Dose-dense therapy with weekly 1-hour paclitaxel infusions in the treatment of metastatic breast cancer

Weekly paclitaxel in patients with recurrent or persistent advanced ovarian cancer

The purpose of the study is to assess the role of palliative chemotherapy with weekly paclitaxel in patients with persistent or recurrent advanced ovarian cancer. Twenty-eight patients with predominantly paclitaxel- and platinum-resistant ovarian cancer disease were treated with weekly paclitaxel at 80 mg/m2 for 6-8 weeks. In 25 patients (89.2%), this combination represented at least a third line of therapy and for 14 patients (50%) it was more than the fifth line. A clinical response rate of 50% (14 partial responses) was obtained in the 28 patients with evaluable disease. Five patients (17.9%) had stable disease and nine patients (32.1%) had progression of disease. In patients with stable disease or a response, the median progression-free interval was 6 months and overall median survival is 8+ months. All the responses in paclitaxel-resistant tumors were seen in patients with a paclitaxel-free interval of more than 12 months. This regimen is well tolerated with acceptable toxicity. These data suggest that weekly paclitaxel has considerable antitumor activity in heavily pretreated patients with platinum- and paclitaxel-resistant advanced ovarian cancer.

Weekly docetaxel in patients with pretreated metastatic breast cancer: a phase II trial

Docetaxel has consistently demonstrated its high activity as an antineoplastic agent in the treatment of metastatic breast cancer. However, 90% of patients receiving the recommended dose of 100 mg/m2 every 3 weeks will develop grade 3 or 4 neutropenia. Recent data suggest that the safety profile of a weekly docetaxel regimen compared favorably with the standard 3-week schedule. Thus, we initiated a phase II study to assess the efficacy and toxicity of weekly docetaxel in pretreated patients with metastatic breast cancer. Twenty patients with advanced, anthra-cycline-refractory breast cancer were included in this phase II trial. Docetaxel was administered at a starting dose of 40 mg/m2, repeated once a week for 3 consecutive weeks followed by a 1-week rest period (1 cycle). Patients were evaluated for tumor response every 8 weeks (after every other cycle). Therapy was continued for a maximum of six courses in patients showing tumor response or stable disease. Twenty patients received a total of 204 weekly infusions of docetaxel. The mean number of treatments was 10.2 (range 1-18). Eighteen patients were assessable for response. Five patients achieved a partial response and six patients showed either stable disease or a minor response. Seven patients had disease progression. The median survival was 7.8 months. Grade 3/4 leukopenia occurred in two patients. No other grade 3 or 4 hematologic toxicities were observed. The following grade 3/4 non-hematologic toxicities were seen: nausea/vomiting (one patient), infection (one patient), mucositis (two patients) and diarrhea (one patient). Three patients withdrew from the study due to dose-limiting toxicities (one due to severe neutropenia and two due to mucositis). We conclude that administration of docetaxel at a dose of 40 mg/m2 was effective and well tolerated even in heavily pretreated patients with metastatic breast cancer. This regimen is associated with only mild myelosuppression.

Minimizing long-term tumor burden: the logic for metronomic chemotherapeutic dosing and its antiangiogenic basis

The general utility of the maximum tolerated dose (MTD) paradigm, a strategy aimed at optimizing the chance of total tumor cell eradication, is here questioned. Evidence to date suggests that for many tumors the potential for eradication is in fact remote, with patients consistently demonstrating tumor cell presence subsequent to MTD treatments having eradicative intent. The failure to eradicate is attributed largely to the heterogeneous nature of the tumor. Heterogeneous cell populations demonstrate short-term refractoriness to up-front dose delivery, but "resensitize" as part of dose recovery, showing increased overall susceptibility to a given series of doses when delivered more evenly spaced. It is demonstrated: (1) that the minimization of total tumor burden, rather than complete eradication, may often be the more practical objective; and (2) that regularly spaced, "metronomic" dosing is the best way to achieve it. As a corollary, it is found that the more efficient ability of the tumor endothelial cells to resensitize following dosing predicts a targeting bias towards the endothelial compartment of a tumor when metronomic dosing is employed. This lends theoretical support to recent empirical studies showing that regularly spaced dosing schedules with no extended rest periods act more antiangiogenically, thereby delaying or avoiding the onset of acquired resistance.

Weekly oral paclitaxel as first-line treatment in patients with advanced gastric cancer

BACKGROUND

Pharmacokinetic study has shown that co-administration of cyclosporin A (CsA), which acts as a P-glycoprotein (P-gp) and CYP-3A blocker, resulted in an 8-fold increase in the systemic exposure of oral paclitaxel. Two doses of oral paclitaxel on 1 day in combination with CsA resulted in higher systemic exposure than single dose administration.

PATIENTS AND METHODS

In this phase II study, chemonaïve patients with advanced gastric cancer received oral paclitaxel weekly in two doses of 90 mg/m(2) on the same day; CsA (10 mg/kg) was given 30 min before each dose of oral paclitaxel.

RESULTS

In 25 patients, the main toxicities were: nausea CTC grade 2/3, 10 patients (40%); vomiting grade 2/3, 4 patients (20%); diarrhea grade 2/3, 6 patients (24%); neutropenia grade 3/4, 5 patients (20%). In the 24 evaluable patients, eight partial responses were observed, resulting in an overall response rate (ORR) of 33% [95% confidence interval (CI) 18% to 52%]. Eleven patients had stable disease (46%) and 5 patients showed progressive disease (21%). The ORR in the total population was 32% (95% CI 17% to 50%). The median time to progression was 16 weeks (95% CI 9-22). Pharmacokinetic analyses revealed that the mean area under the plasma concentration-time curve (AUC) of orally administered paclitaxel (+/- standard deviation) was 3757.6 +/- 939.4 ng.h/ml in week 1 and 3928.4 +/- 1281 ng.h/ml in week 2. The intrapatient variability in the AUC was 12%.

CONCLUSIONS

Oral paclitaxel in combination with CsA is both active and safe in chemonaïve patients with advanced gastric cancer. Toxicities were mainly gastrointestinal.

Altered clearance of unbound paclitaxel in elderly patients with metastatic breast cancer

The pharmacokinetic behaviour of anticancer drugs may be altered with aging due to (for example) differences in body composition and decreased hepatic and renal function. To address this issue for paclitaxel, we studied the pharmacokinetics of the drug in eight elderly women (>or=70 years) with metastatic breast cancer (median age (range), 77 years (70-84 years)) and a control group of 15 patients aged <70 years (median age (range), 54 years (22-69 years)). Paclitaxel was administered as a 1-h intravenous (i.v.) infusion at a dose of 80 (elderly) or 100 mg/m(2) (<70 years), and serial blood samples were obtained at baseline, and up to 24 h after the end of infusion. Paclitaxel concentration-time profiles were fitted to a linear three-compartment model without any demonstration of saturable behaviour. The clearance of unbound paclitaxel was 124+/-35.0 (elderly) versus 247+/-55.4 l/h/m(2) (<70 years) (P=0.002), and was inversely related to the patient's age (R(2)=0.857; P<0.00001). Total plasma clearance of the formulation vehicle Cremophor EL (CrEL) was 150+/-60.7 (elderly) versus 115+/-39.2 ml/h/m(2) (<70 years) (P=0.04). These data indicate an approximately 50% change in total body clearance of unbound paclitaxel and a concomitant significant increase in systemic exposure with age, most likely as a result of altered CrEL disposition. The clinical relevance of these observations with respect to toxicity profiles and antitumour efficacy requires further evaluation.

A phase II trial of weekly paclitaxel, 5-fluorouracil, and leucovorin as first-line treatment for metastatic breast cancer

PURPOSE

This phase II multicenter trial evaluated the efficacy and toxicity of weekly paclitaxel, 5-fluorouracil, and leucovorin administered as first-line therapy for metastatic breast cancer.

