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BACKGROUND: Skeletal metastases often occur in men with castration-resistant prostate cancer (CRPC) where bone biomarkers are prognostic for overall survival (OS). In those with highly elevated markers, there is preferential benefit from bone-targeted therapy. In the phase IIIS0421 docetaxel +/- atrasentan trial, clinical covariates and bone biomarkers were analyzed to identify CRPC subsets with differential outcomes. SUBJECTS AND METHODS: Markers of bone resorption [N-telopeptide-NTx; pyridinoline-PYD] and formation [C-terminal collagen propeptide-CICP; bone alkaline phosphatase-BAP] were measured in pre-treatment sera. Bone biomarkers and clinical covariates were included in a Cox model for OS; bone markers were added in a stepwise selection process. Receiver operating characteristic (ROC) curves were constructed for risk factor models +/- bone markers. Significant variables were allowed to compete in a classification and regression tree (CART) analysis. Hazard ratios(HR) were calculated by comparing OS in each of the terminal nodes to a reference group in a Cox model. RESULTS: 750 patients were included. Each bone marker significantly contributed to the risk factor-adjusted OS Cox model, with higher levels associated with worse OS. BAP (HRâ¯=â¯1.15, pâ¯=â¯0.008), CICP (HRâ¯=â¯1.27, pâ¯<â¯0.001), and PYD (HRâ¯=â¯1.21, pâ¯=â¯0.047) in combination were significantly associated with OS. Prognostic accuracy was improved by addition of bone markers to clinical covariates. CART analysis selected CICP, BAP, hemoglobin, and pain score for the final OS model, identifying five prognostic groups. CONCLUSIONS: Elevated serum bone biomarker levels are associated with worse OS in bone-metastatic CRPC. Bone biomarkers can identify unique prognostic subgroups. These results further define the role of bone biomarkers in the design of CRPC trials.
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Background: Activation of the phosphoinisitide-3 kinase (PI3K) pathway through mutation and constitutive upregulation has been described in renal cell carcinoma (RCC), making it an attractive target for therapeutic intervention. We performed a randomized phase II study in vascular endothelial growth factor (VEGF) therapy refractory patients to determine whether MK-2206, an allosteric inhibitor of AKT, was more efficacious than the mammalian target of rapamycin inhibitor everolimus. Patients and methods: A total of 43 patients were randomized in a 2:1 distribution, with 29 patients assigned to the MK-2206 arm and 14 to the everolimus arm. Progression-free survival (PFS) was the primary endpoint. Results: The trial was closed at the first futility analysis with an observed PFS of 3.68 months in the MK-2206 arm and 5.98 months in the everolimus arm. Dichotomous response rate profiles were seen in the MK-2206 arm with one complete response and three partial responses in the MK-2206 arm versus none in the everolimus arm. On the other hand, progressive disease was best response in 44.8% of MK2206 versus 14.3% of everolimus-treated patients. MK-2206 induced significantly more rash and pruritis than everolimus, and dose reduction occurred in 37.9% of MK-2206 versus 21.4% of everolimus-treated patients. Genomic analysis revealed that 57.1% of the patients in the PD group had either deleterious TP53 mutations or ATM mutations or deletions. In contrast, none of the patients in the non-PD group had TP53 or ATM defects. No predictive marker for response was observed in this small dataset. Conclusions: Dichotomous outcomes are observed when VEGF therapy refractory patients are treated with MK-2206, and MK-2206 does not demonstrate superiority to everolimus. Additionally, mutations in DNA repair genes are associated with early disease progression, indicating that dysregulation of DNA repair is associated with a more aggressive tumor phenotype in RCC.
