Keratoacanthomas associated with sorafenib therapy.
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Biomedical subjects
Publications and source records attributed to William Dahut.
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PURPOSE: Docetaxel has activity against androgen-independent prostate cancer and preclinical studies have shown that taxane-based chemotherapy can enhance antitumor response of vaccines. The primary objective of this study was to determine if concurrent docetaxel (with dexamethasone) had any effect on generating an immune response to the vaccine. Secondary end points were whether vaccine could be given safely with docetaxel and the clinical outcome of the treatment regimen. EXPERIMENTAL DESIGN: The vaccination regimen was composed of (a) recombinant vaccinia virus (rV) that expresses the prostate-specific antigen gene (rV-PSA) admixed with (b) rV that expresses the B7.1 costimulatory gene (rV-B7.1), and (c) sequential booster vaccinations with recombinant fowlpox virus (rF-) containing the PSA gene (rF-PSA). Patients received granulocyte macrophage colony-stimulating factor with each vaccination. Twenty-eight patients with metastatic androgen-independent prostate cancer were randomized to receive either vaccine and weekly docetaxel or vaccine alone. Patients on the vaccine alone arm were allowed to cross over to receive docetaxel alone at time of disease progression. The ELISPOT assay was used to monitor immune responses for PSA-specific T cells. RESULTS: The median increase in these T-cell precursors to PSA was 3.33-fold in both arms following 3 months of therapy. In addition, immune responses to other prostate cancer-associated tumor antigens were also detected postvaccination. Eleven patients who progressed on vaccine alone crossed over to receive docetaxel at time of progression. Median progression-free survival on docetaxel was 6.1 months after receiving vaccine compared with 3.7 months with the same regimen in a historical control. CONCLUSION: This is the first clinical trial to show that docetaxel can be administered safely with immunotherapy without inhibiting vaccine specific T-cell responses. Furthermore, patients previously vaccinated with an anticancer vaccine may respond longer to docetaxel compared with a historical control of patients receiving docetaxel alone. Larger prospective clinical studies will be required to validate these findings.
BACKGROUND: The authors investigated whether prostate-specific antigen (PSA) velocity was associated significantly with the time to death after randomization among patients with hormone-refractory metastatic prostate carcinoma (HRMPC) who were treated with cytotoxic, cytotatic, or combination therapy. METHODS: The study cohort included 213 men with HRMPC who were treated on 3 prospective, randomized Phase II studies between February 1996 and October 2001. Cox regression analysis was used to evaluate whether there was a significant association between PSA velocity and the time to death after randomization, controlling for treatment and known prognostic factors. RESULTS: Increasing PSA velocity was associated significantly with shorter survival after randomization (P = 0.005) controlling for treatment and known prognostic factors. The adjusted hazard ratio for death was 1.8 (95% confidence interval [95% CI], 1.3-2.5; P = 0.0004) for men who had a PSA velocity > 0.0 ng/mL per month compared with men who had a PSA velocity < or = 0.0 ng/mL per month. Estimates of survival 2 years after randomization for these men were 16% (95% CI, 7-25%) and 44% (95% CI, 35-53%), respectively. CONCLUSIONS: PSA velocity was associated significantly with the length of survival among men with HRMPC who received cytotoxic, cytostatic, or combination therapy.
PURPOSE: Many patients with clinically localized prostate cancer develop biochemical failure despite excellent local therapy perhaps due to occult metastatic disease. One potential solution is the utilization of a well-tolerated systemic therapy (e.g., vaccine) in concert with local therapy. EXPERIMENTAL DESIGN: We present a randomized phase II clinical trial designed to determine if a poxviral vaccine encoding prostate-specific antigen (PSA) can induce a PSA-specific T-cell response when combined with radiotherapy in patients with clinically localized prostate cancer. Thirty patients were randomized in a 2:1 ratio into vaccine plus radiotherapy or radiotherapy-only arms. Those patients in the combination arm received a "priming" vaccine with recombinant vaccinia (rV) PSA plus r V containing the T-cell costimulatory molecule B7.1 (rV-B7.1) followed by monthly booster vaccines with recombinant fowlpox PSA. The vaccines were given with local granulocyte-macrophage colony-stimulating factor and low-dose systemic interleukin-2. Standard external beam radiation therapy was given between the fourth and the sixth vaccinations. RESULTS: Seventeen of 19 patients in the combination arm completed all eight vaccinations and 13 of these 17 patients had increases in PSA-specific T cells of at least 3-fold versus no detectable increases in the radiotherapy-only arm (P < 0.0005). There was also evidence of de novo generation of T cells to well-described prostate-associated antigens not found in the vaccine, providing indirect evidence of immune-mediated tumor killing. The vaccine was well tolerated. CONCLUSION: This vaccine regimen can be safely given in patients undergoing radiation therapy for localized prostate cancer, with the majority of patients generating a PSA-specific cellular immune response to vaccine.