PATIENTS AND METHODS

The study enrolled 155 women with pathologically confirmed and measurable metastatic adenocarcinoma of the breast. Treatment consisted of paclitaxel 80 mg/m2, 5-fluorouracil 425 mg/m2, and leucovorin 20 mg/m2 administered weekly 4 x per 4-week cycle in the first 40 patients enrolled (group 1), and weekly 3 x per 4-week cycle in the subsequent 115 patients (group 2) enrolled. Hematologic growth factor support was not routinely used. Twenty patients with hepatic dysfunction were enrolled to assess the tolerability of the regimen in this population. All therapies were delivered in an outpatient setting.

RESULTS

The overall response rate was 48%, with 12-month estimated survival rates of 53% and 65% for treatment groups 1 and 2, respectively. Response rates were not statistically different between the two treatment schedules. Therapy was well tolerated when delivered on the every 3 of 4-week schedule, including patients with hepatic involvement and those age > or = 65.

CONCLUSION

Weekly therapy with paclitaxel and 5-fluorouracil with leucovorin is active as first-line therapy for metastatic breast cancer. Use of this regimen should be given consideration, particularly in patients who are not candidates for anthracycline-based therapy.

Role of weekly paclitaxel in the treatment of advanced ovarian cancer

Dose-dense weekly administration of paclitaxel has the potential advantage of allowing a larger percentage of cancer cells to enter the vulnerable phase of their cell cycle when cytotoxic paclitaxel concentrations are present. The lower doses and shorter infusion times used with weekly dosing should also minimize bone marrow suppression and other toxicities associated with standard paclitaxel 3-weekly administration. Clinical studies have confirmed that paclitaxel can be safely delivered on a weekly schedule as a 1-h infusion to patients with advanced ovarian cancer. Weekly administration of paclitaxel also appears to be better tolerated than 3-weekly administration. Single-agent weekly paclitaxel is associated with response rates of 20-65%. Combination therapy with weekly paclitaxel has mainly involved carboplatin and response rates with such regimens range from 60-88%. Triple-drug combination therapy has produced response rates of 42-67.5%. Such therapy has included weekly paclitaxel in combination with carboplatin/cisplatin plus topotecan, and carboplatin plus doxorubicin. In an attempt to avoid problems with high corticosteroid doses, dexamethasone doses of 10 and 8 mg have been used successfully in premedication regimens for weekly paclitaxel in ovarian cancer.

Weekly administration of paclitaxel: theoretical and clinical basis

The rationale for weekly administration of paclitaxel, which acts on microtubules to arrest mitosis, is that more frequent delivery of moderate doses may achieve greater efficacy than standard doses every 3 weeks, through more sustained exposure of dividing tumor cells to its cytotoxic effects. This dose-dense approach to treatment may inhibit tumor regrowth between cycles and limit the emergence of malignant cell populations resistant to chemotherapy. More frequent exposure to paclitaxel may also enhance its apoptotic and antiangiogenic effects. Paclitaxel activity is considered to be independent of p53 status, in contrast to anticancer drugs that produce lesions on DNA, which achieve a better response if p53 is functional. Weekly therapy also has advantages in terms of improving paclitaxel therapeutic index. Clinical studies show that weekly paclitaxel is effective and that toxicity is acceptable. The response rates of single-agent paclitaxel varied from 21 to 86% in breast cancer, from 20% to 65% in ovarian cancer and from 30% to 56% in non-small cell lung cancer.

Weekly paclitaxel: an effective and well-tolerated treatment in patients with advanced breast cancer

The rationale for dose-dense weekly paclitaxel in the treatment of breast cancer is that more frequent delivery of more moderate doses may achieve greater efficacy than larger doses given less often through more sustained exposure of dividing tumor cells to cytotoxic drugs. Weekly paclitaxel has been used successfully in the treatment of advanced breast cancer, as single-agent therapy, in combination chemotherapy, with radiotherapy and with immunomodulating drugs, such as trastuzumab. Many of the patients in these studies have received previous chemotherapy regimens. Nevertheless, response rates with weekly paclitaxel up to 86% have been achieved with single-agent therapy, up to 87% with combination therapy and up to 100% when combined with radiotherapy. Paclitaxel given weekly together with the humanized monoclonal antibody against HER2, trastuzumab, has shown response rates of 50-82% in patients with aggressive HER2-positive tumors. Paclitaxel is associated with moderate toxicity. Its main dose-limiting toxicities are neutropenia and peripheral neuropathy, but these are generally manageable.

Weekly paclitaxel in the treatment of metastatic and/or recurrent non-small cell lung cancer

Weekly paclitaxel was initially used to exploit the radiosensitizing properties of the drug. However, the observed improvement in therapeutic index with this regimen encouraged further use of weekly regimens, with and without radiotherapy, as a single-agent or in combination with other regimens. Single-agent weekly paclitaxel, at doses ranging from 50 to 200 mg/m(2)/week, has been associated with response rates of 23-56% with acceptable toxicity. Weekly paclitaxel has also been combined with carboplatin and vinorelbine in two-drug combinations and with cisplatin plus gemcitabine and cisplatin plus vinorelbine in three-drug regimens. Response rates with weekly paclitaxel in combination chemotherapy have ranged from 16 to 71%. Paclitaxel is particularly suited to combined modality therapy with radiation in non-small cell lung cancer, because of its modest toxicity profile, significant antineoplastic activity, ease of administration and potential for radiosensitization. Studies of weekly paclitaxel given together with radiotherapy, with or without carboplatin, have produced response rates of 71-86% with median survival durations of 17-20.5 months.

Critical review of current treatment strategies for advanced hormone insensitive breast cancer

Breast cancer is the most common cancer diagnosis in American women. Over the past several decades, there has been a steady increase in the incidence of this disease. Fortunately, the death rates in the last decade has showed a decrease. Patients with breast cancer now have more treatment options and a better chance of long term survival than ever before. Patients with metastatic disease are considered candidates for chemotherapy if they are symptomatic, have rapidly progressing or bulky disease, or if they are inappropriate candidates for hormonal therapy either because of negative hormonal receptor status or progression of disease on hormonal therapies. Patients are often treated with a chemotherapy regimen until progression of disease, or prohibitive toxicity, at which time the therapy is changed to a second or a third line therapy. This manuscript will provide a review of the current treatment strategies for advanced hormone insensitive breast cancer.

Phase II and pharmacologic study of weekly oral paclitaxel plus cyclosporine in patients with advanced non-small-cell lung cancer

PURPOSE

A phase II study was performed to assess the efficacy and toxicity of oral cyclosporine (CsA) plus paclitaxel in advanced non-small-cell lung cancer (NSCLC).

PATIENTS AND METHODS

Chemotherapy-naive or previously treated patients (one regimen) with measurable disease and World Health Organization performance status <or= 2 were eligible. Oral paclitaxel was given weekly in a dose of 90 mg/m(2) bid. CsA (10 mg/kg) was given 30 minutes before each dose of oral paclitaxel.

RESULTS

Twenty-six patients with a median age of 54 years (range, 32 to 77 years) were entered onto this study. Eighteen patients (69%) had received one prior chemotherapy regimen. The most frequently recorded toxicities were as follows: National Cancer Institute common toxicity criteria grade 3 neutropenia, eight patients (31%); grade 4, six patients (23%); grade 4 febrile neutropenia, three patients (12%); grade 2/3 neurotoxicity, three patients (12%); and grade 2 nail changes, four patients (15%). The overall response rate (ORR) of the 23 assessable patients was 26% (95% confidence interval [CI], 10% to 48%). In the intention-to-treat population, the ORR was 23% (95% CI, 9% to 44%). The median time to progression was 3.5 months (95% CI, 1.2 to 3.9 months), and median overall survival was 6.0 months (95% CI, 2.3 months to not available). Pharmacokinetics revealed that the mean area under the concentration-time curve (AUC) of oral paclitaxel was 5.0 +/- 2.3 micro mol/L/h in week 1 and 4.6 +/- 2.0 micro mol/L/h in week 2, with interpatient variabilities (coefficient of variation [%CV]) of 45% and 42%, respectively. The intrapatient variability (%CV) of the AUC was 14.5%.