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Antineoplásicos/uso terapêutico , Carcinoma de Células Renais/tratamento farmacológico , Everolimo/uso terapêutico , Compostos Heterocíclicos com 3 Anéis/uso terapêutico , Neoplasias Renais/tratamento farmacológico , Idoso , Idoso de 80 Anos ou mais , Carcinoma de Células Renais/mortalidade , Intervalo Livre de Doença , Feminino , Humanos , Neoplasias Renais/mortalidade , Masculino , Pessoa de Meia-Idade , Resultado do TratamentoRESUMO
BACKGROUND: Ketoconazole is a well-known CYP17-targeted systemic treatment for castration-resistant prostate cancer (CRPC). However, most of the published data has been in the pre-chemotherapy setting; its efficacy in the post-chemotherapy setting has not been as widely described. Chemotherapy-naïve patients treated with attenuated doses of ketoconazole (200-300 mg three times daily) had PSA response rate (>50% decline) of 21-62%. We hypothesized that low-dose ketoconazole would likewise possess efficacy and tolerability in the CRPC post-chemotherapy state. METHODS: Men with CRPC and performance status 0-3, adequate organ function and who had received prior docetaxel were treated with low-dose ketoconazole (200 mg orally three times daily) and hydrocortisone (20 mg PO qAM and 10 mg PO qPM) until disease progression. Primary endpoint was PSA response rate (>50% reduction from baseline) where a rate of 25% was to be considered promising for further study (versus a null rate of <5%); 25 patients were required. Secondary endpoints included PSA response >30% from baseline, progression-free survival (PFS), duration of stable disease and evaluation of adverse events (AEs). RESULTS: Thirty patients were accrued with median age of 72 years (range 55-86) and median pre-treatment PSA of 73 ng ml(-1) (range 7-11,420). Twenty-nine patients were evaluable for response and toxicity. PSA response (>50% reduction) was seen in 48% of patients; PSA response (>30% reduction) was seen in 59%. Median PFS was 138 days; median duration of stable disease was 123 days. Twelve patients experienced grade 3 or 4 AEs. Of the 17 grade 3 AEs, only 3 were attributed to treatment. None of the two grade 4 AEs were considered related to treatment. CONCLUSIONS: In docetaxel pre-treated CRPC patients, low-dose ketoconazole and hydrocortisone is a well-tolerated, relatively inexpensive and clinically active treatment option. PSA response to low-dose ketoconazole appears historically comparable to that of abiraterone in this patient context. A prospective, randomized study of available post-chemotherapy options is warranted to assess comparative efficacy.
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Protocolos de Quimioterapia Combinada Antineoplásica/administração & dosagem , Hidrocortisona/administração & dosagem , Cetoconazol/administração & dosagem , Neoplasias de Próstata Resistentes à Castração/tratamento farmacológico , Taxoides/administração & dosagem , Idoso , Idoso de 80 Anos ou mais , Progressão da Doença , Intervalo Livre de Doença , Docetaxel , Humanos , Masculino , Pessoa de Meia-Idade , Antígeno Prostático Específico/sangue , Neoplasias de Próstata Resistentes à Castração/sangue , Neoplasias de Próstata Resistentes à Castração/patologia , Resultado do TratamentoRESUMO
To date, studies of irinotecan pharmacogenetics have mostly focused on the effect of the UGT1A1*28 allele on irinotecan-related toxicity. However, the clinical utility of routine UGT1A1*28 genotyping to pre-emptively adjust irinotecan dosage is dependent upon whether UGT1A1*28 also affects patient survival following irinotecan therapy. Previous observational studies evaluating the influence of UGT1A1*28 on survival have shown contradictory results. A systematic review and meta-analysis of both published and unpublished data were performed to summarize the available evidence of the relationship between the UGT1A1*28 allele and patient survival related to irinotecan therapy. Overall and progression-free survival meta-analysis data were available for 1524 patients and 1494 patients, respectively. The difference in the survival between patients of different UGT1A1*28 genotypes (homozygous, heterozygous or wild-type) who had received irinotecan was not found to be statistically significant. There was also no evidence of irinotecan dose, regimen or line of therapy having an impact on this association.
