Paclitaxel (Taxol) and docetaxel (Taxotere): not simply two of a kind

Treatment of ovarian cancer using intraperitoneal chemotherapy with taxanes: from laboratory bench to bedside

The combination of a taxane, paclitaxel or docetaxel, and a platinum compound has become the systemic chemotherapy of choice for primary ovarian cancer and has demonstrated high efficacy. However, ultimately most patients will die from this disease. Hence, there is a need for even more effective systemic chemotherapy or different treatment strategies. Intraperitoneal chemotherapy with taxanes is such an alternative treatment option. Ovarian cancer is theoretically an attractive malignancy for this regional treatment, because the disease remains largely confined to the peritoneal cavity. The choice of taxanes for this kind of chemotherapy is rational, because of its high activity against ovarian cancer cells and expected favourable pharmacokinetics because of limited absorption from the peritoneal cavity due to their large molecular weight and first-pass effect in the liver. In animal model and human pharmacokinetic studies, very high intraperitoneal drug concentrations and exposure and high peritoneal tumour concentrations were achieved, while systemic drug levels were low. The combination of intraperitoneal chemotherapy with hyperthermia enhances the penetration and cytotoxic activity of many drugs. Although data concerning thermal enhancement of taxane cytotoxicity are inconsistent, experimental studies show that at high locoregional concentrations there seems to be such an effect. Recently, feasibility and efficacy of this treatment have evidently been demonstrated in various clinical studies. A large randomized trial revealed improvement of outcome by intraperitoneal instillation chemotherapy with paclitaxel and cisplatin as first-line treatment. Moreover, promising results have been observed after intraoperative hyperthermic intraperitoneal chemotherapy with docetaxel for recurrent disease.

Prognostic ability of a good outcome to carpal tunnel release for decompression surgery in the lower extremity

For years, patients who were treated successfully with carpal tunnel release were told there was nothing that could be done about their lower extremity symptoms. Now that lower extremity nerve decompression has been accepted as an option to treat appropriate patients, the authors looked for correlations between a successful outcome with carpal tunnel syndrome and its predictive value of success for lower extremity nerve decompression. Data from a recent study demonstrate that a good result from upper extremity peripheral nerve surgery predicts the outcome for lower extremity peripheral nerve surgery in 88% of patients, and is, therefore, information valuable for prognosis and clinical decision-making.

Chemotherapy-induced neuropathy

Increasingly, surgeons are becoming aware of the successful treatment of symptomatic peripheral neuropathy by surgical decompression of peripheral nerves. Armed with the knowledge that patients can have underlying neuropathy with overlying anatomic compressions, surgeons have affected improvement in diabetes-induced neuropathy, neuropathy of unknown etiology, and chemotherapy-induced neuropathy. This article details the most well-known culprits in chemotherapy-induced neuropathy and discusses the putative mechanisms of action, medical management, and surgical data.

Recent developments in the systemic therapy of advanced gastroesophageal malignancies

Cancers of the upper gastrointestinal tract are a common cause of worldwide morbidity and mortality. The prognosis for patients with these cancers remains poor and only a minority of patients are cured. Systemic therapy has been used to treat patients with advanced disease but outcomes have not improved dramatically in the past few decades. Newer, more effective agents are desperately needed, and agents such as the taxanes (docetaxel and paclitaxel), irinotecan, oxaliplatin and capecitabine have recently shown some promise. In addition, molecularly targeted, non-cytotoxic therapies are being evaluated with the hope of improving the available therapeutic options. This article reviews the current clinical data regarding systemic therapy for patients with advanced upper gastrointestinal malignancies.

Transforming growth factor alpha expression drives constitutive epidermal growth factor receptor pathway activation and sensitivity to gefitinib (Iressa) in human pancreatic cancer cell lines

The epidermal growth factor receptor (EGFR) is considered an important therapeutic target in pancreatic cancer, but it is currently impossible to identify those patients who are most likely to benefit from EGFR-directed therapy. We examined the biological effects of the EGFR tyrosine kinase inhibitor gefitinib (ZD1839, Iressa) in a panel of nine human pancreatic cancer cell lines. The drug strongly inhibited DNA synthesis and induced low levels of apoptosis at clinically relevant concentrations in a subset of three of the lines (L3.6pl, BxPC3, and Cfpac1). Sensitivity to gefitinib correlated directly with ligand [transforming growth factor-alpha (TGF-alpha)] expression (r(2) = 0.71, P = 0.004) but not with surface EGFR expression. The gefitinib-sensitive cells displayed constitutive baseline EGFR phosphorylation, whereas the gefitinib-resistant cells did not. Exposure to gefitinib or a small interfering RNA construct specific for TGF-alpha reversed the constitutive EGFR phosphorylation and downstream target [extracellular signal-regulated kinases (ERK), AKT] phosphorylation in the gefitinib-sensitive cells but had no effects on ERK or AKT phosphorylation in gefitinib-resistant cells. Baseline EGFR phosphorylation was lower in a subclone of L3.6pl selected for low TGF-alpha expression, and these cells were also resistant to gefitinib-mediated growth inhibition. Gefitinib blocked the growth of tumor xenografts derived from L3.6pl cells but had no effect on the growth of tumors derived from EGFR-independent MiaPaCa-2 cells. Together, our data show that TGF-alpha expression identifies a subset of human pancreatic cancer cells that is dependent on EGFR signaling in vitro and in vivo. Quantification of TGF-alpha expression may therefore represent an effective means of identifying EGFR-responsive primary tumors.

Interstitial docetaxel (taxotere), carmustine and combined interstitial therapy: a novel treatment for experimental malignant glioma

Docetaxel (Taxotere) is a hemisynthetic, anti-cancer compound with good preclinical and clinical activity in a variety of systemic neoplasms. We tested its activity against malignant gliomas using local delivery methods. Antitumor activity was assessed in vitro against human (U87 and U80 glioma) and rat brain-tumor (9L gliosarcoma and F98 glioma) cell lines. For in vivo evaluation, we incorporated docetaxel into a biodegradable polymer matrix, determined associated toxicity in the rat brain, and measured efficacy at extending survival in a rat model of malignant glioma. Also, we examined the combined local delivery of docetaxel with carmustine (BCNU) against the experimental intracranial glioma. Rats bearing intracranial 9L gliosarcomas were treated 5 days after tumor implantation with various polymers (placebo, 5% docetaxel, 3.8% BCNU, or 5% docetaxel and 3.8% BCNU combination). Animals receiving docetaxel polymers (n=15, median survival 39.1 days) had significantly improved survival over control animals (n=12, median survival 22.5 days, P=0.01). Similarly, animals receiving BCNU polymers (n=15, median survival 39.3 days, 13.3% long-term survivors) demonstrated an increase in survival compared to the controls (P=0.04). Animals receiving the combination polymers demonstrated a modest increase in survival compared to either chemotherapeutic agent alone (n=14, median survival 54.9 days, 28.6% long-term survivors) with markedly improved survival over controls (P=0.003). We conclude that locally delivered docetaxel shows promise as a novel anti-glioma therapy and that the combination of drug regimens via biodegradable polymers may be a great therapeutic benefit to patients with malignant glioma.