CONCLUSION

Oral paclitaxel plus CsA is active and safe in advanced NSCLC, including in patients previously treated with chemotherapy.

Weekly docetaxel/paclitaxel in pretreated metastatic breast cancer

The purpose of our study was to evaluate the feasibility and efficacy of weekly docetaxel/paclitaxel in pretreated advanced breast cancer patients. Twenty-six patients with metastatic breast cancer were included in this study. Three different schedules of treatment were administered. The starting schedule, A1, consisted of docetaxel 60 mg/m2 on day 1 plus paclitaxel 60 mg/m2 over 1 hour, weekly for 18 weeks; this schedule was considered feasible if at least 70% of the planned doses were given on time and without reduction. Schedule A2 consisted of the same doses administered on days 1 and 8 every 3 weeks, and schedule B consisted of docetaxel 25 mg/m2 followed by paclitaxel 40 mg/m2 for 1 hour on days 1 and 8 every 3 weeks for a total of 6 cycles. All patients had received prior anthracyclines, and 19 patients were pretreated with taxanes. Seventy-seven percent of patients had received at least 2 prior lines of chemotherapy. Twenty-five patients are assessable for toxicity and efficacy. A total of 109 cycles of chemotherapy have been administered, with a median of 4 cycles per patient (range, 1-8 cycles). The median delivered dose intensity was 27 mg/m2/week for paclitaxel (range, 18-50 mg/m2/week) and 17 mg/m2/week (range, 12-39 mg/m2/week) for docetaxel. Six patients received schedule A1. This schedule was considered not feasible due to neutropenia grade > 2, mucositis, and diarrhea grade 2, which required dose reduction/omission in 33% of administrations. For this reason, treatment in the following 5 patients was omitted on day 15 (schedule A2). Schedule B was found to be more feasible with 16% of dose reductions/omissions. The overall response rate was 68% (95% CI, 50%-86%) with a median duration of response of 10 months (range, 2-18+ months). Treatment was well tolerated; myelosuppression was rare and grade 3 cutaneous toxicity was observed in only 2 patients. In conclusion, weekly docetaxel/paclitaxel is active at low dosages and was well tolerated as salvage chemotherapy in metastatic breast cancer. This regimen represents a valid option as a salvage treatment in taxane- and anthracycline-pretreated patients.

Ongoing US cooperative group trials using taxanes in the adjuvant setting

The use of systemic adjuvant therapy in women with early-stage breast cancer has been demonstrated to have a profound impact on survival. The role of paclitaxel and docetaxel in the adjuvant setting has attracted a great deal of attention. Both of these agents are highly active in patients with advanced breast cancer. In addition, they can be utilized in combination with anthracyclines, which have been shown to provide a slightly better outcome in patients with early-stage breast cancer compared to non-anthracycline-containing regimens. Randomized trials have demonstrated a potential role for paclitaxel in adjuvant chemotherapy. In the Cancer and Leukemia Group B 9344 trial, which explored the use of doxorubicin and cyclophosphamide with or without paclitaxel, the initial analysis demonstrated a 22% reduction in the relative risk of relapse and a 26% reduction in the relative risk of death in the paclitaxel group. However, a clear role for the use of paclitaxel in adjuvant therapy remains to be defined. The Breast Cancer International Research Group trial 001 compared the combination of docetaxel/doxorubicin/cyclophosphamide to 5-fluorouracil/doxorubicin/cyclophosphamide. This trial demonstrated a promising reduction in the relative risk of recurrence of 32% for the docetaxel/doxorubicin/cyclophosphamide group. Ongoing trials will help to further define the role of taxanes in the adjuvant setting for patients with operable breast cancer.

Successful treatment of post-renal transplant Kaposi's sarcoma with paclitaxel

Kaposi's sarcoma (KS) is a complication of immunosuppressive therapy for renal transplant recipients. Treatment is usually withdrawal of immunosuppression; nonresponders often receive chemotherapy. Successful treatment with single agent paclitaxel (PTX) has been documented in only one patient. We report two patients with generalized cutaneous, and visceral KS, which progressed despite withdrawal of immunosuppressive therapy, and were treated with weekly PTX. Both patients' KS regressed completely after four courses of PTX, and remained in remission for > 1 year. PTX may be important in the treatment of post-transplant KS resistant to withdrawal of immunosuppressive therapy.

Phase II multicenter trial of a weekly paclitaxel and carboplatin regimen in patients with advanced breast cancer

PURPOSE

To determine the activity of weekly paclitaxel plus carboplatin as first-line therapy in patients with advanced breast cancer (ABC) by assessing response rate, survival, and safety.

PATIENTS AND METHODS

One hundred patients with ABC received paclitaxel 135 mg/m(2) (group 1, n = 20) and carboplatin area under the concentration-time curve (AUC) of 2. Paclitaxel was subsequently reduced to 100 mg/m(2) (group 2, n = 80) because of toxicity. The median age was 58.5 years, and most patients had an Eastern Cooperative Oncology Group performance status of <or= 2. Estrogen and progesterone receptor status were evenly distributed among both groups. Sixty-one patients received prior chemotherapy, 37 (61%) of whom received prior doxorubicin. Among 47 patients who received prior hormonal therapy, 43 received tamoxifen.

RESULTS

The overall response rate (ORR) among 95 assessable patients was 62%, including 8% complete responses and 54% partial responses. The median time to response was 1.8 months, and the median duration of response was 13.3 months. The median time to progression was 4.8 months. The median survival was 16 months. Neutropenia and leukopenia were the most common grade 3 and 4 toxicities. In group 1, neutropenia (50%) and leukopenia (35%) necessitated dose reductions for 50% of patients during the first three cycles, prompting the reduction in paclitaxel dose to 100 mg/m(2). Grade 3 and 4 nonhematologic toxicities for all patients included peripheral neuropathy (11%), infection (6%), anemia (5%), weakness (6%), and paresthesia (3%).

CONCLUSION

The 62% ORR achieved with weekly paclitaxel plus carboplatin is among the highest achieved with chemotherapy for ABC. This high response rate and the lack of cardiotoxicity suggest that the regimen should be considered as a nonanthracycline regimen for future adjuvant therapy.

Prospective exploratory analysis of the association between tumor response, quality of life, and expenditures among patients receiving paclitaxel monotherapy for refractory metastatic breast cancer

PURPOSE

To prospectively evaluate the association between tumor response, change in quality of life (QoL), and hospital expenditures in patients with metastatic breast cancer (MBC) receiving single-agent paclitaxel.

PATIENTS AND METHODS

Eligible patients had bidimensionally measurable MBC and any number of previous therapies, excluding taxane chemotherapy. Paclitaxel was administered by various different infusion schedules. QoL measures were evaluated for each patient at baseline and serially using the Memorial Symptom Assessment Scale (MSAS)-Global Distress Index (GDI) and Functional Assessment of Cancer Therapy-Breast (FACT-B) instruments. Patients were assessed for early (first 6 weeks) and ever changes in QoL parameters. Charges were monitored through the hospital's centralized computer billing system and converted to cost ratios for the analysis. Correlations between response and improvement in QoL were assessed by Fisher's exact test statistic. Associations between improvements in QoL with cost ratios were assessed by logistic regression and likewise between response and cost ratios.

RESULTS

Of the 59 patients treated, 50 had sufficient data for comparative analyses. The overall response rate was 24% (all partial responses). Minor responses were observed in 17% of patients, 25% had stable disease, and 29% had progression. Responding patients had significant improvement in QoL as assessed by MSAS-GDI (P =.004) and FACT-B (P =.028). The mean total cost/month ratios for patients experiencing improved GDI QoL scores was 1.31 versus 1.56 for those without QoL benefit (P =.52) and 1.05 versus 1.76 for responders versus nonresponders, respectively (P =.07).

CONCLUSION

Patients with evidence of tumor response on paclitaxel had a QoL benefit not observed in nonresponders, and this response was associated with a trend for lower overall costs.

