracil (MF). QoL was assessed at baseline and before each treatment using the European Organization for Research and Treatment of Cancer (EORTC) Quality of Life Questionnaire (QLQ-C30). Initial compliance in the QoL study was 96% and the overall compliance 82%. QoL data were available for 245 patients (T 130 and 115 MF). Both treatment groups showed some improvement in emotional functioning during treatment, with a significant difference favouring the MF group at treatment cycles 5 and 6. In the T group, the scores on the other functional scales remained stable throughout the first six cycles. There were significant differences favouring the MF group on the social functioning scale at treatment cycle 6 and on the Global QoL scale at treatment cycles 5 and 6. On most symptom and single-item scales there were no statistically significant differences between the groups. However, at baseline, the T patients reported more appetite loss, at treatment cycles 2-4, the MF patients reported more nausea/vomiting, and at treatment cycle 6, the T patients reported more symptoms of fatigue, dyspnoea and insomnia. There were no statistically significant differences between the groups in the mean change scores of the functional and symptom scales. Interindividual variance was, however, larger in the T group. Differences in QoL between the two treatment groups were minor. Hence, given the expectancy of comparable QoL outcomes, the choice of treatment should be made on the basis of the expected clinical effect.

Phase III comparative study of vinorelbine combined with doxorubicin versus doxorubicin alone in disseminated metastatic/recurrent breast cancer: National Cancer Institute of Canada Clinical Trials Group Study MA8

PURPOSE

This phase III study was performed to determine the superiority of doxorubicin (DOX) and vinorelbine (VNB) (arm 1) versus DOX alone (arm 2) in metastatic breast cancer (MBC) for overall survival (OS), time to treatment failure (TTF), toxicity, and quality of life (QOL).

PATIENTS AND METHODS

Three hundred three patients were randomized to DOX 50 mg/m(2) intravenously (IV) on day 1 and VNB 25 mg/m(2) IV on days 1 and 8 (arm 1) or DOX 70 mg/m(2) IV on day 1 (arm 2). Both regimens were given every 3 weeks until a cumulative DOX dose of 450 mg/m(2). After 16 of the first 65 randomized patients experienced febrile neutropenia (FN), the doses were reduced to DOX 40 mg/m(2) on day 1 and VNB 20 mg/m(2) on days 1 and 8 versus DOX 60 mg/m(2) on day 1. Eligible patients were vinca alkaloid and anthracycline naive. Chemotherapy was first-line or second-line for MBC.

RESULTS

Three patients were ineligible. Thus, 300 patients were assessable for toxicity and to determine time to disease progression (TTP), TTF, and OS. Two hundred eighty-nine patients were assessable for response, and 99 responders were assessable for response duration (RD). The response rates, QOL, and median RD, TTP, and TTF were not significantly different between the arms. Median OS was 13.8 months for arm 1 versus 14.4 months for arm 2 (P =.4). Grade 3 or 4 granulocytopenia was equivalent in both arms but more grade 3/4 neurotoxicity, mild venous toxicity, and FN were seen on arm 1.

CONCLUSION

The survival with DOX and VNB is not superior to DOX alone in MBC.

Phase II study of docetaxel in patients with liver metastases from breast cancer. UK study group

BACKGROUND

Previous phase II studies of docetaxel have indicated that hepatic metastases from breast cancer respond well to first-line treatment with docetaxel. The objective of this prospective, open label phase II study therefore was specifically to evaluate the activity and safety of docetaxel in this indication.

PATIENTS AND METHODS

The study recruited 47 women (mean age 50 years, range 33-66 years) with hepatic metastases from breast cancer who fulfilled the eligibility criteria. After premedication with steroids, patients received a one-hour intravenous infusion of docetaxel 100 mg/m2 at three-weekly intervals for up to eight cycles. Response to treatment during medication was assessed after three, six and where appropriate, eight cycles and every three month follow-up thereafter, until disease progression or death.

RESULTS

The best overall response rate (ORR) for evaluable patients was 64.3% (95% CI: 48.0-78.5%). In terms of the primary efficacy parameters, the ORR at the sixth cycle of treatment was 62% (95% CI: 45%-80%) with 17% complete responses. The median duration of response was 139 days (95% CI: 111-216 days) and the median survival duration calculated on an intent-to-treat basis was 335 days (227-568 days, 95% CI). One (2%) toxic death was reported.

CONCLUSIONS

Docetaxel is a highly effective cytotoxic agent in the treatment of patients with liver metastases from breast cancer.