Randomized phase II study comparing paclitaxel and carboplatin versus mitoxantrone in patients with hormone-refractory prostate cancer

OBJECTIVES

Mitoxantrone/prednisone was the 2002 palliative reference treatment for hormone-refractory prostate cancer (HRPC). Paclitaxel and carboplatin has demonstrated antitumor activity in HRPC. The therapeutic benefit of such treatment was compared with that of mitoxantrone.

METHODS

A randomized Phase II study was conducted that included 40 patients with HRPC who had not undergone chemotherapy. Patients in arm A received paclitaxel (175 mg/m2 every 3-week cycle) and carboplatin (area under the curve of 5 every 3-week cycle). Patients in arm B received mitoxantrone (12 mg/m2 every 3-week cycle). All the patients treated were receiving low-dose prednisone. The primary endpoint was the prostate-specific antigen response.

RESULTS

The prostate-specific antigen response to paclitaxel and carboplatin was significantly greater (40% [95% confidence interval 18.5% to 61.5%] versus 10% [95% confidence interval 1% to 32%], P = 0.031) and more durable (8.6 versus 2 months, P = 0.015) than the response to mitoxantrone. A tendency was noted for patients with measurable disease who were receiving paclitaxel and carboplatin to have a somewhat greater objective response rate than those who received mitoxantrone (23% [95% confidence interval 5.3% to 55%] versus no objective response, P = 0.060). The median overall survival was 14.5 months for the paclitaxel and carboplatin arm compared with 11.1 months for the mitoxantrone arm. The group given paclitaxel and carboplatin had significantly greater rates of sensitive neuropathy (50% versus 0%, P = 0.00026).

CONCLUSIONS

The 3-week regimen of paclitaxel and carboplatin induced a greater and more durable prostate-specific antigen response than did mitoxantrone for HRPC treatment. The major additive toxicity induced was peripheral neuropathy due to paclitaxel. Investigations with paclitaxel and carboplatin regimens merit large Phase III studies.

Autophagy is the dominant type of programmed cell death in breast cancer MCF-7 cells exposed to AGS 115 and EFDAC, new sesquiterpene analogs of paclitaxel

The molecular mechanism of cell death induced by AGS 115 and EFDAC, sesquiterpene analogs of paclitaxel, was investigated in human breast cancer MCF-7 cells. The study was carried out using laser scanning cytometry, homeostatic confocal microscopy, atomic force microscopy and electron microscopy. AGS 115 and EFDAC exhibited a microtubule-stabilizing effect as confirmed by a significant increase in alpha-tubulin aggregation. Both paclitaxel analogs also induced death in MCF-7 cells. Evaluation of biochemical and morphological features suggested that the major form of programmed cell death induced by AGS 115 and EFDAC was autophagy. This was confirmed by MAP I LC3 expression and the ultrastructural pattern revealed by electron microscopy. Surface images of cells undergoing autophagy showed that, unlike during apoptosis, the dimensions remained unchanged, but the surface of the cell was deformed. The occurrence of apoptosis was confirmed by the efflux of Smac/DIABLO from mitochondria, caspase-7 activation and DNA loss, and did not exceed 9.7%. Therefore, AGS 115 and EFDAC appear to be promising candidates for further investigation in anti-cancer therapy.

Docetaxel for treatment of solid tumours: a systematic review of clinical data

Docetaxel is a semisynthetic taxane, a class of anticancer agents that bind to beta tubulin, thereby stabilising microtubules and inducing cell-cycle arrest and apoptosis. Docetaxel was first approved for the treatment of anthracycline-refractory metastatic breast cancer in the mid-1990s. Since then, several randomised trials have reported improved time-to-progression, overall survival, or both in metastatic breast cancer treated with single-agent docetaxel or docetaxel-based combination regimens. Data from two adjuvant trials have shown a survival benefit with the addition of docetaxel to standard anthracycline-based regimens in patients with high-risk early breast cancer. In four randomised studies, docetaxel improved survival in locally advanced or metastatic non-small-cell lung cancer. Moreover, two trials have shown that docetaxel combined with estramustine or corticosteroids improves survival in metastatic androgen-independent prostate cancer. Here, we review major randomised phase III trials with docetaxel in the treatment of solid malignant disease.

Docetaxel-based chemotherapy as second-line treatment for paclitaxel-based chemotherapy-resistant hormone-refractory prostate cancer: A pilot study

OBJECTIVES

To examine docetaxel (DTX)-based chemotherapy in paclitaxel (PTX)-based chemotherapy-resistant hormone-refractory prostate cancer (HRPC) to investigate the activity and degree of toxicity in a pilot study. We have previously reported on the effectiveness of combination chemotherapy with PTX, estramustine (EMP), and carboplatin against HRPC. Although many patients with HRPC initially responded to this PTX/EMP-based combination chemotherapy, most finally progressed to PTX-resistant status within a mean of less than 1 year. DTX is an inhibitor of microtubule depolymerization like PTX and has demonstrated activity against PTX-resistant metastatic tumors.

METHODS

The subjects were 15 patients with HRPC who displayed disease progression while receiving PTX/EMP/carboplatin combination chemotherapy. The patients were treated with intravenous DTX 30 mg/m2 weekly, oral EMP 10 mg/kg daily, and intravenous carboplatin (dosed to an area under the curve of 6) on day 1 of every 4-week cycle. Treatment was continued until disease progression or excessive toxicity.

RESULTS

Each patient received a median of eight consecutive cycles. The prostate-specific antigen level decreased by 50% or more in 33.3% of patients and by 90% or more in 13.3%. The median follow-up was 49.6 weeks, with median time to progression of 25.0 weeks and median overall survival of 54.0 weeks. One patient died of interstitial pneumonitis. One patient developed secondary osteomyelodysplastic syndrome. The major severe toxicities were grade 3 or 4 anemia in 66.7% of patients, leukopenia in 26.7%, and thrombocytopenia in 40.0%.

CONCLUSIONS

The results of our study have shown that DTX is comparatively active for heavily pretreated patients with PTX-resistant HRPC. However, given the significant toxicities and small subject population, well-designed Phase I-II trials of the improved regimen are warranted.

Paclitaxel: a hope for advanced non-small cell lung cancer?

Recent studies have shown that paclitaxel (Taxol); Bristol-Myers Squibb Co., Princeton, NJ) is an active agent in the treatment of advanced non-small cell lung cancer (NSCLC). Early trials in patients with advanced NSCLC utilised a 24 h infusion schedule and reported objective tumour responses in 21 - 24% of patients. Shorter infusion schedules have equivalent efficacy, and combined results from 14 separate trials of single agent paclitaxel in advanced NSCLC show an overall tumour response rate of 26%. Alternative schedules of paclitaxel from the traditional regimen every three weeks are under active investigation, but it is premature to assess whether these will yield improved efficacy for patients with advanced NSCLC. A single multicentre randomised trial of paclitaxel versus best supportive care in advanced NSCLC showed a significant survival advantage for the chemotherapy arm. Two large randomised Phase III trials have shown that paclitaxel and cisplatin is modestly more effective than cisplatin and podophyllotoxin combinations. The addition of cisplatin or carboplatin to paclitaxel results in higher response rates than for each of the drugs as single agents, but it is unclear whether the combinations yield superior survival or quality of life compared to single agent paclitaxel, or to other paclitaxel-containing regimens.