Which dosing scheme is suitable for the taxanes? An in vitro model

The discovery and development of the taxane class of antitumor compounds represent significant advances in the treatment of patients with a variety of malignancies. These drugs are effectively used in the treatment of breast cancer. In this study we evaluated the efficacy of fractionated usage of both paclitaxel and docetaxel as a single agent in the breast cancer cell line MCF-7. It has been shown that the cytotoxic effect of paclitaxel was increased when the divided IC50 concentrations were used sequentially and in contrast to paclitaxel, cytotoxic effect of docetaxel was decreased with the same schema and the single dose of IC50 concentration was optimal. The cause of the difference between the cytotoxic effects of two agents with this schedule is obscure. Demonstrating mechanisms, which are responsible for these differences, will be important for more rational use of taxoids and to provide basis for the following clinical trials.

Phase II trial of Paclitaxel and Dacarbazine with filgrastim administration in advanced malignant melanoma

A Phase II trial was conducted in patients with advanced malignant melanoma with intravenous Paclitaxel and Dacarbazine (DTIC). The initial starting dose for Paclitaxel was 135 mg/m2 followed by DTIC 800 mg/m2. Due to the lack of myelosuppression and other toxicities, the starting dose for Paclitaxel was escalated to 250 mg/m2 and the dose for DTIC escalated to 1000 mg/m2. Twenty-five patients were enrolled in this study. Among the 25 patients assessable for response, three patients had a partial response with a response rate of 12% (CI 3-31%) and one patient had stable disease. Three additional patients showed evidence of anti-tumor activity with minor responses. For patients who had no prior chemotherapy or biochemotherapy, the response rate was 20%. Toxicity was generally tolerable and included mainly neurotoxicity from Paclitaxel. At the doses and schedule used, the combination of Paclitaxel and DTIC did not appear to increase the response rate compared to each agent used singly.

Pharmacodynamics of non-break weekly paclitaxel (Taxol) and pharmacokinetics of Cremophor-EL vehicle: results of a dose-escalation study

We characterized the toxicity and determined the maximum tolerated dose of non-break weekly paclitaxel (Taxol) in chemotherapy-naive cancer patients, and studied pharmacokinetics of the formulation vehicle Cremophor-EL with this schedule. Twenty-three patients with primary refractory solid tumors received weekly paclitaxel at the dose range of 70-200 mg/m2. As dose-limiting toxicity we defined granulocytopenia grade > or =2 causing a treatment delay for more than 2 weeks, or febrile neutropenia or grade >2 organ-specific toxicity. Plasma kinetics of Cremophor-EL were analyzed over the first five courses of treatment. Non-break weekly paclitaxel was feasible at doses up to 110 mg/m2, while granulocytopenia precluded scheduled administration of doses > or =130 mg/m2. Clinically relevant peripheral neurotoxicity tended to occur at around 1500 mg/m2 cumulative dosage at weekly doses > or =110 mg/m2. Detectable Cremophor-EL levels were found in all pre-dose samples, but there was no evidence of accumulation up to the sixth course. Our results, discussed in the light of an overview of published data, suggest that chronic weekly administration of paclitaxel is feasible and with a lack of significant accumulation of Cremophor-EL levels at doses up to 90 mg/m2.

First-line chemotherapy with weekly paclitaxel and carboplatin for advanced ovarian cancer: a phase I study

OBJECTIVES

Carboplatin and paclitaxel can be applied safely and effectively as single agents for the treatment of ovarian cancer on a weekly basis. A multicenter, phase-I study was conducted to investigate the maximum tolerated dose of a weekly combination regimen.

METHODS

We enrolled 21 patients with primary, surgically resected, advanced ovarian cancer (FIGO III/ IV) and a median age of 59 (range, 35 to 79) years. For a fixed dose of paclitaxel at 100 mg/m(2), carboplatin was administered at levels equating an area under the curve of 2.0 (6 patients), 2.5 (7 patients), and 3.0 (8 patients), respectively. Treatment schedule consisted of six cycles with drug delivery once a week, followed by a 2-week break, and another six cycles. After a treatment-free interval of 28 days, three more cycles were administered.

RESULTS

No dose-limiting toxicity was observed at the first level. Three patients developed dose-limiting toxicity (thrombocytopenia, neutropenic fever, and grade 3 neuropathy) receiving carboplatin at area under the curve 2.5. Another three patients developed dose-limiting toxicity at the highest carboplatin dose, of whom two encountered refractory thrombocytopenia, whereas another experienced neutropenic fever despite prophylactic granulocyte-colony-stimulating factor use. Alopecia was documented in 17 patients. Neurotoxicity was usually mild to moderate. CA-125 concentrations normalized (<35 U/ml) in 13 of 19 patients (68%) by the end of therapy. A 50% response was observed in 16 of 19 subjects.

CONCLUSIONS

Weekly carboplatin and paclitaxel is a well-tolerated combination regimen in patients with primary, advanced ovarian cancer. The recommended dose for a phase II study is carboplatin at 100 mg/m(2) and carboplatin at area under the curve 2.0.

The Role of Weekly Docetaxel in the Treatment of Advanced non—small-Cell Lung Cancer

Docetaxel is one of the most active single agents in the treatment of advanced non-small-cell lung cancer (NSCLC). Weekly administration of docetaxel markedly reduces myelosuppression and also reduces nonhematologic toxicity. Phase II trials with single-agent weekly docetaxel have been completed in first- and second-line treatment of advanced NSCLC; preliminary results of treatment with weekly docetaxel-based combination regimens are also available. In patients who were elderly or had poor performance status, weekly docetaxel produced a 19% response rate, 28% 1-year survival, and was well tolerated. As second-line therapy, response rates to weekly docetaxel were similar to results with administration every 3 weeks, although no direct comparisons exist. Combination regimens, particularly weekly docetaxel/gemcitabine, also appear active and well tolerated and should be further evaluated. Addition of various targeted agents (eg, epidermal growth factor receptor inhibitors, antiangiogenesis agents) also merits evaluation.

Weekly paclitaxel in women age 65 and above with metastatic breast cancer

We evaluated therapy with weekly paclitaxel 80 mg/m2 in metastatic breast cancer patients age > or =65. There was a low incidence of serious toxicities, with similar tolerability profiles in younger and older patients. Response rates and overall survival times were comparable in the two age groups (<65 and > or =65). Weekly paclitaxel therapy is a reasonable option for older patients with metastatic breast cancer.

Genetic protection of repopulating hematopoietic cells with an improved MDR1-retrovirus allows administration of intensified chemotherapy following stem cell transplantation in mice

This study was undertaken to analyze the hematotoxicity of paclitaxel (Taxol) and to test whether transduction of repopulating hematopoietic cells with a retroviral vector (SF1m) expressing the human multidrug resistance 1 gene (MDR1) would permit dose intensification following bone marrow transplantation (BMT). While the regimen chosen (8 x 20 mg/kg i.p. within 12 days) produced a non-lethal, reversible hematotoxicity in mice with steady-state hematopoiesis, only 35.3% (6/17) of control mice survived when treated starting 14 days post BMT. In contrast, 83.3% (15/18) of mice transplanted with SF1m-transduced cells survived, owing to a significant protection against severe acute myelotoxicity (as determined by neutrophil counts, white and red blood cell counts and values for hemoglobin and hematocrit). After recovery from chemotherapy, an increase of myeloid cells that were resistant to colchicine and effluxed the fluorochrome Rhodamine 123 was observed in SF1m-mice, but not in controls. These results reveal that the lethal, dose-limiting hematotoxicity of an intensified post-transplantation chemotherapy with paclitaxel can be prevented by retroviral transfer of the MDR1 gene to a minor proportion of repopulating cells. Our mouse model, mimicking clinically achievable gene transfer rates, thus suggests that bone marrow chemoprotection may widen the therapeutic window and permit an earlier onset of post-transplantation chemotherapy.