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Alelos , Camptotecina/análogos & derivados , Glucuronosiltransferase/genética , Neoplasias/tratamento farmacológico , Neoplasias/genética , Protocolos de Quimioterapia Combinada Antineoplásica/administração & dosagem , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Camptotecina/administração & dosagem , Camptotecina/uso terapêutico , Progressão da Doença , Genótipo , Humanos , Irinotecano , Análise de SobrevidaRESUMO
Macro-autophagy is associated with drug resistance in various cancers and can function as an adaptive response to maintain cell survival under metabolic stresses, including androgen deprivation. Androgen deprivation or treatment with androgen receptor (AR) signaling inhibitor (ARSI), Enzalutamide (MDV-3100, ENZA) or bicalutamide induced autophagy in androgen-dependent and in castration-resistant CaP (castration-resistant prostate cancer (CRPC)) cell lines. The autophagic cascade triggered by AR blockage, correlated with the increased light chain 3-II/I ratio and ATG-5 expression. Autophagy was observed in a subpopulation of C4-2B cells that developed insensitivity to ENZA after sustained exposure in culture. Using flow cytometry and clonogenic assays, we showed that inhibiting autophagy with clomipramine (CMI), chloroquine or metformin increased apoptosis and significantly impaired cell viability. This autophagic process was mediated by AMP-dependent protein kinase (AMPK) activation and the suppression of mammalian target of rapamycin (mTOR) through Raptor phosphorylation (Serine 792). Furthermore, small interfering RNA targeting AMPK significantly inhibited autophagy and promoted cell death in CaP cells acutely or chronically exposed to ENZA or androgen deprivation, suggesting that autophagy is an important survival mechanism in CRPC. Lastly, in vivo studies with mice orthotopically implanted with ENZA-resistant cells demonstrated that the combination of ENZA and autophagy modulators, CMI or metformin significantly reduced tumor growth when compared with control groups (P<0.005). In conclusion, autophagy is as an important mechanism of resistance to ARSI in CRPC. Antiandrogen-induced autophagy is mediated through the activation of AMPK pathway and the suppression of mTOR pathway. Blocking autophagy pharmacologically or genetically significantly impairs prostate cancer cell survival in vitro and in vivo, implying the therapeutics potential of autophagy inhibitors in the antiandrogen-resistance setting.
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Antagonistas de Receptores de Andrógenos/uso terapêutico , Autofagia/efeitos dos fármacos , Cloroquina/farmacologia , Clomipramina/farmacologia , Metformina/farmacologia , Feniltioidantoína/análogos & derivados , Animais , Benzamidas , Linhagem Celular Tumoral , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Humanos , Masculino , Camundongos , Camundongos SCID , Nitrilas , Feniltioidantoína/uso terapêutico , Neoplasias de Próstata Resistentes à Castração/tratamento farmacológico , Neoplasias de Próstata Resistentes à Castração/patologia , Transdução de Sinais/efeitos dos fármacos , Ensaios Antitumorais Modelo de XenoenxertoRESUMO
Akt is a serine/threonine kinase mediating multiple intracellular pathways involved in prostate cancer (CaP) biology. Increased understanding of the molecular mechanisms of Akt activation and signaling have led to the development of an increasing number of Akt inhibitors. These biologic agents demonstrate activity against a wide range of cancers in preclinical studies. Clinical studies of Akt inhibition in CaP are in progress, including agents such as celecoxib, perifosine and genistein. How best to integrate Akt inhibitors with standard CaP therapy or select patients most likely to benefit is the subject of ongoing research.
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Antineoplásicos/uso terapêutico , Neoplasias da Próstata/tratamento farmacológico , Proteínas Proto-Oncogênicas c-akt/antagonistas & inibidores , Transdução de Sinais/efeitos dos fármacos , Humanos , MasculinoRESUMO
The cellular signaling pathways of the prostate play a central role in the induction, maintenance, and progression of prostate cancer (CaP). Neuroendocrine (NE) cells demonstrate attributes that suggest they are an integral part of these signaling cascades. We summarize what is known regarding NE cells in CaP focusing on NE cellular transdifferentiation. This significant event in CaP progression appears to be accelerated by androgen deprivation (AD) treatment. We examine biochemical pathways that may impact NE differentiation in a chronological manner focusing on AD therapy (ADT) as a central event in inducing androgen-independent CaP. Our analysis is limited to the common adenocarcinoma pattern of CaP and excludes small-cell and carcinoid prostatic variants. In conclusion, we speculate on the future of treatment and research in this area.