Taxanes for breast cancer: an evidence-based review of randomized phase II and phase III trials

The taxanes paclitaxel and docetaxel have an important role in the treatment of breast cancer, and numerous randomized trials have evaluated their efficacy for this indication. A systematic, evidence-based review was performed, which included all randomized, controlled trials evaluating taxanes for the treatment of early-or advanced-stage breast cancer that were identified in CANCERLIT and MEDLINE searches. The primary objectives of this review were to determine the dose and schedule for each taxane that was associated with the most favorable therapeutic index, and to determine whether (and under what circumstances) the taxanes improved survival. The search revealed 18 randomized phase II (n = 1) or phase III (n = 17) trials. For metastatic breast cancer, the dose and schedule associated with the most favorable therapeutic index for paclitaxel was 175 mg/m2 given as a 3-hour infusion every 3 weeks, and docetaxel was 60-100 mg/m2 given as a 1-hour infusion every 3 weeks. Survival was improved under the following circumstances: (1) when 4 cycles of paclitaxel (175 mg/m2 every 3 weeks) was given following 4 cycles of conventional doxorubicin-cyclophosphamide for axillary node-positive operable breast cancer, (2) when trastuzumab was added to paclitaxel as first-line therapy for metastatic breast cancer that overexpressed HER2/neu, and (3) when docetaxel was given as second-line therapy for anthracycline-resistant disease. Although a survival benefit was found for taxanes as a component of first-line therapy in two of six trials, the interpretation of both positive trials was confounded by a lack of crossover to taxane therapy in those who were initially randomized to receive standard therapy. The taxanes improve survival in patients with early-stage breast cancer and selected patients with metastatic breast cancer. Further research is necessary in order to identify the efficacy of docetaxel relative to paclitaxel, the optimal dose of docetaxel, the role of weekly taxane therapy, the role of trastuzumab plus taxanes in early-stage disease, and whether taxanes are more effective when given concomitantly or sequentially in patients with early-stage disease.

Docetaxel: an update of its use in advanced breast cancer

Docetaxel, a semisynthetic member of the taxoid class of antineoplastic agents, is effective in the treatment of patients with advanced (locally advanced or metastatic) breast cancer. Reported objective response rates for docetaxel 100 mg/m2 ranged from 54 to 69% and 53 to 82% as first-line monotherapy or combination therapy, respectively. Objective response rates of 23 to 65% and 30 to 81% have been reported for docetaxel as second-line monotherapy or combination therapy, respectively. In Japanese studies, second-line docetaxel 60 mg/m2 produced objective response rates of 42 to 55%. At the recommended dose of 100 mg/m2 given as a 1-hour intravenous (i.v.) infusion every 3 weeks, docetaxel had significantly greater efficacy than doxorubicin, mitomycin plus vinblastine and methotrexate plus fluorouracil, and similar efficacy to fluorouracil plus vinorelbine in pretreated patients with advanced breast cancer. In chemotherapy-naive patients, first-line combined therapy with docetaxel and doxorubicin had significantly greater efficacy than doxorubicin plus cyclophosphamide. Promising results have been achieved in phase I/II trials of a weekly regimen of docetaxel (generally 30 to 45 mg/m2). Preliminary data indicate a potential role for docetaxel in the neoadjuvant therapy of early breast cancer. The major dose-limiting adverse event associated with docetaxel is neutropenia. Although other adverse events are common, the tolerability profile of docetaxel is generally acceptable in the majority of patients, particularly in comparison with other antineoplastic regimens.

CONCLUSIONS

Although no single standard regimen has been identified as optimal for the treatment of advanced breast cancer, phase III trials have shown that docetaxel has improved efficacy over doxorubicin alone (considered one of the current gold standards), methotrexate/fluorouracil and mitomycin/vinblastine in second-line therapy. In combination with doxorubicin, docetaxel has demonstrated better efficacy than doxorubicin/cyclophosphamide in first-line therapy. These results provide a basis for therapy choice in advanced breast cancer. Clinical trials comparing docetaxel monotherapy versus paclitaxel monotherapy and versus docetaxel combination therapy are warranted. The role of docetaxel in the adjuvant and neoadjuvant treatment of early breast cancer is being evaluated.

Docetaxel administered on a weekly basis for metastatic breast cancer

PURPOSE

To evaluate the safety and efficacy of weekly docetaxel in women with metastatic breast cancer.

PATIENTS AND METHODS

Twenty-nine women were enrolled onto a study of weekly docetaxel given at 40 mg/m(2)/wk. Each cycle consisted of 6 weeks of therapy followed by a 2-week treatment break, repeated until disease progression or removal from study for toxicity or patient preference. Fifty-two percent of patients had been previously treated with adjuvant chemotherapy; 21% had received prior chemotherapy for metastatic breast cancer, and 31% had previously received anthracyclines. All patients were assessable for toxicity; two patients were not assessable for response but are included in an intent-to-treat analysis.