Docetaxel (Taxotere) - an update

The development of docetaxel, a member of the taxoid family, has been recent and rapid. Phase I studies recommend that a dose of 100 mg/m(2) be administered every three weeks in a 1-h infusion. These studies have also demonstrated that the major dose-limiting toxicity is neutropenia. Major clinical research projects are now being carried out for breast cancer, non-small-cell lung cancer (NSCLC), squamous cell carcinoma of the head and neck (SCCHN) and gastric cancer. In advanced and metastatic NSCLC, Phase II studies have shown a response rate of 30 - 40%, and responses have been obtained in cis-platinum failures. In advanced and metastatic breast cancer, first-line treatment has yielded a response rate of 54 - 68%, and the rate for second-line response is only slightly lower, indicating an absence of cross-resistance. Phase II combination studies with docetaxel are in progress, and preliminary results are promising. The first Phase III study demonstrated preliminary response rates significantly higher than seen with doxorubicin, although survival data have not yet been published. Fewer results are available from SCCHN studies, but response rates have been encouraging (around 40%). Although further long-term data are needed to determine the precise role of docetaxel in combination with other drugs, it is apparent that this promising drug shows one of the best response rates for monotherapy in NSCLC and breast cancer.

Docetaxel: a new active agent in the therapy of metastatic breast cancer

Breast cancer is the most common malignancy in women, accounting for about 18% of female cancers, and over half a million new cases are diagnosed worldwide each year. Its incidence increases with age and is currently rising. Although the increased availability of screening programs has allowed earlier detection and treatment of primary breast cancers, many patients relapse with metastases after apparently successful treatment of their primary tumor and over 15,000 women in the UK and about 50,000 in the USA die from advanced disease each year. The natural course of breast cancer is very variable even after the development of metastases, and depends on a variety of tumor characteristics and prognostic factors. This is reflected in the large number of treatments currently employed. However, despite this wide choice and considerable research over the years, treatment of metastatic breast cancer (MBC) prolongs average survival times only slightly. Current therapy is aimed at achieving a balance between producing maximal tumor shrinkage to produce the most effective possible palliation of symptoms, and minimizing adverse effects. Anticancer chemotherapy is the preferred option in patients who do not respond to hormones, those with hormone-independent tumors, those with aggressive breast cancer subtypes. A variety of anticancer chemotherapy regimens, using both single and combined agents, have been shown to be effective in achieving tumor regression in MBC. Anthracyclines (doxorubicin, epirubicin) are the most active of the established monotherapies, typically producing response rates of 50-60% during initial (first-line) treatment for metastatic disease, but being effective in fewer than 25% of patients requiring second-line therapy. The drawbacks of anthracyclines include dose-limiting cumulative cardiotoxicity and the development of resistant tumor clones after the use of anthracyclines for adjuvant or first-line therapy, especially if subsequent courses are required within a year. The success of these established chemotherapeutic agents depends greatly on the number and location of metastatic sites. Lymph node and soft tissue secondaries tend to respond well, while visceral metastases (especially in the liver) carry a particularly poor prognosis despite treatment. The outlook for patients with metastases involving more than two organ systems is also bleak. Although some patients can live for years with metastatic disease, the average survival time in patients with MBC is 18-24 months, while in those with liver metastases, life expectancy averages only 6 months. High-dose anticancer chemotherapy with granulocyte-colony stimulating factor (G-CSF) or autologous bone marrow transplantation has allowed the dose intensity of anthracyclines to be increased, and has improved the response rate to about 70% in selected patients with MBC. However, this approach has not been proven to improve survival, involves the risk of greater toxicity and drug-related mortality, and patients with reduced clearance of anthracyclines due to hepatic dysfunction from liver metastases may not be suitable candidates. A number of new anticancer agents have also recently been introduced in an attempt to improve on the performance and avoid the tolerability problems associated with anthracyclines. Among these, antitubulin agents (taxoids and vinorelbine) have shown highly promising activity in MBC. This paper reviews the preclinical, phase I and phase II data for one taxoid, docetaxel. Docetaxel (Taxotere) belongs to the taxoid class of cytotoxic agents, the development of which began more than 20 years ago. In 1971, paclitaxel (Taxol) was identified as the active compound of the crude extract of the bark of the Pacific Yew tree Taxus brevifolia. However, at that time the development of paclitaxel was hampered because of the limited source of the drug and difficulties with isolation, extraction and formulation. The second active taxoid, docetaxel, was isolated by Potier et al. in 1986. Docetaxel is prepared from a non-cytotoxic precursor, extracted from the needles of the European Yew tree Taxus baccata, that is condensed with a chemically-synthesized side-chain. As the docetaxel precursor is freely available because of the regenerating capacity of the needles the development of docetaxel has thus been rapid.

Efficacy of weekly paclitaxel in patients with docetaxel-resistant metastatic breast cancer

BACKGROUND

Partial cross-resistance to paclitaxel and docetaxel has been demonstrated in pre-clinical studies.

PATIENTS AND METHODS

We retrospectively evaluated the efficacy of weekly paclitaxel 80 mg/m(2) in 82 patients with docetaxel-resisitant metastatic breast cancer. Docetaxel resistance was classified into primary resistance, defined as progressive disease while receiving docetaxel, and secondary resistance, defined as progression after achievement of a documented clinical response to docetaxel. Secondary resistance was subclassified according to the interval between the final infusion of docetaxel and the start of weekly paclitaxel into: (1) short interval, < or =120 days, and (2) long interval, >120 days.

RESULTS

The response rate of the 82 patients was 19.5% (95% confidence interval, 10.8-27.9%). The response rate according to the docetaxel resistance category was: primary resistance (n = 24), 8.3%; secondary resistance (n = 58), 24.1% (short interval [n = 39], 17.9%, and long interval, [n = 19], 36.8%). The differences in response rates among the three categories were statistically significant (p = 0.0247, Cochran-Mantel-Haenszel test). The interval between from the final docetaxel infusion and disease progression were predictors for response of weekly paclitaxel.

CONCLUSION

Weekly paclitaxel is modestly effective and safe in docetaxel-resistant metastatic breast cancer patients. However, weekly paclitaxel should not be recommended for primary resistance patients with docetaxel.

Phase II Study of Weekly Paclitaxel for Docetaxel-Resistant Metastatic Breast Cancer in Japan

The purpose of the study was to evaluate the efficacy of weekly paclitaxel (PTX) against metastatic breast cancer (MBC) that was resistant to docetaxel (DTX) given every 3 weeks. A multicenter phase II study was performed. Women with MBC resistant to DTX were eligible for enrollment. DTX resistance was defined as no tumor response to DTX and stable disease, partial response, or complete response to DTX preceding disease progression. PTX 80 mg/m(2) was administered over 1 hour once a week for 3 weeks per 4-week cycle. Among 47 enrolled patients, 46 patients were assessable for response and toxicity. The overall objective response rate (complete responses [CRs] and partial responses [PRs]) was 17.4% and overall clinical benefit rate (CRs, PRs, and stable disease >or=24 weeks) was 26.1%. The median time to progression was 11 weeks. There were a few severe hematologic toxicities related to the therapy, with grade 4 neutropenia (4.3%) and thrombocytopenia (2.2%). Grade 3 anaphylaxis and grade 3 neuropathy were observed in one patient (2.2%) each. The median delivered dose intensity was 77.6 mg/m(2)/week, 97.1% of the planned dose intensity. Weekly PTX has activity in patients with MBC resistant to DTX every 3 weeks.