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Adenocarcinoma/etiologia , Diferenciação Celular , Sistemas Neurossecretores/citologia , Sistemas Neurossecretores/fisiologia , Neoplasias da Próstata/etiologia , Adenocarcinoma/terapia , Animais , Humanos , Masculino , Modelos Biológicos , Neoplasias Hormônio-Dependentes/terapia , Neoplasias da Próstata/terapiaAssuntos
Biomarcadores Tumorais/análise , Marcadores Genéticos , Neoplasias Pulmonares/genética , Proteínas Musculares , Receptores ErbB/análise , Genes erbB-2 , Genes p53 , Genes ras , Humanos , Neoplasias Pulmonares/patologia , Proteínas dos Microfilamentos , Planejamento de Assistência ao Paciente , Prognóstico , Tubulina (Proteína)/análiseRESUMO
PURPOSE: Although expression of the HER-2/neu oncogene has been correlated with tumor progression in prostate cancer, the biologic significance of detecting HER-2/neu gene amplification by fluorescence in situ hybridization (FISH) or evidence for protein overexpression by immunohistochemistry (IHC) remains unclear. In this study, we directly compared HER-2/neu FISH and IHC to determine which may be more predictive of the response to trastuzumab. PATIENTS AND METHODS: Forty patients with prostate cancer were analyzed for gene amplification by FISH performed with HER-2/neu and chromosome 17 (CEP 17) DNA probes (Vysis). Protein expression was examined by immunofluorescence and by IHC using the DAKO HercepTest antibody protocol and a monoclonal antibody to Her-2/neu on archival paraffin sections. The patients included 30 men with primary tumors that were treated with radical prostatectomy. Of these, 15 demonstrated subsequent disease progression within 3 years. Five patients with prostatic intraepithelial neoplasia were tested, as were five with metastatic disease whose samples were obtained before androgen ablation therapy. RESULTS: None of the 30 primary prostate cancer specimens showed overexpression for HER-2/neu by immunofluorescence or by IHC with the DAKO protocol. One sample showed 3+ membrane expression with the monoclonal antibody. In contrast, low copy number gene amplifications (3-8 HER-2/neu signals/nucleus) were detected in 16 of 30 samples (53%) by FISH. Most amplified cells were diploid for CEP 17, demonstrating that amplification was not due to total cell aneuploidy. FISH and IHC determined that prostatic intraepithelial neoplasia samples were normal. Four of five (80%) metastatic samples were amplified for HER-2/neu by FISH. Nearly 70% of metastatic cancer cells among all five specimens demonstrated aneuploidy. A single lymph node metastasis showed 3+ membrane staining by IHC (DAKO). CONCLUSIONS: In contrast to breast cancer, FISH detects HER-2/neu amplification in a substantial proportion of prostate cancers that do not overexpress HER-2/neuby IHC. Although the biologic significance of this finding is uncertain, it has implications for the direction of current and planned clinical trials of trastuzumab in advanced prostate cancer, including determination of patient eligibility.