OBJECTIVES: To evaluate whether the time to return to the baseline prostate-specific antigen (PSA) level (PSA response duration) is significantly associated with the time to death after randomization for men with hormone-refractory metastatic prostate cancer. METHODS: The study (n = 213) and validation (n = 281) cohorts constituted 494 men with hormone-refractory metastatic prostate cancer treated in four prospective randomized Phase II studies between February 1996 and October 2001. Cox regression analysis was used to evaluate whether a significant association existed between the PSA response duration and the time to death after randomization, controlling for treatment and known prognostic factors. RESULTS: A decreasing PSA response duration was significantly associated with a shorter survival after randomization in the study (P = 0.001) and validation (P = 0.02) cohorts, controlling for treatment and known prognostic factors, which included serum PSA, lactate dehydrogenase, alkaline phosphatase, and hemoglobin levels and the Eastern Cooperative Oncology Group performance status. The adjusted hazard ratio for death was 1.9 (95% confidence interval 1.4 to 2.6; P = 0.0002) and 2.1 (95% CI 1.2 to 3.5; P = 0.01) for men in the study and validation cohorts, respectively, whose PSA response duration was shorter than the median value of 3 months. The PSA response duration dichotomized about the median remained significantly associated with death whether patients in the validation cohort experienced at least a 50% reduction (P = 0.05) in the PSA level or not (P = 0.03). CONCLUSIONS: The duration of the PSA response to treatment is significantly associated with length of survival for men with hormone-refractory metastatic prostate cancer.
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PURPOSE: There is no current standard treatment for patients with prostate cancer who have received hormonal therapy but have an increasing prostate specific antigen (PSA) without radiographic evidence of metastasis. This trial was designed to analyze toxicity, immunogenicity and time to treatment failure using vaccine, antiandrogen therapy or their sequential use. MATERIALS AND METHODS: A total of 42 patients were randomized to receive vaccine vs antiandrogen therapy with nilutamide. The vaccine consisted of recombinant vaccinia viruses containing the PSA and B7.1 costimulatory genes as prime vaccinations, and avipox-PSA as boosters. After 6 months patients with an increasing PSA and no metastasis may receive a combination of both treatments. RESULTS: Three patients on nilutamide were removed from study secondary to grade 3 toxicities but no grade 3 toxicities were attributed to vaccine. In the vaccine arm median time to treatment failure was 9.9 months with 13 of 21 decreases in PSA velocity vs 7.6 months with 16 of 21 decreases in PSA velocity in the nilutamide arm (p =0.28). Of the patients in the nilutamide arm 8 had vaccine added at the time of PSA progression. Median time to treatment failure with combined therapy was 5.2 months, with a median duration from study entry of 15.9 months. Of the patients in the vaccine arm 12 had nilutamide added at the time of PSA progression. Median time to treatment failure with combined therapy was 13.9 months and a median of 25.9 months from initiation of therapy. CONCLUSIONS: Further studies are merited to investigate the role of combining vaccine with antiandrogen therapy or vaccine followed by vaccine plus antiandrogen therapy in this patient population.
The most common sites of metastatic disease from prostate cancer include the bones, lymph nodes and less commonly the lungs, adrenal glands, brain and kidneys. Acute fulminant hepatic failure secondary to cancer metastasis is rare and has unique clinical presentation. We describe a case of fatal liver failure in a 71-year-old male due to metastases to the liver from a prostatic adenocarcinoma. Thus in patients with metastatic cancer and elevated liver function tests, the possibility of hepatic involvement by the cancer should be considered as a possible cause of hepatic failure.
PURPOSE: This study was undertaken to determine the toxicities, pharmacokinetics, and maximum tolerated doses of oxaliplatin in patients with renal impairment and to develop formal guidelines for oxaliplatin dosing in this patient population. PATIENTS AND METHODS: Thirty-seven adult cancer patients with variable renal function received intravenous oxaliplatin at 60 to 130 mg/m2 every 3 weeks. Patients were stratified by 24-hour creatinine clearance (CrCL) into four cohorts: group A (controls, CrCL > or =60 mL/min), group B (mild dysfunction, CrCL 40 to 59 mL/min), group C (moderate dysfunction, CrCL 20 to 39 mL/min), and group D (severe dysfunction, CrCL <20 mL/min). Doses were escalated in cohorts of three patients, and urine and plasma ultrafiltrates were assayed for platinum concentrations. RESULTS: No dose-limiting toxicities were observed in any patient group during the first cycle of therapy. Escalation of oxaliplatin to the maximum dose of 130 mg/m2 was well tolerated in all patient groups with a CrCL > or =20 mL/min (groups A, B, and C). Pharmacokinetic analysis showed that patients with decreased CrCL had a corresponding decrease in the clearance of plasma ultrafiltrable platinum (r2 = 0.765). However, oxaliplatin-induced side effects were not more common or severe in patients with mild to moderate renal dysfunction, despite the decrease in ultrafiltrable platinum clearance. CONCLUSION: Oxaliplatin at 130 mg/m2 every 3 weeks is well tolerated by patients with mild to moderate degrees of renal dysfunction. These data strongly support the recommendation that dose reductions of single-agent oxaliplatin are not necessary in patients with a CrCL greater than 20 mL/min.