Endothelial cell effects of cytotoxics: balance between desired and unwanted effects

Since Folkman defined angiogenesis more than 25 years ago as the most important process in tumour growth and metastasis, specific anti-angiogenic agents have been developed. One obvious route to block this process was until recently overlooked, however. Tumour endothelial cells are different from normal endothelial cells and may respond differently to conventional cytotoxics. Chemotherapeutic-induced vascular toxicity has been observed in various clinical studies and seems to be based on endothelial cell damage as seen in vitro in human umbilical vein endothelial cells (HUVEC) models with protracted low-dose cytostatic exposure. Translated into the clinical setting, such "metronomically" administered chemotherapy could lead to anti-angiogenesis enhancing anti-tumour efficacy of cytostatic drugs. This paper reviews the desired anti-tumour endothelial activity versus the unwanted general vascular toxicity of cytostatic drugs. Several ways to enhance the anti-tumour activity and to circumvent the unwanted vascular toxicity of these "accidental" anti-angiogenic drugs will be discussed.

Immunomodulatory effects of docetaxel on human lymphocytes

Docetaxel is an antineoplastic taxoid that interferes with microtubule polymerization dynamics and is used clinically to treat advanced cancers. Because microtubules play significant roles in T lymphocyte activation and function we characterized the in vitro immunomodulatory properties of docetaxel. Effects of docetaxel on lectin-induced peripheral blood mononuclear cell (PBMC) proliferation were measured by the 3-(4,5-dimethylthiazol-2-yl)-5-(3-carboxymethoxyphenyl)-2-(4-sulfophenyl)-2H-tetrazolium (MTS) assay and proliferating cell nuclear antigen (PCNA) staining. In addition, apoptosis was measured by annexin V staining and cell activation by determination of CD25 and CD71 cell surface expression. Intracellular calcium kinetics in lectin-activated Jurkat T lymphocytes exposed to docetaxel were investigated. Th1 cytokine production was assessed in T lymphocytes by intracellular cytokine staining. Docetaxel significantly inhibited PBMC proliferation and promoted apoptosis of lectin-activated PBMCs. Docetaxel significantly decreased expression of CD71 but not that of CD25. Docetaxel altered intracellular calcium homeostasis but did not affect Th1 cytokine production in T lymphocytes. In conclusion we demonstrate that docetaxel, although exerting significant antiproliferative effects on lymphocytes and promoting activation-induced apoptosis does affect only partially lymphocyte activation and function and does not affect Th1 cytokine production. These results suggest maintenance of lymphocyte functions important for host tumor surveillance and suggest that this compound may have a role in the treatment of cancer arising organ transplant recipients.

Inhibition of tumor-associated fatty acid synthase hyperactivity induces synergistic chemosensitization of HER -2/ neu -overexpressing human breast cancer cells to docetaxel (taxotere)

The lipogenic enzyme fatty acid synthase (FAS) is differentially overexpressed and hyperactivated in a biologically aggressive subset of breast carcinomas and minimally in most normal adult tissues, rendering it an interesting target for antineoplastic therapy development. Recently, a molecular connection between the HER -2/ neu (c- erb B-2) oncogene and FAS has been described in human breast cancer cells. Here, we examined the relationship between breast cancer-associated FAS hyperactivity and HER -2/ neu -induced breast cancer chemoresistance to taxanes. Co-administration of docetaxel (Taxotere) and the mycotoxin cerulenin, a potent and non-competitive inhibitor of FAS activity, demonstrated strong synergism in HER -2/ neu -overexpressing and docetaxel-resistant SK-Br3 cells, modest synergism in moderately HER -2/ neu -expressing MCF-7 cells, and it showed additive effects in low HER -2/ neu -expressing and docetaxel-sensitive MDA-MB-231 cells. Sequential exposure to cerulenin followed by docetaxel again yielded strong synergism in SK-Br3 cells, whereas antagonistic and moderate synergistic interactions were observed in MCF-7 and MDA-MB-231 cells, respectively. Importantly, inhibition of FAS activity dramatically decreased the expression of HER -2/ neu oncogene in SK-Br3 breast cancer cells. To the best of our knowledge this is the first study demonstrating that FAS is playing an active role in HER -2/ neu -induced breast cancer chemotherapy resistance.

Antitumour and antiangiogenic effects of IDN 5390, a novel C-seco taxane, in a paclitaxel-resistant human ovarian tumour xenograft

IDN 5390 is a novel C-seco taxane analogue selected for preclinical development on the basis of its antimotility activity on endothelial cells, antitumour efficacy in a large panel of human tumour xenografts and high tolerability in mouse. On the basis of oral availability, IDN 5390 is suitable for protracted administration schedules. Such a treatment schedule has been reported as the most appropriate to exploit the antiangiogenic effects of cytotoxic drugs. An ability to downregulate angiogenesis-related growth factors in tumour cells has been described for IDN 5390. The aim of the study was to investigate the antitumour and antiangiogenic potential of oral IDN 5390 on a human ovarian carcinoma xenograft, the INT.ACP/PTX, resistant to paclitaxel (PTX). Such tumour line was derived in vivo from a cisplatin-resistant tumour line, the A2780/DDP, which is sensitive to PTX. Compared to the parental cells, INT.ACP/PTX cells exhibited a high level of Pgp expression, resulting in a reduced in vitro sensitivity to both PTX and IDN 5390. The INT.ACP/PTX tumour xenograft was still resistant to PTX, but responsive to IDN 5390, when delivered per os, by a daily prolonged schedule. A direct effect on tumour cells, allowed by the high tolerability of the compound in mouse, cannot be excluded in vivo. Immunohistochemical analysis indicated a significant reduction of microvessel density in IDN 5390-treated tumours, lasting till 7 days after the last drug administration. Thus, a prolonged inhibitory effect on tumour angiogenesis is consistent with the persistent growth control of INT.ACP/PTX tumour achieved by IDN 5390. On the contrary, the low tolerability and the limited oral availability of conventional taxanes do not allow an easy feasibility of such treatment regimen. Thus, the tolerability profile of IDN 5390 in preclinical systems and its efficacy in PTX-resistant tumours support the therapeutic interest for its clinical development, with particular attention to oral daily prolonged schedules.

Cyclooxygenase-2: a potential target in breast cancer

Use of nonsteroidal anti-inflammatory drugs has been shown to result in a 40% to 50% reduction in the relative risk of developing colorectal cancer. Cyclooxygenase-2 (COX-2) overexpression occurs in 43% of human invasive breast cancers and 63% of ductal carcinomas in situ. There is considerable in vitro, animal model, and epidemiologic evidence to suggest that COX-2 may play some role in breast tumor initiation and progression. PGE(2) is a major downstream mediator of COX-2 that promotes cellular proliferation and angiogenesis, makes cells resistant to apoptosis, enhances invasiveness, and modulates immunosuppression. COX-2 and COX-2-derived PGE(2) may be involved in mammary carcinogenesis. Therefore, COX-2 selective inhibitors may have a role in breast cancer prevention.