Phase II trial of weekly paclitaxel in patients with previously treated advanced urothelial cancer

PURPOSE

We evaluated the efficacy and toxicity of weekly paclitaxel in patients with previously treated advanced urothelial cancer.

PATIENTS AND METHODS

Patients with urothelial cancer who had received one prior systemic chemotherapy regimen for advanced disease and had evidence of disease progression were eligible for enrollment. Patients received paclitaxel 80 mg/m(2) by 1-hour intravenous infusion weekly. A cycle of therapy consisted of four weekly treatments.

RESULTS

The study enrolled 31 patients. Mean age was 66 years, and 45% of patients had three or more involved metastatic sites. Only 26% of patients had responded to prior chemotherapy. The median number of cycles delivered was three (range, one to eight) at a mean weekly paclitaxel dose of 79 mg/m(2). Three patients achieved a partial response (10%; 95% confidence interval, 0% to 20%). Median time to progression was 2.2 months, and median overall survival time was 7.2 months. Therapy was well tolerated with minimal hematologic toxicity. Grade 3 nonhematologic toxicities were also uncommon.

CONCLUSION

Although the overall response rate to weekly paclitaxel in patients with previously treated advanced urothelial cancer was modest, the chemotherapy-refractory nature of the study population should be considered.

Phase II study of weekly docetaxel in patients with metastatic breast cancer

BACKGROUND

This study was conducted to investigate the efficacy and toxicity of weekly docetaxel administration in patients with metastatic breast cancer.

PATIENTS AND METHODS

Thirty-seven women were treated with 1 h infusions of docetaxel at 40 mg/m2/week after pre-medication with 8 mg dexamethazone. Each cycle consisted of three consecutive weekly treatments followed by a 1 week rest. All patients were assessed for toxicity; five patients were not assessable for clinical response, time to progression (TTP) and overall survival (OS) because of early treatment failure, but they were included in intention-to-treat analysis.

RESULTS

Patients received a median of four cycles (range, 1-9), with a median dose intensity of 28 mg/m2/week (range 22-30) and a median relative dose intensity of 0.95 (range 0.73-1.0). No patients showed complete response, whereas 14 had partial response, which accounted for 38% of objective response rate [95% confidence interval (CI) 22% to 53%]. In addition, three patients (8%, 95% CI 0% to 17%) had stable disease over 6 months. Clinical responses were achieved at a median of three cycles (range 1-4 cycles). The median TTP and OS were 5 and 12 months, respectively. The weekly docetaxel regimen was generally well tolerated. About half of the patients experienced grade > or = 1 neutropenia; only 19% had grade 3/4 neutropenia, including one case of grade 4. No febrile neutropenia was observed and fluid retention syndrome was uncommon. Non-hematologic toxicity, however, such as asthenia/fatigue, nail damage, tearing or hearing disorders, was seen with successive treatment cycles.

CONCLUSIONS

Weekly docetaxel at 40 mg/m2/week is an active and feasible regimen for patients with metastatic breast cancer.

Comparative pharmacokinetics of unbound paclitaxel during 1- and 3-hour infusions

PURPOSE

The paclitaxel vehicle Cremophor EL (CrEL) profoundly influences the cellular distribution of paclitaxel in human blood in vitro by a concentration-dependent decrease of the unbound drug fraction. Because CrEL clearance increases by extending the infusion duration from 3 to 24 hours, we hypothesized that exposure to unbound paclitaxel might also be schedule-dependent.

PATIENTS AND METHODS

CrEL and unbound paclitaxel pharmacokinetics were prospectively analyzed in 29 patients with advanced solid tumors treated with paclitaxel 100 mg/m(2) given as a 1-hour (n = 15) or 3-hour (n = 14) intravenous infusion.

RESULTS

The systemic exposure (area under the curve [AUC]) to CrEL was significantly higher with the 1-hour as compared with the 3-hour schedule (80.2 +/- 24.2 v. 48.5 +/- 24.1 microL x h/mL; P =.002). In contrast, the AUC of unbound paclitaxel was substantially reduced after the 1-hour infusion (0.50 +/- 0.10 v. 0.62 +/- 0.12 micromol/L x h; P =.009). Similarly, clearance and volume of distribution were significantly dependent on infusion duration (P <.005). A trend was observed toward more severe hematologic toxicity with the 3-hour schedule (P =.053), consistent with increased exposure to unbound drug.

CONCLUSION

Overall, these findings explain, at least in part, previous observations that short-infusion schedules of paclitaxel lack significant myelotoxicity, whereas potentially CrEL-related side effects, including peripheral neuropathy, are augmented.

Metronomic scheduling: the future of chemotherapy?

Tumour endothelium is a new target for anticancer treatments. Proliferating endothelial cells from the tumour, even if qualitatively different from those of blood vessels in the normal tissue of origin, remain putatively normal and genetically stable cells. The results of recent experimental studies have suggested that frequent administration of certain cytotoxic agents at low doses (a tenth to a third of the maximum tolerated dose), known as 'metronomic' chemotherapy, increases the antiangiogenic activity of the drugs. The effects of these metronomic schedules of cytotoxic agents may be further enhanced by concurrent administration of novel, selective, treatments that inhibit, at a molecular level, the processes of tumour formation and growth eg angiogenesis, growth factor pathways, and other signal transduction cascades. The need to treat patients for long periods also supports the use of metronomic scheduling for chemotherapy, to minimise toxicity and to target both proliferating tumour cells and endothelial cells. This review describes the experimental studies involving metronomic schedules of chemotherapy, alone and in combination with angiogenesis inhibitors, and suggests a new therapeutic anticancer paradigm for controlling cancer by long-term therapy, based on the development of combinations of metronomic cytotoxic agents with individually tailored compounds designed to target specific molecules.

Multicenter phase II trial of weekly paclitaxel in women with metastatic breast cancer

PURPOSE

We evaluated the safety and efficacy of weekly paclitaxel therapy in women with metastatic breast cancer in a phase II multicenter trial. Entry criteria were relatively liberal to reflect the heterogeneity of metastatic breast cancer in clinical practice.

PATIENTS AND METHODS

Patients had histologically confirmed and measurable metastatic breast cancer. Up to two prior chemotherapy regimens for metastatic disease, including prior therapy with anthracyclines and taxanes and prior high-dose therapy, were allowed. Paclitaxel 80 mg/m(2) was administered weekly for 4 weeks per 4-week cycle.

RESULTS

We enrolled 212 patients; 211 were assessable for toxicity and 177 were assessable for response. Ninety percent of patients had received prior chemotherapy (adjuvant, metastatic, or both), 46% of patients had three or more involved metastatic sites, and 60% of patients had visceral-dominant disease. Responses were documented on two occasions and were independently reviewed. The overall response rate (complete plus partial response) was 21.5% (95% confidence interval, 15.4% to 27.5%), with 41.8% of patients having disease stabilization. Median time to progression was 4.7 months, and overall survival in all 212 patients enrolled was 12.8 months. Therapy was well tolerated, with a 15% incidence of grade 3/4 hematologic toxicity and a 9% incidence of grade 3 neurotoxicity; other serious toxicities were rare. The response rate and toxicity profile in the 34% of patients > or = 65 years of age were similar to that of younger patients.

CONCLUSION

Weekly paclitaxel therapy was well tolerated and demonstrated reasonable activity in this relatively heavily pretreated population with advanced disease. Further study of weekly paclitaxel in combination therapy is warranted.

Weekly paclitaxel as first-line chemotherapy and trastuzumab in patients with advanced breast cancer. A Hellenic Cooperative Oncology Group phase II study

AIM

To evaluate the activity and acute toxicity of the combination of weekly paclitaxel as first-line chemotherapy and trastuzumab, in patients with HER-2/neu overexpressing advanced breast cancer (ABC).

BACKGROUND

Weekly paclitaxel has been shown to be a well tolerated treatment with considerable activity in patients with ABC. Clinical trials with transtuzumab, a humanized anti-p185 HER-2/neu monoclonal antibody have demonstrated that this agent produces objective responses in patients with ABC.