PURPOSE: A phase I pharmacologic study was undertaken to determine the maximum tolerated dose (MTD), to characterize the pharmacokinetic profile, and to evaluate all toxicities of the aqueous colloidal dispersion formulation of 9-aminocampothecin (9-AC). METHODS: 9-AC was administered as a constant 72-h i.v. infusion every 2 weeks to adult cancer patients at dose rates ranging from 25 to 59 microg/m2 per hour. RESULTS: Twenty patients with refractory solid tumors received a total of 86 courses of 9-AC at four dose levels. Myelosuppression, particularly granulocytopenia, was the most common toxicity. Two of six assessable patients entered at 59 microg/m2 per hour had dose-limiting toxicity (grade 3 diarrhea or need for a 2-week treatment delay to permit granulocyte recovery), whereas lower doses were well tolerated. At the recommended dose, 47 microg/m2 per hour, the average steady-state plasma levels (Cpss) and area under the curve (AUC) of 9-AC lactone and total drug were 15 and 75 nM, and 1034 and 4220 nM.h, respectively. A moderate correlation was seen between 9-AC lactone AUC and the percentage decrease in granulocytes. CONCLUSIONS: The recommended phase II dose of 9-AC colloidal dispersion as a 72-h infusion every 14 days is 47 microg/m2 per hour (1.13 mg/m2 per day). The Cpss of 9-AC lactone at this dose exceeded the 10 nM threshold level for preclinical activity.
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In this phase I/II clinical trial the antitumor activity of high-dose tamoxifen when administered in combination with vinblastine was assessed and the toxicity profile of this combination characterized. All 25 patients enrolled in this study were required to have androgen-independent prostate cancer and to maintain androgen ablation during treatment. Vinblastine was given by continuous infusion over 5 days. Doses were increased from 0.9 mg/m2/day to 1.5 mg/m2/day in successive cohorts of at least 3 patients, with no further escalation even in the absence of dose-limiting toxicity. Intra-patient dose escalation was permitted. Tamoxifen was administered at a dose of 200 mg/kg on day 1, then 120 mg/kg/day on day 2. Standard response criteria were utilized to assess antitumor activity and CTC toxicity criteria were used. Quality of life (QOL) pain assessments were evaluated at each visit to the clinic. Most patients tolerated the highest dose of vinblastine at 1.5 mg/m2/day by continuous infusion over 5 days with 200 mg/kg/day of tamoxifen on day 1 and day 2. One patient had a greater than 50% decline in prostate-specific antigen that lasted for 170 days. Two patients received dose reductions because of toxicity. The most common serious toxicities included neutropenia, and fatigue. Reversible neurosensory, neuromotor, neurocortical and neurocerebellar toxicities were reported. Six of the 25 patients enrolled in the study (24%) experienced reversible neurologic toxicity of at least grade III. No statistically significant differences between precycle assessment of QOL and subsequent cycles were observed. It is concluded that vinblastine at 1.5 mg/m2/day continuous i.v. infusion combined with tamoxifen 200 mg/kg/day on day 1 and day 2 is inactive, and not without toxicity in the treatment of advanced metastatic androgen-independent prostate cancer.
BACKGROUND: A Phase I trial of recombinant vaccinia prostate specific antigen (rV-PSA) in patients with advanced metastatic prostate cancer was conducted. This report describes 42 patients who were treated with up to three monthly vaccinations. METHODS: All patients were entered on a dose-escalation phase I study of recombinant vaccinia containing the gene for PSA (rV-PSA). The primary objective of this study was to determine the safety of this vaccine in metastatic androgen-independent prostate cancer patients. A secondary objective was to assess evidence of anti-tumor activity by PSA measurements, radiologic findings, and immunologic methods. RESULTS: There was no significant treatment-related toxicity apart from erythema, tenderness, and vesicle formation that lasted several days at the site of injection in some patients. There were immunologic responses, in selected patients, as evidenced by an increase in the proportion of PSA-specific T cells after vaccination. Furthermore, we show that these patients' T cells can lyse PSA-expressing tumor cells in vitro. CONCLUSION: Given the low toxicity profile and the evidence of immunologic activity, we believe future study is warranted with PSA-based vaccines in prostate cancer. New PSA-based vaccines and vaccine strategies are currently being evaluated.