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Adenocarcinoma/genética , Genes erbB-2/genética , Neoplasias da Próstata/genética , Aneuploidia , Amplificação de Genes , Humanos , Hibridização in Situ Fluorescente , Masculino , Técnicas de Amplificação de Ácido NucleicoRESUMO
PURPOSE: Although cisplatin is an important agent in non-small-cell lung cancer (NSCLC), de novo resistance is common and acquired resistance emerges rapidly during therapy. Proposed mediators of platinum resistance include the protein kinase C (PKC) signal transduction pathway and associated c-FOS overexpression. While estrogen administration has been reported to upregulate PKC and c-FOS expression, the triphenylethylenes tamoxifen and toremifene potentiate platinum cytotoxicity by inhibition of PKC. Downregulation of c-FOS expression has been reported to result from PKC inhibition. In view of these findings, we hypothesized that toremifene would reverse platinum resistance and that this interaction would be influenced by tumor estrogen receptor (ER) status. MATERIALS AND METHODS: A phase II trial of high-dose toremifene (600 mg orally daily on days 1-7) plus cisplatin (50 mg/m2 intravenously on days 4 and 11) every 28 days in NSCLC patients was conducted. A group of 30 patients with metastatic NSCLC who had been previously treated with platinum-based therapy were enrolled. RESULTS: All of the 30 patients were assessable for toxicity and 28 for tumor response. Therapy was well tolerated with minimal hematologic and non-hematologic toxicity. Common toxicity criteria grade 3 hematologic toxicity was seen in only three patients. Five patients achieved a partial response for an overall response rate of 18% (95% CI 6-37). Median overall survival was 8.1 months (95% CI 5.4-17). To assess PKC, ER, and c-Fos expression by immunohistochemistry, 12 informative pretreatment patient tumor specimens were obtained. Four patient tumor specimens were positive for one or both PKC isoforms (alpha and epsilon) while c-Fos was overexpressed in three. None of the responding patient tumors exhibited c-FOS or PKC-epsilon overexpression. ER expression was found to be infrequent (8%), contrasting with previous reports in this tumor type. CONCLUSION: While this phase II study indicates that high-dose toremifene plus cisplatin is feasible, active, and well tolerated in NSCLC patients previously treated with platinum compounds, the mechanism of action remains unclear. Further study of this regimen is warranted.
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Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Cisplatino/administração & dosagem , Neoplasias Pulmonares/tratamento farmacológico , Toremifeno/administração & dosagem , Adulto , Idoso , Carcinoma Pulmonar de Células não Pequenas/mortalidade , Cisplatino/efeitos adversos , Feminino , Genes fos , Humanos , Neoplasias Pulmonares/mortalidade , Masculino , Pessoa de Meia-Idade , Proteína Quinase C/metabolismo , Toremifeno/efeitos adversosRESUMO
Randomized clinical trials have shown that combinations of chemotherapy plus thoracic radiation improve survival compared with radiotherapy alone in stage III non--small cell lung cancer (NSCLC). Furthermore, two recent studies have concluded that concurrent chemoradiotherapy produces superior results to sequential administration. Dependent on the dose and schedule used, chemotherapy may contribute by eradicating distant micrometastases by improving local control as a radiosensitizer, or through both mechanisms. In general, sequential approaches in which full-dose platinum-based chemotherapy precedes thoracic radiation or surgery have improved outcome by impacting distant metastases. In contrast, concurrent chemoradiotherapy using low-dose cisplatin is reported to improve survival by reducing local recurrence without an impact on distant failure rates. In view of these observations, chemoradiotherapy strategies integrating both radiosensitizing agents and dose levels of chemotherapy effective against micrometastases may prove to be most efficacious. Because distant metastases remain the major site of failure, it also is likely that more effective chemotherapy will be required to further improve the current level of response and survival. Fortunately, several newly available chemotherapeutic agents are both highly active against NSCLC and are potent radiosensitizers. In this report we review recent data regarding integration of new chemotherapeutic agents into chemoradiotherapy programs in stage III NSCLC, focusing on trials investigating docetaxel. Encouraging results, including those of the Southwest Oncology Group trial 9504, suggest that docetaxel will play a major role in the future of combined-modality therapy for locally advanced NSCLC. Semin Oncol 28 (suppl 9):26-32.