PATIENTS AND METHODS

From December 1998 to April 2000, 34 patients with HER-2/neu overexpressing ABC were treated with weekly paclitaxel; given by one-hour infusion at a dose of 90 mg/m2 immediately followed by trastuzumab, 4 mg/kg as a loading dose and 2 mg/kg i.v. given over 30 min, thereafter weekly for at least 12 weeks. Expression of HER-2/neu was determined by immunohistochemical analysis on fixed, paraffin-embedded tissues. Eligible patients were required to have > or = 25% stained tumor cells.

RESULTS

Thirty-three patients completed at least 12 weeks of combined treatment. After completion of the 12th week of treatment, four patients (12%) achieved complete and 17 (50%) partial response. Median duration of response was 11.6 months. More frequent side effects included anemia (56%). neutropenia (27%), peripheral neuropathy (78%), diarrhea (30%), alopecia (70%), arthralgias/myalgias (62%), fatigue (59%) and hypersensitivity reactions (62%). Median time to progression was nine months while median survival had not been reached

CONCLUSIONS

The combination of weekly paclitaxel and trastuzumab is a safe and active regimen for patients with HER-2/neu overexpressing ABC. Randomized phase III studies with this combination are warranted.

Drug distribution and pharmacokinetic/pharmacodynamic relationship of paclitaxel and gemcitabine in patients with non-small-cell lung cancer

BACKGROUND

Gemcitabine and paclitaxel are two of the most active agents in non-small-cell lung cancer (NSCLC), and pharmacologic investigation of the combination regimens including these drugs may offer a valuable opportunity in treatment optimization. The present study investigates the pharmacokinetics and pharmacodynamics of paclitaxel and gemcitabine in chemotherapy-naive patients with advanced NSCLC within a phase I study.

PATIENTS AND METHODS

Patients were given i.v. paclitaxel 100 mg/m2 by one-hour infusion followed by gemcitabine 1,500, 1,750 and 2,000 mg/m2 by 30-min administration. Plasma levels of paclitaxel, gemcitabine and its metabolite 2',2'-difluorodeoxyuridine (dFdU) were determined by high-performance liquid chromatography (HPLC). Concentration-time curves were modeled by compartmental and non-compartmental methods and pharmacokinetic/pharmacodynamic (PK/PD) relationships were fitted according to a sigmoid maximum effect (Emax) model.

RESULTS

Paclitaxel pharmacokinetics did not change as a result of dosage escalation of gemcitabine from 1,500 to 2,000 mg/m2. A nonproportional increase in gemcitabine peak plasma levels (Cmax, from 18.56 +/- 4.94 to 40.85 +/- 14.85 microg/ml) and area under the plasma concentration-time curve (AUC, from 9.99 +/- 2.75 to 25.01 +/- 9.87 h x microg/ml) at 1,500 and 2,000 mg/m, respectively, was observed, suggesting the occurrence of saturation kinetics at higher doses. A significant relationship between neutropenia and time of paclitaxel plasma levels > or = 0.05 micromol/l was observed, with a predicted time of 10.4 h to decrease cell count by 50%. A correlation was also observed between percentage reduction of platelet count and gemcitabine Cmax, with a predicted effective concentration to induce a 50% decrease of 14.3 microg/ml.

CONCLUSION

This study demonstrates the lack of interaction between drugs, the nonproportional pharmacokinetics of gemcitabine at higher doses and the Emax relationship of paclitaxel and gemcitabine with neutrophil and platelet counts, respectively. In addition, gemcitabine 1,500 mg/m2 is the recommended dosage in combination with paclitaxel 100 mg/m2 for future phase II studies, due to its predictable kinetic behaviour and less severe thrombocytopenia than expected.

Paclitaxel in the multimodality treatment for inflammatory breast carcinoma

BACKGROUND

Inflammatory breast carcinoma (IBC) is a rare but aggressive form of breast carcinoma. Anthracycline-based regimens represent the standard of treatment for IBC. Reports of significant clinical activity of paclitaxel in metastatic breast carcinoma led the authors to investigate the role of this drug in the management of IBC.

METHODS

Forty-four patients with IBC were enrolled between February 1994 and January 1998. The treatment plan consisted of induction chemotherapy (IC), mastectomy, adjuvant chemotherapy, and radiotherapy. Forty-two patients received IC with four cycles of fluorouracil, doxorubicin, and cyclophosphamide. If the clinical response was less than partial, patients were "crossed over" to paclitaxel before mastectomy. All patients received adjuvant paclitaxel. Patients unresectable after paclitaxel were offered high-dose chemotherapy with autologous peripheral blood progenitor cell support.

RESULTS

Thirty-four patients (81%) achieved an objective clinical remission; 3 patients (7%) achieved a clinical complete remission, 31 (74%) a partial remission. Six patients (14%) achieved pathologic complete remission. Sixteen patients were treated with paclitaxel, 7 of them (44%) were able to undergo mastectomy. Median time to progression (TTP) was 22 months. Median overall survival (OS) was 46 months. Concordance between clinical and pathologic response was documented in only 8 patients (24%). No differences in TTP and OS compared with a historical group of 178 IBC patients treated with anthracycline-based regimens.

CONCLUSIONS

Paclitaxel improves tumor resectability in anthracycline-refractory IBC. The impact of paclitaxel on the prognosis of IBC needs to be better evaluated in future trials using more dose-intensive schedules of administration. New imaging modalities may contribute to improve assessment of response to IC.

An analysis of relapsed breast cancer in patients previously treated with breast conserving surgery

BACKGROUND

Recent advances in breast surgery have focused on breast conserving surgery in combination with radiotherapy. In the present study, we examine by retrospective analysis 105 patients with breast cancer who received breast conserving surgery for factors influencing disease free survival.

METHODS

The analysis was performed on 105 patients with breast cancer who received breast conserving surgery in our department, including 38 patients without radiotherapy and 67 patients treated with radiotherapy. The disease-free survival of the patients was analyzed using the Kaplan-Meier method. The relapsed patients were assessed by examining pathological features and gene expression by immunohistochemical staining.

RESULTS

There was no significant difference in the disease free survival at 5 years between patients without radiotherapy (89.6%) and with radiotherapy (94.5%). Relapse after breast conserving surgery was found in 6 patients including 4 patients without radiotherapy and 2 patients with radiotherapy. Local relapse and bone metastasis were found in 4 (3.8%) and 2 patients, respectively. Among the 4 local relapses, 1 patient had received radiotherapy and 3 patients had not. There was no significant difference between the type of relapse in terms of lymph node metastasis, hormone receptor, nuclear grade and intraductal component, but more vessel invasion was observed in the 2 cases with bone metastasis. The overexpression of apoptosis and angiogenesis genes such as p53, Bax, Bcl-XL, Bcl-2 and VEGF was not common in the relapsed patients, whereas the overexpression of drug resistance genes, either P-gp or MRP1, was found in the all patients.

CONCLUSIONS

Although radiotherapy may reduce the incidence of local relapse and increase disease free survival after breast conserving surgery, the development of an effective adjuvant chemotherapy based on drug resistance markers, is also required.

A Phase I-II study of 96-hour infusional topotecan and paclitaxel for patients with recurrent Müllerian tumors

BACKGROUND

Topotecan and paclitaxel are schedule dependent chemotherapeutic agents with activity against ovarian carcinoma. A Phase I-II study in which both drugs were administered concurrently by 96-hour, continuous, intravenous infusion was performed to determine the maximum tolerated dose (MTD), toxicities, pharmacokinetics, and efficacy of the combination.

METHODS

Women with ovarian or primary peritoneal carcinoma and documented recurrent disease were eligible for the study. The dose of topotecan was escalated from 1.6 mg/m(2) while maintaining the paclitaxel dose constant at 100 mg/m(2). Plasma concentrations of both drugs were monitored daily during the first cycle of therapy.