Basic treatment considerations: chemotherapy

Lung cancer represents a major global health problem, with more than a million deaths reported each year. Because there are no effective screening tools to date, diagnosis of the disease at an advanced stage is a common feature. Over the past 20 years, elegant strides have been made in the treatment of patients with advanced NSCLC. Several novel chemotherapy agents that are efficacious and possess favorable toxicity profiles have been developed recently. In addition to evaluating novel combinations, alternative schedules to improve toxicity profiles are subjects of clinical trials. Much work needs to be done, however, to improve the outcome for patients with lung cancer. Chemotherapy extends life and improves quality of life for patients with stage IIIB/IV NSCLC. Combined modality therapy with radiation and chemotherapy improves the outcome for patients with locally advanced NSCLC and is associated with a curative potential. Molecularly targeted therapies are under rigorous evaluation, although the initial results have been disappointing. In the upcoming years, we will learn effective means to incorporate molecularly targeted therapies to existing treatment paradigms in lung cancer.

Docetaxel Combined With Trastuzumab Is an Active Regimen in HER-2 3+ Overexpressing and Fluorescent In Situ Hybridization–Positive Metastatic Breast Cancer: A Multi-Institutional Phase II Trial

Purpose

To determine the efficacy and safety of weekly docetaxel and trastuzumab as first- or second-line therapy in women with HER-2–overexpressing metastatic breast cancer and to correlate the efficacy of trastuzumab with HER-2 status as determined by immunohistochemistry assay and fluorescent in situ hybridization (FISH).

Patients and Methods

Twenty-six women with HER-2–positive (HercepTest [Dako Corp, Carpenteria, CA]2 to 3+) metastatic breast cancer were enrolled onto this study of trastuzumab (4 mg/kg load; 2 mg/kg/wk administered intravenously) and docetaxel (35 mg/m2/wk for 6 weeks).

Results

Using an intent-to-treat analysis, the overall response rate was 50% (13 of 26 patients). Eight patients (31%) had a period of stable disease posttherapy. Among HER-2 3+ patients, the overall response rate was 63% (12 of 19 patients) compared with a 14% response rate (one of seven patients) for HER-2 2+ patients (P = .07). Patients with FISH-positive tumors experienced an overall response rate of 64%. Median time to progression was 12.4 months for the entire cohort (HER-2 3+ tumors, 12.3 months; HER-2 2+ lesions, 9.5 months) and median survival was 22.1 months. All HER-2 3+ patients were FISH-positive; the only HER-2 2+ patient responding to treatment was also FISH-positive. Grade 4 toxicities occurred in four patients; most toxicities were mild.

Conclusion

Trastuzumab plus docetaxel is an active and well-tolerated regimen in women with HER-2 3+ overexpressing or FISH-positive metastatic breast cancer.

Pharmacological effects of formulation vehicles : implications for cancer chemotherapy

The non-ionic surfactants Cremophor EL (CrEL; polyoxyethyleneglycerol triricinoleate 35) and polysorbate 80 (Tween) 80; polyoxyethylene-sorbitan-20-monooleate) are widely used as drug formulation vehicles, including for the taxane anticancer agents paclitaxel and docetaxel. A wealth of recent experimental data has indicated that both solubilisers are biologically and pharmacologically active compounds, and their use as drug formulation vehicles has been implicated in clinically important adverse effects, including acute hypersensitivity reactions and peripheral neuropathy.CrEL and Tween 80 have also been demonstrated to influence the disposition of solubilised drugs that are administered intravenously. The overall resulting effect is a highly increased systemic drug exposure and a simultaneously decreased clearance, leading to alteration in the pharmacodynamic characteristics of the solubilised drug. Kinetic experiments revealed that this effect is primarily caused by reduced cellular uptake of the drug from large spherical micellar-like structures with a highly hydrophobic interior, which act as the principal carrier of circulating drug. Within the central blood compartment, this results in a profound alteration of drug accumulation in erythrocytes, thereby reducing the free drug fraction available for cellular partitioning and influencing drug distribution as well as elimination routes. The existence of CrEL and Tween 80 in blood as large polar micelles has also raised additional complexities in the case of combination chemotherapy regimens with taxanes, such that the disposition of several coadministered drugs, including anthracyclines and epipodophyllotoxins, is significantly altered. In contrast to the enhancing effects of Tween 80, addition of CrEL to the formulation of oral drug preparations seems to result in significantly diminished drug uptake and reduced circulating concentrations. The drawbacks presented by the presence of CrEL or Tween 80 in drug formulations have instigated extensive research to develop alternative delivery forms. Currently, several strategies are in progress to develop Tween 80- and CrEL-free formulations of docetaxel and paclitaxel, which are based on pharmaceutical (e.g. albumin nanoparticles, emulsions and liposomes), chemical (e.g. polyglutamates, analogues and prodrugs), or biological (e.g. oral drug administration) strategies. These continued investigations should eventually lead to more rational and selective chemotherapeutic treatment.

The immunopharmacology of paclitaxel (Taxol®), docetaxel (Taxotere®), and related agents

Paclitaxel (Taxol) and docetaxel (Taxotere) are among the most unique, and successful, chemotherapeutic agents used for the treatment of breast and ovarian cancer. Both agents have anti-mitotic properties derived from binding to tubulin and excessive stabilization of microtubules. Their anti-neoplastic effects derive from this mechanism. Distinct from their effects on microtubule stabilization, paclitaxel, docetaxel, and related taxanes display immunopharmacological traits. In this review, we discuss their induction of pro-inflammatory genes and proteins; the current hypotheses on the molecular mechanism for this induction, especially its relationship to the lipopolysaccharide (LPS) signaling pathway. We also discuss the structure-activity relationships (SAR) that govern gene induction, especially the striking differences between the SAR for murine and human cells in vitro. Lastly, we discuss the immunopharmacological traits of paclitaxel and docetaxel in terms of their relevance to human clinical pharmacology and toxicology and their activity in animal models of autoimmune disorders.

Long-term suppression of lymphangitic lung metastasis from breast cancer using biweekly docetaxel: a case report

A 45-year-old woman underwent a modified radical mastectomy for right breast cancer in July 1996. As lymph node metastases were quite advanced, chemotherapy was started with anthracyclines. Four years after surgery, cough and dyspnea appeared. Chest radiograph and CT showed reticular shadows bilaterally and slight pleural effusion, suggesting lymphangitic lung metastasis of breast cancer. Biweekly intravenous docetaxel (TXT,45 mg/m2) was initiated. Four courses of TXT ameliorated her complaints and radiographic findings. A total of 30 continuous courses of TXT suppressed disease exacerbation for 18 months until new lesions manifested in January 2002. The main side effects were grade 2 leukopenia and alopecia. This case report describes a patient with long-term suppression of lymphangitic lung metastasis of breast cancer using biweekly TXT without severe side effects or worsening quality of life.