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Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Carcinoma Pulmonar de Células não Pequenas/radioterapia , Neoplasias Pulmonares/tratamento farmacológico , Neoplasias Pulmonares/radioterapia , Paclitaxel/análogos & derivados , Paclitaxel/uso terapêutico , Radiossensibilizantes/uso terapêutico , Taxoides , Carcinoma Pulmonar de Células não Pequenas/secundário , Carcinoma Pulmonar de Células não Pequenas/cirurgia , Terapia Combinada , Docetaxel , Esquema de Medicação , Feminino , Humanos , Neoplasias Pulmonares/secundário , Neoplasias Pulmonares/cirurgia , Masculino , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Paclitaxel/administração & dosagem , Radiossensibilizantes/administração & dosagem , Taxa de SobrevidaRESUMO
PURPOSE: Over 31,000 Americans die of androgen-independent metastatic prostate cancer each year. New strategies that do not involve hormonal manipulation but instead recognize the biochemical and molecular characteristics of prostate cancer are needed. Radioimmunotherapy (RIT) uses a tumor-specific monoclonal antibody to deliver systemic, targeted radiation to cancer. The objectives of this Phase I study of (111)In-2IT-BAD-m170 (for imaging) and (90)Y-2IT-BAD-m170 (for therapy) were to determine the toxicity and maximum tolerated dose (MTD), the specificity for targeting metastatic prostate cancer, and the efficacy for palliation of pain. EXPERIMENTAL DESIGN: M170 is a mouse monoclonal antibody that targets adenocarcinomas. Patients with adequate renal and liver function, rising prostate-specific antigen, and androgen-independent metastatic prostate cancer were eligible. After estimation of dosimetry and pharmacokinetics with (111)In-2IT-BAD-m170, a single dose of (90)Y-2IT-BAD-m170 (0.185, 0.370, 0.555, or 0.740 GBq/m(2)) was administered to cohorts of three patients. Pain was assessed objectively by questionnaires before and for 8 weeks after RIT; weekly prostate-specific antigen levels were obtained for 2 months after RIT. RESULTS: The MTD of (90)Y-2IT-BAD-m170 was 0.740 GBq/m(2) for patients that had up to 10% of the axial skeleton involved with prostate cancer. Toxicity was almost exclusively confined to reversible myelosuppression. Metastatic prostate cancer was targeted by (111)In-2IT-BAD-m170 in all 17 patients. The mean radiation dose delivered to 39 bone and 18 nodal metastases by (90)Y-2IT-BAD-m170 was 10.5 Gy/GBq (range 2.8-25.1). Thirteen of 17 patients reported pain before (90)Y-2IT-BAD-m170; 7 of these 13 had a partial or complete resolution of pain that lasted an average of 4.3 weeks. CONCLUSIONS: This study determined the MTD of (111)In/(90)Y-2IT-BAD-m170 in patients with metastatic prostate cancer. The drugs were well tolerated, targeted metastases, and temporarily palliated pain.
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Anticorpos Monoclonais/uso terapêutico , Terapia Combinada , Radioisótopos de Índio , Neoplasias da Próstata/terapia , Radioimunoterapia , Radioisótopos de Ítrio/uso terapêutico , Adenocarcinoma/terapia , Idoso , Animais , Anticorpos Monoclonais/farmacocinética , Estudos de Coortes , Humanos , Radioisótopos de Índio/farmacocinética , Masculino , Camundongos , Pessoa de Meia-Idade , Metástase Neoplásica , Dor/tratamento farmacológico , Antígeno Prostático Específico/biossíntese , Radiometria , Fatores de Tempo , Resultado do Tratamento , Radioisótopos de Ítrio/farmacocinéticaRESUMO
Clinical trials evaluating neoadjuvant or preoperative therapy for locally advanced non-small cell lung cancer (NSCLC) have demonstrated the feasibility, tolerability and activity of this approach. Three randomized trials have reported improved survival in patients with stage III NSCLC treated with preoperative chemotherapy followed by surgical resection compared to surgery alone. Combinations of neoadjuvant chemotherapy plus thoracic radiotherapy have also been investigated, generally resulting in higher rates of pathologic response, but higher toxicity rates as well. The best approach to neoadjuvant therapy remains to be determined and may well be substage dependent. In bulky stage III NSCLC, the role of surgery itself remains unclear and is the subject of an ongoing intergroup trial in the US. Regardless, neoadjuvant therapy has emerged as an important paradigm for clinical research since it serves as an in vivo test of chemosensitivity in patients, and represents a 'window of opportunity' for testing new chemotherapeutic agents and novel strategies. Among the new chemotherapeutic agents being investigated in this setting is docetaxel, one of the most active agents in first- and second-line chemotherapy of NSCLC, and a potent radiosensitizer. Preliminary studies have confirmed the feasibility of integrating docetaxel into neoadjuvant treatment strategies and encouraging results have been reported.