RESULTS

Forty-five patients with a median age of 54 years (range, 42-70 years) received 181 cycles of therapy. Five patients were recruited to each of four dose levels (topotecan 1.6 mg/m(2), 2.0 mg/m(2), 2.8 mg/m(2), and 3.6 mg/m(2)), and an additional 25 patients were treated at the MTD (Phase II). Neutropenia and thrombocytopenia became dose limiting toxicities (DLT) at the fourth dose level. Emesis, mucositis, peripheral neuropathy, diarrhea, and alopecia were mild. Twenty patients (44%) had line-related occlusion, thrombosis, or infection. The mean values (+/- standard deviation) of the apparent steady-state plasma concentrations at the Phase II doses were 2.3 nM +/- 0.5 nM for topotecan lactone, 5.6 nM +/- 2.1 nM for total topotecan, and 40.1 nM +/- 16.8 nM for paclitaxel. There were seven partial responses (Phase II) contributing to an objective response rate of 28% and a median survival time of 11.7 months (range, 0.6-20.1 months).

CONCLUSIONS

Topotecan at a dose of 2.8 mg/m(2) and paclitaxel at a dose of 100 mg/m(2) administered by concurrent, 96-hour, continuous intravenous infusions shows activity against tumors of Müllerian origin.

Weekly docetaxel in the treatment of elderly patients with advanced breast cancer: a Minnie Pearl Cancer Research Network phase II trial

PURPOSE

To evaluate the efficacy and toxicity of docetaxel administered weekly to elderly or poor-performance status patients with advanced breast cancer.

PATIENTS AND METHODS

Forty-one patients with advanced breast cancer who were either over the age of 65 or considered to be poor candidates for combination chemotherapy received docetaxel 36 mg/m2 weekly for 6 consecutive weeks, followed by 2 weeks without treatment. The median age of patients in this trial was 74 years, and 73% of patients had one or more visceral sites of metastases. Seventy-five percent of patients received weekly docetaxel as first-line treatment for metastatic breast cancer, and the other 25% received it as second-line treatment. Thirty-six patients were assessable for efficacy, and all patients were assessed for toxicity.

RESULTS

A total of 448 doses of weekly docetaxel were administered to 41 patients. Thirteen patients (36%) had objective responses to treatment, and an additional 13 patients (36%) had stable disease or minor response. Median time to progression for responding and stable patients was 7 months (range, 3 to 27 months). Median survival for the entire group was 13 months, with 1- and 2-year actuarial survival rates of 61% and 29%, respectively. Severe neutropenia occurred in only 0.4% of courses, and no other hematologic toxicity was observed. Grade 3/4 fatigue was the most common toxicity, occurring in 20% of patients.

CONCLUSION

Weekly docetaxel therapy is active and well tolerated by elderly and/or poor-performance status patients with advanced breast cancer. This treatment can be administered with minimal myelosuppression. Weekly docetaxel provides an additional option for treatment in this difficult subgroup of patients with metastatic breast cancer. Well-tolerated combination regimens containing weekly docetaxel merit evaluation for this patient population.

Weekly docetaxel in breast cancer: applying clinical data to patient therapy

The use of weekly 35-40 mg/m2 docetaxel, typically on a schedule of 6 weeks of therapy followed by a 2-week break, has produced response rates ranging from 33%-50% in patients with advanced breast cancer, the majority of whom have already received chemotherapy. These encouraging levels of response are seen across disease sites and in patients with prior anthracycline exposure. Importantly, the weekly administration of docetaxel allows prolonged treatment to a high cumulative dose: the weekly regimen is minimally myelotoxic, and neuropathy and other adverse events are infrequent. Weekly single-agent docetaxel may be a useful therapy in particular groups of patients such as those with reduced bone marrow reserve. It may also be a helpful means of delivering a highly active cytotoxic drug in combination with radiation therapy, other proven chemotherapy agents such as doxorubicin, and new, highly promising biological agents such as HERCEPTIN:

Phase I trial of weekly paclitaxel plus oral estramustine phosphate in patients with hormone-refractory prostate cancer

OBJECTIVES

To exploit the favorable dose intensity and safety profile of weekly paclitaxel, we conducted a Phase I trial of paclitaxel by 3-hour infusion in combination with estramustine phosphate (EM) in men with hormone-refractory prostate cancer (HRPC). The antimicrotubule drug combination of paclitaxel by 96-hour infusion plus EM is active in HRPC.

METHODS

Twenty-four patients with metastatic HRPC and progressive tumor after antiandrogen withdrawal were enrolled in this study. Oral EM was taken at a dose of 600 mg/m(2) daily for the initial 21 patients and on a reduced schedule of 280 mg twice daily for the final 3 patients. Paclitaxel was escalated from 60 to 118 mg/m(2).

RESULTS

The major toxicities were gastrointestinal and thromboembolic complications related to daily oral dosing of EM. Of the first 21 patients, one third (n = 7) discontinued therapy within 4 weeks because of protracted nausea and/or thrombotic complications. Dose-limiting toxicities at 118 mg/m(2) paclitaxel were fatigue and hepatotoxicity. Of 13 patients with measurable soft-tissue lesions, 6 had objective partial regressions, and 9 (37.5%) of 24 patients (95% confidence interval 19.1% to 59.1%) with elevated prostate-specific antigen levels had a 50% or greater decline of at least 4 weeks' duration.

CONCLUSIONS

Weekly paclitaxel at doses of 60 to 107 mg/m(2) were feasible in combination with oral EM, but daily oral EM produced unacceptable toxicity. On the basis of these results, a Phase II trial of weekly paclitaxel with the reduced dose and schedule of EM was initiated by the Eastern Cooperative Oncology Group to assess further the benefits and risks of this treatment in men with metastatic HRPC.

Weekly trastuzumab and paclitaxel therapy for metastatic breast cancer with analysis of efficacy by HER2 immunophenotype and gene amplification

PURPOSE

This phase II study evaluated weekly trastuzumab and paclitaxel therapy in women with HER2-normal and HER2-overexpressing metastatic breast cancer. Efficacy was correlated with immunohistochemical and fluorescent in situ hybridization (FISH) assay results.

PATIENTS AND METHODS

Eligible patients had bidimensionally measurable metastatic breast cancer. Up to three prior chemotherapy regimens, including prior anthracycline and taxane therapy, were allowed. Trastuzumab 4 mg/kg and paclitaxel 90 mg/m2 were administered on week 1, with trastuzumab 2 mg/kg and paclitaxel 90 mg/m2 administered on subsequent weeks. HER2 status was evaluated using four different immunohistochemical assays and FISH.

RESULTS

Patients received a median of 25 weekly infusions (range, one to 85 infusions). Median delivered paclitaxel dose-intensity was 82 mg/m2/wk (range, 52 to 90 mg/m2/wk). The intent-to-treat response rate for all 95 patients enrolled was 56.8% (95% confidence interval, 47% to 67%). A response rate of 61.4% (4.5% complete response, 56.8% partial response) was observed in 88 fully assessable patients. In patients with HER2-overexpressing tumors, overall response rates ranged from 67% to 81% compared with 41% to 46% in patients with HER2-normal expression (ranges reflect the different assay methods used to assess HER2 status). Differences in response rates between patients with HER2-overexpressing tumors and those with normal HER2 expression were statistically significant for all assay methods, with CB11 and TAB250 antibodies and FISH having the strongest significance. Therapy was generally well tolerated, although three patients had serious cardiac complications.

CONCLUSION

Weekly trastuzumab and paclitaxel therapy is active in women with metastatic breast cancer. Therapy was relatively well tolerated; however, attention to cardiac function is necessary.

Systemic treatment after sentinel lymph node biopsy in breast cancer: who, what, and why?

SLNB, although subject to numerous technical problems, has nonetheless shown great promise in predicting the status of the remaining axillary lymph nodes. The growing use of SLNB has presented the opportunity of using immunohistochemical and molecular markers to detect occult micrometastases. These micrometastases may be important for more accurate staging and prediction of patient outcomes. Current standards for the use of systemic therapy recommend multidrug chemotherapy for all but the most favorable disease (T1a/b, NO). The detection of micrometastases by SLNB in this low-risk group may change treatment recommendations to include systemic therapy. Because of the significant frequency of false-negative results in SLNB, which will depend upon the surgeon's experience, caution is urged in determining when ALND can be safely eliminated in patients with a negative SLNB.