Intraperitoneal taxanes

The taxanes appear to be promising agents for intraperitoneal use. Paclitaxel is currently undergoing Phase III investigation for the treatment of ovarian cancer. Docetaxel requires further Phase II study, but its impressive activity with systemic administration may be optimized with intraperitoneal administration for the treatment of peritoneal surface malignancy.

Effect of the combination of docetaxel, zoledronic acid, and a COX-2 inhibitor on the growth of human breast cancer cell lines

Current trends in the treatment of human tumors are with drug combinations that result in improved responses as well as the ability to use less toxic concentrations of the drugs. Recent reports have shown that COX-2 inhibitors and taxanes are effective in the suppression of human tumor growth. The bisphosphonate, zoledronic acid, primarily used in the treatment of bone metastases, also inhibits proliferation and induces apoptosis in human breast and prostate carcinoma and multiple myeloma. HER-2/neu overexpression has been suggested as a mechanism for resistance to both hormonal therapy as well as chemotherapy. This study examines the effects of combining a cyclooxygenase-2 inhibitor with zoledronic acid and/or docetaxel in a HER-2/neu transfected and control human breast cancer cell line. All three compounds produced dose-dependent growth inhibition in both cell lines. The HER-2/neu transfected MCF/18 cells, however, were less sensitive to zoledronic acid than the control MCF/neo cells, 9% to 53% inhibition and 18% to 67%, respectively. Enhanced growth inhibition was observed in both cell lines with the combination of docetaxel and SC236 and the combination of docetaxel and zoledronic acid. The combination of SC236 with zoledronic acid also gave an enhanced inhibitory effect in the MCF/neo line. This combination, however, was additive in the HER-2/neu transfected MCF/18 cell line. The triple combination of SC236, zoledronic acid and/or docetaxel resulted in a small increase in growth inhibition compared to that seen with the double combinations.

Emerging role of taxanes in adjuvant and neoadjuvant therapy for breast cancer: the potential and the questions

Adjuvant chemotherapy has gained increasing prominence in the treatment of nonmetastatic breast cancer, producing gradual improvement in the survival of these patients. The taxanes offer great hope for adding to the progress in adjuvant treatment, but data have been conflicting. Early results of multi-center trials testing the sequential addition of paclitaxel to anthracycline-based adjuvant chemotherapy have perhaps been prematurely reported, but have already made a major impact on patterns of care for node-positive and even some node-negative patients. The early dramatic improvements in CALG 9344 are fading with time, however, and have not been confirmed by a second similar trial, NSABP B-28. Moreover, it cannot be stated with certainty whether the modest improvements observed by sequential addition of paclitaxel reflect the ability of this drug to kill anthracycline-resistant cancer cells or the increased total duration and amount of treatment. By contrast, the early results of the BCIRG 001 trial suggest that combining docetaxel with doxorubicin may significantly increase survival, but these early results should be viewed with caution and do not necessarily mean that docetaxel is superior to paclitaxel. The role of neoadjuvant chemotherapy for breast cancer has also expanded over the past 2 decades, from its initial use for inoperable locally advanced breast cancer (LABC) to its current use for patients with large operable tumors to make BCT feasible. The neoadjuvant approach also has an important role in clinical trials, where it will allow more rapid comparison of treatment regimens than can be accomplished in the adjuvant setting and provides an opportunity to analyze biologic markers as predictors of response. The value of this approach, however, will ultimately depend on a clear demonstration, not yet available, that a change in therapy that increases primary tumor response will also lead to improved long-term survival. The roles of docetaxel and paclitaxel in the neoadjuvant setting has been actively investigated over the past 5 to 10 years, and exciting results are beginning to emerge. Clearly, docetaxel has potent antitumor activity against breast cancer. Several preliminary results suggest that addition of docetaxel to an anthracycline-based regimen, particularly when added sequentially, as in NASBP B-27 and the Aberdeen trial, results in higher clinical and pathologic response rates. Whether this will translate into increased long-term survival, as suggested by the early results of the Aberdeen trial, remains to be seen. Whether sequential addition of docetaxel to doxorubicin is more or less effective than combining these drugs also has not been established. The results from M.D. Anderson suggesting that paclitaxel given on a weekly schedule was more effective than the same drug given every 3 weeks are particularly intriguing, and they may help to explain why the adjuvant studies with paclitaxel given every 3 weeks have not produced more dramatic results, whereas several studies with docetaxel (also given every 3 weeks) seem so positive. It may be that paclitaxel, with activity that is highly schedule-dependent and for which cell killing is more dependent on the duration of exposure, works best when given weekly, whereas the efficacy of docetaxel depends less on scheduling. If this is the case, then weekly paclitaxel may turn out to be equally effective as docetaxel appears to be even when given every 3 weeks. Alternatively, if docetaxel is simply a more active drug, then giving docetaxel weekly may be the most effective taxane regimen. Whether routine use of weekly chemotherapy administration in the adjuvant or neoadjuvant setting is practical or not is largely subjective, but at least it appears that the toxicity of this approach is acceptable. These issues are also being addressed in ongoing trials. Finally, taxanes have produced dramatic increases in response rates in the neoadjuvant setting, but, except for the Aberdeen trial, survival benefits have not yet been shown. If, however, the high pCR rates do translate into overall survival benefits that are greater than adding taxanes to postoperative adjuvant therapy, it might suggest that, unlike other drugs, taxanes are actually more effective before surgery than after, as predicted originally based on laboratory experiments. Clearly, much work remains to be done in this area of research on breast cancer therapy.

Bcl-2 down-regulation is a novel mechanism of paclitaxel resistance

Taxanes act by inhibiting microtubule dynamics; in this study, we have investigated mitochondria as an additional target of taxanes. We incubated isolated mitochondria in the presence of taxanes with or without stimulation of the mitochondrial respiratory state. Results showed that they rapidly induced the loss of deltapsim after stimulation of the respiratory state. To evaluate the binding of [14C]paclitaxel to isolated mitochondria, mitochondrial proteins were precipitated yielding 18.6 +/- 2.1 cpm/microg of protein. After stimulation of the respiratory state, binding of [14C]paclitaxel increased up to 163.2 +/- 46.7 cpm/microg of protein. CPM values after Bcl-2 immunoprecipitation was 62.8-fold higher than those of the control antibody, thereby indicating the involvement of Bcl-2 in paclitaxel binding. Then, we established a panel of A2780 cell lines resistant to increasing doses of paclitaxel alone or to high doses of paclitaxel/cyclosporin A (A2780 TC cells). In both cases, Bcl-2 expression was consistently down-regulated, whereas levels of other members of the Bcl-2 family, such as Bax and Bcl-x, did not change in paclitaxel-resistant cell lines. When A2780TC cells were stably transfected with a Bcl-2 construct, paclitaxel sensitivity was partially restored, thereby supporting a direct role of Bcl-2 down-regulation in the maintenance of drug-resistance. Finally, we examined Bcl-2 by immunohistochemistry in a small subset of ovarian cancer paclitaxel-resistant patients and we noticed that the protein is down-regulated in this clinical setting with respect to the expression levels found in drug-sensitive tumors. These findings demonstrate that Bcl-2 is an additional intracellular target of taxanes and that its down-regulation is involved in taxane resistance.