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Carcinoma Pulmonar de Células não Pequenas/terapia , Neoplasias Pulmonares/terapia , Terapia Neoadjuvante , Taxoides , Antineoplásicos Fitogênicos/uso terapêutico , Carcinoma Pulmonar de Células não Pequenas/patologia , Docetaxel , Humanos , Neoplasias Pulmonares/patologia , Estadiamento de Neoplasias , Paclitaxel/análogos & derivados , Paclitaxel/uso terapêutico , Ensaios Clínicos Controlados Aleatórios como AssuntoRESUMO
Combinations of gemcitabine (Gemzar) with cisplatin (Platinol) are among the most active new chemotherapy regimens developed for advanced non-small-cell lung cancer. Carboplatin (Paraplatin) is a platinum analog devoid of many of the nonhematologic toxicities associated with cisplatin. Although few direct comparisons have been made, when administered by area under the concentration-time curve (AUC) dosing, carboplatin is probably equivalent to cisplatin in advanced non-small-cell lung cancer and provides an improved therapeutic index. Based on its favorable toxicity profile, carboplatin has supplanted cisplatin for use in combination with paclitaxel in several different tumor types. Initial trials combining gemcitabine and carboplatin using standard days 1, 8, and 15 dosing of gemcitabine suggested that thrombocytopenia was problematic. More recently, 21-day schedules in which gemcitabine is administered only on days 1 and 8 have demonstrated both efficacy and improved toxicity profiles. Here we review recent studies investigating gemcitabine plus carboplatin and preliminary data regarding combinations of gemcitabine with the new platinum analog oxaliplatin.
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Antimetabólitos Antineoplásicos/uso terapêutico , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Desoxicitidina/análogos & derivados , Desoxicitidina/uso terapêutico , Humanos , Compostos de Platina/uso terapêutico , GencitabinaRESUMO
PURPOSE: Well-conducted cancer clinical trials are essential for improving patient outcomes. Unfortunately, only 3% of new cancer patients participate in clinical trials. Barriers to patient accrual in cancer clinical trials must be identified and overcome to increase patient participation. MATERIALS AND METHODS: We prospectively tracked factors that potentially affected patient accrual into cancer clinical trials at the University of California Davis Cancer Center. Oncologists seeing new outpatients were asked to complete questionnaires regarding patient characteristics and the physician's decision-making on patient eligibility, protocol availability, and patient opinions on participation. Statistical analysis was performed to correlate these parameters with subsequent protocol accrual. RESULTS: There were 276 assessable patients. At the initial visits, physicians did not consider clinical trials in 38% (105/276) of patients principally because of a perception of protocol unavailability and poor performance status. Physicians considered 62% (171/276) of patients for participation in clinical trials. Of these, only 53% (91/171) had an appropriate protocol available for site and stage of disease. Seventy-six of 90 patients (84%) with available protocols met eligibility criteria for a particular study. Only 39 of 76 patients (51%) agreed to participate in cancer clinical trials, for an overall accrual rate of 14% (39/276). The remainder (37/76, 49%) declined trial participation despite meeting eligibility criteria. The most common reasons were a desire for other treatment (34%), distance from the cancer center (13%), patient refusal to disclose reason (11%), and insurance denial (8%). Patients with private insurance were less likely to enroll in clinical trials compared to those with government-funded insurance (OR, 0.34; P =.03; 95% CI, 0.13 to 0.9). CONCLUSION: Barriers to cancer clinical trial accrual can be prospectively identified and addressed in the development and conduct of future studies, which may potentially lead to more robust clinical trials enrollment. Investigation of patient perceptions regarding the clinical trials process and the role of third party-payers is warranted.