RESULTS

Patients received a median of 18 infusions, with a median cumulative docetaxel dose of 720 mg/m(2). There were no complete responses. Twelve patients had partial responses (overall response rate, 41%; 95% confidence interval, 24% to 61%), all occurring within the first two cycles. Similar response rates were observed among subgroups of patients previously treated either with any prior chemotherapy or with anthracyclines. An additional 17% of patients had stable disease for at least 6 months. The regimen was generally well tolerated. There was no grade 4 toxicity. Only 28% of patients had any grade 3 toxicity, most commonly neutropenia and fatigue. Acute toxicity, including myelosuppression, was mild. Fatigue, fluid retention, and eye tearing/conjunctivitis became more common with repetitive dosing, although these side effects rarely exceeded grade 2. Dose reductions were made for eight of 29 patients, most often because of fatigue (n = 5).

CONCLUSION

Weekly docetaxel is active in treating patients with metastatic breast cancer, with a side effect profile that differs from every-3-weeks therapy.

A feasibility study evaluating docetaxel-based sequential and combination regimens in the adjuvant therapy of node-positive breast cancer

BACKGROUND AND PURPOSE

Docetaxel is an active agent in the treatment of metastatic breast cancer. We evaluated the feasibility of docetaxel-based sequential and combination regimens as adjuvant therapies for patients with node-positive breast cancer.

PATIENTS AND METHODS

Three consecutive groups of patients with node-positive breast cancer or locally-advanced disease, aged < or = 70 years, received one of the following regimens: a) sequential A-->T-->CMF: doxorubicin 75 mg/m2 q 3 weeks x 3, followed by docetaxel 100 mg/m2 q 3 weeks x 3, followed by i.v. CMF days 1 + 8 q 4 weeks x 3; b) sequential accelerated A-->T-->CMF: A and T were administered at the same doses q 2 weeks; c) combination therapy: doxorubicin 50 mg/m2 + docetaxel 75 mg/m2 q 3 weeks x 4, followed by CMF x 4. When indicated, radiotherapy was administered during or after CMF, and tamoxifen started after the end of CMF.

RESULTS

Seventy-nine patients have been treated. Median age was 48 years. A 30% rate of early treatment discontinuation was observed in patients receiving the sequential accelerated therapy (23% during A-->T), due principally to severe skin toxicity. Median relative dose-intensity was 100% in the three treatment arms. The incidence of G3-G4 major toxicities by treated patients, was as follows: skin toxicity a: 5%; b: 27%; c: 0%; stomatitis a: 20%; b: 20%; c: 3%. The incidence of neutropenic fever was a: 30%; b: 13%; c: 48%. After a median follow-up of 18 months, no late toxicity has been reported.

CONCLUSIONS

The accelerated sequential A-->T-->CMF treatment is not feasible due to an excess of skin toxicity. The sequential non accelerated and the combination regimens are feasible and under evaluation in a phase III trial of adjuvant therapy.

Chemotherapy of breast cancer: are the taxanes going to change the natural history of breast cancer?

Among the novel chemotherapeutic drugs introduced in the last decade, taxanes have emerged as the most powerful compounds and results available to date suggest that they will be remembered in the future as the breast cancer chemotherapy of the 1990s. The two taxanes (paclitaxel, Taxol, Bristol-Myers Squibb and docetaxel, Taxotere, Rhône-Poulenc Rorer) share some characteristics, but are also significantly different both in preclinical profile and, most importantly, in clinical characteristics. The main clinical differences are related to their different efficacy-toxicity ratio in relation to dose and schedule; the differing integrability of paclitaxel and docetaxel in anthracycline-taxane containing regimens, secondary to major differences in pharmacokinetic interactions between each taxane and the anthracyclines, and; the potential differences in level of synergism between each taxane and herceptin (HeR2Neu antibody/trastuzumab, Genentech/Roche). In clinical practice, the taxanes are now standard therapy in metastatic breast cancer after prior chemotherapy, in particular anthracyclines, has failed. Their role in combination with anthracyclines in first-line therapy of advanced breast cancer is emerging and sheds new light on the potential role of taxanes in the adjuvant setting. However, the impact of taxanes on the natural history of breast cancer is yet to be defined, despite the trend of results suggesting that these agents have the potential for significant improvements in advanced and, most importantly, adjuvant therapy of breast cancer. The results of all completed or ongoing Phase III trials in first-line metastatic and the adjuvant setting will help determine if taxanes will further improve the outcome of breast cancer or not.