Thermal enhancement of new chemotherapeutic agents at moderate hyperthermia

BACKGROUND

Hyperthermia enhances the cytotoxicity of some chemotherapeutic agents. We have studied the effect of moderate hyperthermia (41.5 degrees C) on the cytotoxicity of five new chemotherapeutic agents (docetaxel, paclitaxel, irinotecan, oxaliplatin, and gemcitabine) and melphalan against a spontaneous murine fibrosarcoma.

METHODS

The tumor was an early-generation isotransplant of a spontaneous C3Hf/Sed mouse fibrosarcoma, FSa-II. Hyperthermia was administered by immersing the tumor-bearing foot into a constant temperature water bath set at 41.5 degrees C for 30 minutes when the tumor reached 34 mm(3). Chemotherapy was administered intraperitoneally immediately before hyperthermia. Tumor response was studied by the mean tumor growth time and the mean tumor growth delay time.

RESULTS

Hyperthermia significantly increased the tumor growth times of the animals treated with docetaxel, irinotecan, and gemcitabine at low dose and these drugs plus oxaliplatin at high dose. Docetaxel at high dose showed the greatest control of tumor growth by hyperthermia, with a 26% reduction. Concerning the taxanes, paclitaxel cytotoxicity was not enhanced by hyperthermia, but docetaxel was enhanced by hyperthermia at both doses of drug.

CONCLUSIONS

Moderate hyperthermia increases the cytotoxicity of docetaxel, irinotecan, and gemcitabine on mouse fibrosarcoma. Paclitaxel did not show heat enhancement. Oxaliplatin and docetaxel showed greater heat enhancement when the drug dose was high.

Curative treatment of gastric cancer: towards a multidisciplinary approach?

Despite marked decreases in incidence over the last century, particularly in developed countries, gastric cancer is still the second-most common tumor worldwide. Surgery remains the gold standard for the cure of locoregional disease. However, in most countries, the diagnosis is made at an advanced stage, and the 5-year survival for surgically resectable disease stays far below 50%. The efficacy of chemotherapy and/or radiation therapy in addition to surgery has been actively studied over the last 30 years. Unfortunately, with few exceptions, most studies of adjuvant therapy in gastric cancer have given deceiving results. The purpose of this review is to address the reasons for our failure to objectivate an improvement in the cure of gastric cancer with adjuvant treatment in most trials, and to consider potential solutions. The low efficacy of chemotherapy regimens available up to now may have hampered our progress. In addition, many previous studies suffered limitations of design or methodology (e.g. low accrual, inadequate disease stage selection, inadequate surgical treatment) that may have obscured a treatment effect. Furthermore, the reduced treatment tolerance of post-gastrectomy patients, perhaps due to their poor nutritional status, results in decreased or delayed adjuvant systemic therapy, with potential adverse consequences in its efficacy. Among potential solutions, the arrival of new drugs, taxanes and topoisomerase I inhibitors in particular, which have shown encouraging results in metastatic disease, may increase the impact of chemotherapy in a multidisciplinary treatment approach. Pre-treatment with chemotherapy and/or radiation therapy prior to surgery may also be advantageous, averting the problems associated with post-surgical treatment. Such an approach has been shown to be feasible in phase II studies, and is relatively well tolerated by patients. Several carefully designed randomized phase III trials are underway to answer this question.

Nonlinear accumulation in the brain of the new taxoid TXD258 following saturation of P-glycoprotein at the blood-brain barrier in mice and rats

1. TXD258, a new taxoid antitumor agent, is a poor substrate for the P-glycoprotein (P-gp) in Caco-2 cells. In this study, we investigated the amount of drug accumulating in the brains of rats and mice under a variety of conditions (dose and infusion time, species and plasma concentration) using conventional in vivo pharmacokinetic techniques and in situ brain perfusion. 2. Mice were infused with radiolabeled TXD258 at 15, 30, 45 and 90 mg m(-2) for 45 s or 1 h and rats were infused with 15 and 60 mg m(-2) over 2.3 min. The radioactivity in the plasma and brains was measured. The brain concentrations of TXD258 in mice and rats were maximal from 2 min to 1 h postinfusion and radioactivity was still detectable at 168 h. While the plasma concentration of TXD258 increased linearly in mice with the infused dose, the brain content increased more than proportionally with the dose between 15 and 90 mg m(-2). This nonlinear uptake of TXD258 also occurred in the plasma and brain of the rat. 3. These findings suggest that the protein-mediated efflux across the blood-brain barrier (BBB) becomes saturated. In situ brain perfusion studies confirmed that TXD258 is a P-gp substrate at the BBB of mice and rats. The P-gp of both species was saturated at the half-inhibitory concentration ( approximately 13 micro M) produced by i.v. infusion. 4 Thus, the observed nonlinear accumulation of TXD258 in the brain seems to occur by saturation of the P-gp at the rodent BBB. This saturation could have several advantages, such as overcoming a P-gp-mediated efflux, but the nonlinear pharmacokinetics could increase the risk of toxicity.

Comparison of antiangiogenic activities using paclitaxel (taxol) and docetaxel (taxotere)

Tumor growth requires a competent vascular supply and angiogenesis has been considered as a potential target for the treatment of several cancers. The two clinically approved taxanes, paclitaxel and docetaxel, are novel antimitotic agents that are under extensive investigation in clinical trials. Both taxanes have demonstrated significant activity against many solid tumors, but little is known about the effect of paclitaxel and docetaxel on endothelial cell function and angiogenic processes. The purpose of our study was to examine and compare the effects of these drugs on angiogenic processes in vitro and in vivo. These processes include: proliferation, migration and differentiation of cultured human umbilical vein endothelial cells (HUVEC) (in vitro), capillary sprouting of rat aortic ring explants (ex vivo) and HT1080 tumor growth in vivo. Our results demonstrate that endothelial cells are 10-100-fold more sensitive to these drugs than tumor cells. Additionally, comparison of the taxanes demonstrated that angiogenesis is blocked by both drugs primarily via inhibition of proliferation and differentiation (tube assay) and induction of cell death. Docetaxel, however, appears to be more potent at inhibiting angiogenesis, with an IC(50) concentration 10x less than that of paclitaxel. We conclude that these important findings should be taken in account in clinical trials where tumor angiogenesis is being targeted.

Decreased response to paclitaxel versus docetaxel in HER-2/neu transfected human breast cancer cells

Taxanes are effective in the treatment of metastatic breast cancer. Docetaxel has been shown to be more potent than paclitaxel in inducing bcl-2 phosphorylation and apoptosis and is clinically active in some paclitaxel-resistant breast tumors. HER-2/neu overexpression has been shown to correlate with resistance to hormonal therapy as well as chemotherapy. Using a HER-2/neu transfected MCF-7 human breast cancer cell line, we investigated the role of HER-2/neu overexpression on resistance to paclitaxel and docetaxel treatment. A control vector transfected MCF-7 human breast cancer cell line (MCF/neo) and a HER-2/neu transfected MCF-7 line (MCF/18) were treated with various concentrations of docetaxel or paclitaxel. Cell number was assessed using the MTT tetrazolium dye assay. In the control vector transfected MCF/neo cell line, paclitaxel and docetaxel gave similar dose-dependent growth inhibition ( p = 0.175). In HER-2/neu transfected MCF/18 cells, docetaxel treatment resulted in a dose-dependent inhibition similar to that seen in MCF/neo cells. Paclitaxel, however, gave significantly less growth inhibition than docetaxel in the HER-2/neu overexpressing MCF/18 cells (p = 0.0003). These data suggest that HER-2/neu overexpression may contribute to paclitaxel resistance. In contrast, the cytotoxic effects of docetaxel in these breast carcinoma cells are not affected by HER-2/neu expression. Therefore, docetaxel may be the preferred taxane therapy in HER-2/neu overexpressing breast tumors.