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Ensaios Clínicos como Assunto , Seleção de Pacientes , Adolescente , Adulto , Idoso , Tomada de Decisões , Feminino , Geografia , Acessibilidade aos Serviços de Saúde , Humanos , Serviços de Informação , Cobertura do Seguro , Masculino , Pessoa de Meia-Idade , Participação do Paciente , Relações Médico-Paciente , Estudos ProspectivosRESUMO
Platinum compounds, either cisplatin (Platinol) or carboplatin (Paraplatin), in combination with a number of new chemotherapeutic agents, have demonstrated improved response or survival compared to cisplatin alone or older platinum-based regimens. Gemcitabine (Gemzar)-platinum combinations are of particular interest because of their interactive mechanisms of action, demonstrated preclinical synergism, and the single-agent activity of gemcitabine. Indeed, gemcitabine and cisplatin regimens have proven to be among the most efficacious in the palliative treatment of advanced non-small-cell lung cancer. In view of the reduced nonhematologic toxicities associated with the platinum analogue, carboplatin, several combinations of new agents and carboplatin have been developed and incorporated into clinical practice. This article describes recent clinical trials evaluating gemcitabine plus carboplatin, and the impact of the dosing schedule on the feasibility and tolerability of this combination.
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Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Desoxicitidina/análogos & derivados , Neoplasias Pulmonares/tratamento farmacológico , Cuidados Paliativos , Carboplatina/administração & dosagem , Desoxicitidina/administração & dosagem , Desoxicitidina/uso terapêutico , Relação Dose-Resposta a Droga , Esquema de Medicação , Humanos , Ensaios Clínicos Controlados Aleatórios como Assunto , Trombocitopenia/induzido quimicamente , GencitabinaRESUMO
Malignant thymomas are rare indolent tumours of the anterior superior mediastinum. Despite a benign histologic appearance, some thymomas invade nearby structures or metastasize. Patients are commonly asymptomatic, but some may present with unusual paraneoplastic syndromes such as myasthenia gravis, pure red cell aplasia, or hypogammaglobulinemia. Since tumour biopsy may potentially disrupt the thymic capsule, it is often not performed. Patients are therefore diagnosed and staged at the time of definitive surgery. Thymomas can generally be categorized into two stages: non-invasive and invasive. Prognosis closely parallels the disease stage. Surgery is the principal treatment and is curative in early stage disease. Radiation therapy, either alone or in combination with chemotherapy, is an option for both incompletely or completely resected disease. Chemotherapy is offered to patients with locally advanced, recurrent, or metastatic thymoma, with excellent responses and prolonged survival. Multicentre co-operative group clinical trials are required to assess novel thymoma therapies to maximize patient resources in this uncommon tumour.
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Timoma/diagnóstico , Timoma/terapia , Neoplasias do Timo/diagnóstico , Neoplasias do Timo/terapia , Terapia Combinada , Previsões , Humanos , Estadiamento de Neoplasias , Terapia de SalvaçãoRESUMO
Metastatic prostate cancer is a leading cause of cancer-related death in men. Although most patients will respond to androgen ablation as initial systemic therapy, nearly all patients will develop androgen-independent prostate cancer (AI CaP) and will succumb to the disease. Advances in molecular biology have demonstrated mutations in and persistent expression of the human androgen receptor in metastatic disease. Furthermore, recent evidence indicates that an apoptotic block through p53 mutations or bcl-2 overexpression may have a potential role in the poor responses seen with standard chemotherapy. Presently, the six general treatment options available for AI CaP are best supportive care, radiation therapy, radioisotopes, secondline hormonal therapy, chemotherapy (single agent or combination), and investigational therapies such as monoclonal antibodies, cyclin-dependent kinase inhibitors, matrix metalloproteinase inhibitors, and antiangiogenesis agents, among others. None of these modalities have produced durable remissions, although some have demonstrated palliative benefit. The next generation of clinical trials should not consist of futile hormonal manipulations or repetitive chemotherapy. Therapeutic strategies aimed at circumventing molecular blocks to cell death or targeting unique cancer molecules and genes will be more likely to improve quality of life and longevity. Furthermore, the aggressive use of palliative care will ensure effective caring for patients and the healing of families in the absence of cure.