Suramin, a polysulphonated napthylurea, has been extensively evaluated over the past 10 years as an anticancer agent, with the most interest in the treatment of prostate cancer. Early clinical results were promising with response rates of up to 70% being reported. However, a recent double-blind study showed only modest palliative effect in patients with androgen independent prostate cancer. In retrospect, it appears those initial reports failed to control for confounding variables such as antiandrogen withdrawal and hydrocortisone. Suramin causes numerous reversible toxicities (lethargy, rash, fatigue, anemia, hyperglycemia, hypocalcemia, coagulopathies, neutropenia, renal and hepatic complications). Neurotoxicity has been the most significant complication and appears to be related to the intensity of the dosing regimen. An optimal therapeutic dose has not been determined, but it is clear that adaptive controls add little benefit. Aside from moderate toxicities and the low therapeutic index in patients with prostate cancer, suramin's development has taught us some valuable lessons (i.e., anti-androgen withdrawal was noted during suramin's development, the use of PSA as an indicator of tumor burden was initiated during the evaluation of suramin). These lessons can be applied to all clinical trials in hormone refractory prostate cancer. Suramin has significantly enhanced the evolution of our knowledge in several areas of prostate cancer biology and treatment.
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Current treatments for androgen-independent prostate cancer have not shown a definitive increase in survival. Several novel drugs have made their way through preclinical testing into early clinical trials. Targets discussed in this review include apoptosis, antiangiogenesis, growth factor receptors or associated tyrosine kinases, and tumor-associated antigens targeted by vaccines. Research in this area includes testing combinations of previously studied chemotherapeutic agents as well as identifying and testing novel agents. It is these drugs, either alone or in combination, that are designed to target strategic pathways to improve survival and increase quality of life in prostate cancer patients. This review focuses on the novel agents being tested with chemotherapy in metastatic prostate cancer.
Adenocarcinoma of the prostate is the most common cancer diagnosed in men in the United States, with approximately 189,000 new cases estimated to be diagnosed in 2002. It is believed that men with this disease pass through a series of clinical states. In the intramural program of the National Cancer Institute, we have designed clinical trials that have addressed each disease state. In addition to clinical endpoints, each trial also encompasses molecular or immunologic endpoints in an attempt to determine if our therapy is acting on its presumed target. In patients with localized disease, we are evaluating cancer vaccines in combination with radiation therapy as well as comparing this vaccine against second-line hormonal therapy in patients with rising serum prostate-specific antigen (PSA) but no radiographically measurable disease. We are also evaluating the ability of the antiangiogenesis agent thalidomide to prolong the rest period in patients with a biochemical recurrence (stage D0) that are receiving intermittent hormonal therapy. In patients with metastatic prostate cancer, we are evaluating the addition of the bisphosphonate alendronate when added to ketoconazole for impact on matrix metalloproteinase (MMP)-2 and MMP-9 as well as traditional clinical endpoints. In addition, we have 3 ongoing trials involving the chemotherapeutic agent docetaxel. One trial is examining the combination of thalidomide with docetaxel. The other 2 trials are exploring the PSA vaccine with docetaxel and the combination of docetaxel with ketoconazole. As we obtain information from these ongoing studies, we will be able to take this information and integrate it in the development of newer and more successful treatment regimens as well as look for novel agents that may help in the fight against this disease.
PURPOSE: Monitoring of androgen independent prostate cancer (AIPC) therapy involves monitoring prostate specific antigen (PSA) blood serum concentrations; however, the reliability of small changes in PSA values has been questioned. We performed a small pilot study to determine whether PET might be a useful monitor of changes during anti-angiogenic therapy in AIPC. PROCEDURES: Changes in tumor blood flow ([15O] water), blood volume ([11C]CO), 2-deoxy-2-[18F]fluoro-D-glucose (FDG) uptake and metabolic volume were measured before and during thalidomide treatment and compared with changes in PSA in six patients with AIPC. RESULTS: The percent change in PSA correlated with the FDG Delta%SUV(mean) (r=0.94, P<0.01) and Delta%metabolic tumor volume (r=0.91, P<0.01) but less well with Delta%blood volume (r=0.65, P=0.14). Percent change blood flow values showed an inverse correlation with percent changes in PSA (r=-0.83, P=0.032). CONCLUSIONS: PET measures of tumor blood flow and metabolism may have use in monitoring the physiologic changes occurring during anti-angiogenic therapy in AIPC.