Pharmacokinetic study of docetaxel in intraoperative hyperthermic i.p. chemotherapy for ovarian cancer

The purpose of this study was to evaluate the pharmacokinetics and toxicity of docetaxel in continuous hyperthermic perfusion peritoneal chemotherapy (CHPPC) after cytoreductive surgery for peritoneal involvement of gynecological malignancies, mainly ovarian cancer. Eighteen patients, with a mean age of 64 years (range 51-80), underwent cytoreductive surgery and subsequent CHPPC with 75 mg/m2 docetaxel at 41-43 degrees C. One patient was treated twice. In eight cases, peritoneal fluid and blood samples were obtained for pharmacokinetic analysis. Death occurred in two heavily pretreated elderly patients with a high volume i.p. tumor recurrence, probably reflecting poor patient selection (mortality rate 10.5%). Other complications, mainly minor, were recorded after 63% of the procedures. Hematological docetaxel-induced toxicity was limited, while the incidence of wound complications was relatively high and probably caused by the direct exposure of the wound to docetaxel during CHPPC. The maximal i.p. versus plasma concentration ratio ranged from 17 to 95 (average 45), while the i.p. versus systemic exposure ratio varied between 105 and 555 (average 207). We conclude that the use of docetaxel in CHPPC following cytoreductive surgery seems feasible and results in a high i.p. versus systemic exposure ratio. The AUC for the peritoneal cavity is on average 13-27 times higher after i.p. administration of 75 mg/m2 during CHPPC than the AUC achieved in the systemic compartment after i.v. administration of the recommended dose of 100 mg/m2, while docetaxel-induced systemic toxicity is highly limited.

Taxane-induced nail changes: incidence, clinical presentation and outcome

The clinical characteristics of nail changes in seven patients receiving taxane-containing chemotherapy are described. They include nail pigmentation, subungual hematoma, Beau's lines and onycholysis and subungual suppuration. The incidence of such changes (ranging from 0% to 44%) is reviewed from a Medline search of the literature.

Taxanes for advanced non-small cell lung cancer

The emergence of novel chemotherapeutic agents with promising anticancer activity in non-small cell lung cancer (NSCLC) during the 1990s has led to an expanded role for chemotherapy in the management of this disease. The taxanes (paclitaxel and docetaxel) are novel microtubule stabilising agents, and have become an integral part of several commonly-used chemotherapy regimens in NSCLC. Taxanes inhibit the growth of lung cancer cell lines, exhibit synergistic interaction with other chemotherapy agents and enhance the efficacy of radiation in vitro. When used in low doses (metronomic dosing), they have important antiangiogenic properties. Several Phase II and III clinical trials have established the efficacy of the taxanes, as single agents and when used in combination with a platinum compound, in the treatment of advanced NSCLC. The use of a taxane in combination with a platinum compound has become an acceptable standard for patients with advanced or metastatic NSCLC. In addition to its efficacy in the first-line therapy of NSCLC, docetaxel is also the FDA-approved second-line agent for recurrent or relapsed NSCLC in the US. Several ongoing trials are comparing the efficacy of combining molecularly targeted agents with taxane-based regimens for the treatment of advanced NSCLC.

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.

Combination of taxanes and anthracyclines in first-line chemotherapy of metastatic breast cancer: an interim report

Anthracyclines and taxanes are among the most effective agents in the treatment of advanced breast cancer, refractory or non-responsive to endocrine manipulation. Several recently published phase III studies have addressed the role of these compounds in combination compared with established chemotherapy regimens. This report considering a total of 4244 patients evaluates the data of those trials with respect to the efficacy and toxicity of the treatment regimens. Currently, evidence is growing that especially patients with symptomatic visceral tumour spread may benefit from the combined application of anthracyclines and taxanes. Adequately dosed polychemotherapy appears to be more successful than monotherapy, and, at present, the combination of anthracyclines (doxorubicin, epirubicin) and taxanes (docetaxel (Doc), paclitaxel (Pac)) might lead to a promising approach to improve the course of the metastatic disease.

A phase II study of dose-dense docetaxel and mitoxantrone in the treatment of patients with high-risk metastatic breast cancer

Doxetaxel (DCT) and mitoxantrone (MX) are highly active and potentially synergistic agents in the treatment of metastatic breast cancer (MBC). This pilot study evaluates the combination of dose-dense DCT and MX in patients with MBC to determine the efficacy and toxicity of this therapy. Thirty-six patients (56.1+/-1.7 years) were studied. The patients received DCT (35 mg/m(2) q1w) and MX (6 mg/m(2) q2w) for 6 weeks of an 8-week interval. Patients with tumor response or stable disease (SD) continued the treatment for a maximum of two additional periods. Hematologic and non-hematologic parameters were determined using the WHO common toxicity score. During this study 14 patients (40%) experienced partial response, 14 (40%) SD. In 20% of the cases the disease progressed on therapy. The treatment with DCT and MX was well tolerated. Seventeen patients (47%) experienced grade 3 leukopenia. Other hematologic and non-hematologic side effects did not exceed grade 2. One patient died during therapy because of a pulmonary embolism, which was unlikely related to active agents. Dose-dense DCT and MX combines both clinical activity and convenience for the patient. Therefore, we conclude that this regimen is a promising therapy in MBC, which warrants confirmation by large-scale clinical trials.

Implementation and results of a test dose program with taxanes

PURPOSE

A pilot taxane test-dose policy was developed and implemented to determine whether the severity of patient hypersensitivity reaction and drug waste would be reduced.

PATIENTS AND METHODS

Data from 206 eligible cancer patients undergoing first-dose taxane chemotherapy were analyzed. The severity of hypersensitivity reactions before and after the implementation of taxane test dose was graded (scale 1-4) and analyzed for statistical differences between groups. Average drug wastage was calculated before and after program initiation.

RESULTS

Twenty-two of 206 patients (10.7%) experienced a hypersensitivity reaction. The mean hypersensitivity reaction severity for reacting patients who did not receive a test dose (N = 12) was 3.3, and for those who were given a test dose (N = 10), it was 1.5. Only one of five patients who experienced a hypersensitivity reaction that required hospitalization was from the test-dose group. The value of drug alone wasted before test-dose utilization was about $1794 per reacting patient, and the use of taxane test doses saved approximately $1784 per reacting individual. This represented more than a $178 savings for every patient receiving a taxane for the first time. These figures do not include resuscitation, hospital, and other subsequent other costs associated with morbidity.

CONCLUSIONS

Implementation of a taxane test-dose policy significantly reduced hypersensitivity reaction severity, drug wastage, and hospitalizations.