A Phase II study of paclitaxel in patients with recurrent malignant glioma using different doses depending upon the concomitant use of anticonvulsants: a North American Brain Tumor Consortium report

BACKGROUND

The primary objective of the current study was to determine the response rate of paclitaxel in patients with recurrent malignant glioma by using different doses dependent on the concomitant use of anticonvulsants. Secondary objectives were to determine the time period to treatment failure, to evaluate toxicities, and to obtain pharmacokinetic data.

METHODS

Adult patients who had recurrent malignant glioma were treated with paclitaxel. Patients were treated at different doses depending on the concomitant use of anticonvulsants known to induce the p450 hepatic enzyme system. Patients on such agents were treated at a dose of 330 mg/m2, whereas those not on these anticonvulsants were treated at a dose of 210 mg/m2. Tumor response was assessed at 6-week intervals. Treatment was continued until documented tumor progression or unacceptable toxicity occurred, or a total of 12 paclitaxel infusions was completed.

RESULTS

From January 1997 to June 1997, 23 patients were treated with paclitaxel. Four patients were ineligible for the current study. Of the 19 eligible patients, there were no responses seen. Four (21%) had stabilization of disease. Median time to treatment failure was 1 month (95% confidence interval [CI], 1-2 mos) and median survival was 7 months (95% CI, 6-10 mos). Three patients were removed from the current study because they had toxicity. Pharmacokinetic studies demonstrated that drug levels and clearance values were consistent with previously reported findings.

CONCLUSION

Even though higher doses were administered to patients who had recurrent malignant glioma and who were on concomitant anticonvulsants, there were no objective responses to paclitaxel. Time to tumor progression was 1 month. Further testing of paclitaxel at this dose schedule does not appear to be warranted in this patient population.

Paclitaxel, estramustine phosphate, and carboplatin in patients with advanced prostate cancer

PURPOSE

To determine the safety and activity of weekly paclitaxel in combination with estramustine and carboplatin (TEC) in patients with advanced prostate cancer.

PATIENTS AND METHODS

In a dose-escalation study, patients with advanced prostate cancer were administered paclitaxel (weekly 1-hour infusions of 60 to 100 mg/m(2)), oral estramustine (10 mg/kg), and carboplatin (area under the curve, 6 mg/mL-min every 4 weeks). Paclitaxel levels were determined 0, 30, 60, 90, and 120 minutes and 18 hours after infusion, and a concentration-time curve was estimated. Once a safe dose was established, a multi-institutional phase II trial was conducted in patients with progressive androgen-independent disease.

RESULTS

Fifty-six patients with progressive androgen-independent disease were treated for a median of four cycles. The dose of paclitaxel was escalated from 60 to 100 mg/m(2) without the occurrence of DLT. Posttherapy decreases in serum prostate-specific antigen levels of 50%, 80%, and 90% were seen in 67%, 48%, and 39% (95% confidence interval, 55% to 79%, 35% to 61%, 26% to 52%) of the patients, respectively. Of the 33 patients with measurable disease, two (6%) had a complete response and 13 (39%) had a partial response. The overall median time to progression was 21 weeks, and the median survival time for all patients was 19.9 months. Major grade 3 or 4 adverse effects were thromboembolic disease (in 25% of patients), hyperglycemia (in 38%), and hypophosphatemia (in 42%). Significant leukopenia, thrombocytopenia, and peripheral neuropathy were not observed.

CONCLUSION

TEC has significant antitumor activity and is well tolerated in patients with progressive androgen-independent prostate cancer.

Phase II study of paclitaxel in patients with metastatic breast carcinoma refractory to standard chemotherapy

BACKGROUND

The authors conducted a single institution Phase II clinical trial to determine whether paclitaxel had antitumor activity in patients with metastatic breast carcinoma that was refractory to standard chemotherapy.

METHODS

Patients with metastatic breast carcinoma were eligible for the study if they had disease progression after at least 2 prior chemotherapy regimens. Patients who had received three prior regimens were treated in a separate cohort. All patients were required to have received doxorubicin in the past and were not eligible if they had received prior therapy with paclitaxel. The starting dose of paclitaxel for low risk patients was 175 mg/m2, administered as a 24-hour continuous infusion; the starting dose of paclitaxel was 150 mg/m2 for patients who had received > or = 3 prior regimens. Therapy was given every 3 weeks and continued for at least 2 courses unless there was evidence of rapidly progressing disease, for at least 3 courses if there was no change in disease and Grade 3 or 4 (based on National Cancer Institute toxicity criteria) toxicity was not noted, and for 6 courses beyond the maximum response in patients who demonstrated complete or partial responses and showed no evidence of disease progression.

RESULTS

Sixty-eight of 69 patients entered in the study were evaluable for response: 35 patients who had received 2 prior chemotherapy regimens for Stage IV disease and 33 patients who had received > or =3 prior regimens. A partial response was observed in 7 patients who had received 2 prior regimens, for an objective response rate of 20% (95% confidence interval [95% CI], 14-26%). In the group who had received > or = 3 prior regimens, a total of 6 partial responses were observed, for an objective response rate of 18% (95% CI, 12-23%). The median response duration was 8.2 months (range, 2.7-10.1 months) for the group who had received 2 prior regimens and 5.8 months (range, 2.1-9.5 months) for patients who received > or = 3 prior regimens. Responses were noted in patients with anthracycline-resistant tumors.

CONCLUSIONS

Paclitaxel was active in heavily pretreated patients with metastatic breast carcinoma, including anthracycline-resistant breast carcinoma.

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.

Phase I-II study of paclitaxel, cisplatin, and gemcitabine in advanced transitional-cell carcinoma of the urothelium. Spanish Oncology Genitourinary Group

PURPOSE

To determine the maximum-tolerated dose and the antitumor activity of a combination of paclitaxel, cisplatin, and gemcitabine in advanced transitional-cell carcinoma (TCC) of the urothelium.

PATIENTS AND METHODS

Patients with measurable, previously untreated, locally advanced or metastatic TCC and with Eastern Cooperative Oncology Group performance status < or = 2 and creatinine clearance > or = 55 mL/min were eligible. Cisplatin was given on day 1 at a fixed dose of 70 mg/m(2). Paclitaxel and gemcitabine were given on days 1 and 8 at increasing dose levels. Cycles were repeated every 21 days to a maximum of six cycles.

RESULTS

Sixty-one patients were registered. In phase I, 15 patients were entered at four different dose levels. Dose-limiting toxicity consisted of early onset (after the first cycle) grade 2 asthenia (two of six patients) and grade 3 asthenia (one of six patients) at dose level 4. A paclitaxel dose of 80 mg/m(2) and gemcitabine 1,000 mg/m(2) was recommended for phase II, and 46 additional patients were entered at this level for a total of 49 patients. Main nonhematologic toxicity was grade 2 asthenia in 18 patients, with early onset in five patients, and grade 3 in four patients. Grade 3/4 neutropenia and thrombocytopenia occurred in 27 (55%) and 11 (22%) patients, respectively. Overall, febrile neutropenia was seen in 11 patients, and one toxic death occurred because of neutropenic sepsis. The combination was active at all dose levels. In total, 58 of 61 eligible patients were assessable for response; 16 complete responses (27.6%) and 29 partial responses (50%) were observed for an overall response rate of 77.6% (95% confidence interval, 60% to 98%). The median survival time (MST) available for the phase I part of the study is 24.0 months. MST has not been reached for the whole group with the current follow-up.

CONCLUSION

This combination of paclitaxel, cisplatin, and gemcitabine is feasible and highly active in patients with advanced TCC of the urothelium. Further evaluation of this regimen in patients with TCC is warranted.

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.