Safety of celecoxib in individuals allergic to sulfonamide: a pilot study.

OBJECTIVE: To evaluate cross reactivity between sulfonamide antimicrobials and celecoxib in patients with histories of allergies to sulfonamide antimicrobials. METHODS: Immunocompetent patients with a history of sulfonamide antimicrobial allergy who were being considered for therapy with celecoxib were prospectively enrolled. Sulfamethoxazole and trimethoprim skin prick and intradermal testing and/or an in vitro lymphocyte toxicity assay were performed. If skin testing was negative, an oral challenge with sulfamethoxazole and trimethoprim was performed. Oral challenges with celecoxib were administered to all patients. RESULTS: Twenty-eight immunocompetent patients (26 female; mean age 60 years) were evaluated. History of sulfonamide antimicrobial allergy included urticaria (n = 7), cutaneous eruptions (n = 9), and other (n = 12). Four of the 28 patients who were skin prick tested were positive to sulfamethoxazole and two of the ten patients who underwent in vitro testing were positive to sulfamethoxazole. All 28 patients were administered celecoxib and tolerated the medication. Phone call follow up in 25 patients disclosed that 15 patients continued to take celecoxib, while five patients did not take celecoxib following the oral challenge, and five discontinued celecoxib due to adverse effects, lack of drug efficacy or physician preference. CONCLUSIONS: Confusion exists regarding the potential for cross reactivity between sulfonamide antimicrobials and other sulfonamide-containing compounds. The six sulfonamide-allergic patients tolerated celecoxib uneventfully. This pilot study supports the hypothesis that the potential for cross-reactivity between celecoxib and sulfonamide antimicrobials appears to be low. However, further investigations are required to confirm this.     

Quantitation of motexafin lutetium in human plasma by liquid chromatography-tandem mass spectrometry and inductively coupled plasma-atomic emission spectroscopy

Liquid chromatography-tandem mass spectrometry (LC-MS/MS) and inductively coupled plasma-atomic emission spectroscopy (ICP-AES) methods were developed and validated for the evaluation of motexafin lutetium (MLu, lutetium texaphyrin, PCI-0123) pharmacokinetics in human plasma. The LC-MS/MS method was specific for MLu, whereas the ICP-AES method measured total elemental lutetium. Both methods were fast, simple, precise, and accurate. For the LC-MS/MS method, a closely related analogue (PCI-0353) was used as the internal standard (IS). MLu and the IS were extracted from plasma by protein precipitation and injected onto and LC-MS/MS system configured with a C18 column and an electrospray interface. The lower limit of quantitation was 0.05 μg MLu mL⁻¹, with a signal-to-noise ratio of 15∶1. The response was linear from 0.05 to 5.0 μg MLu mL⁻¹. For the ICP-AES method, indium was used as the IS. The sample was digested with nitric acid, diluted, filtered, and then injected onto the ICP-AES system. Two standard curve ranges were validated to meet the expected range of sample concentrations: 0.5 to 50, and 0.1 to 10 μg Lu mL⁻¹. The LC-MS/MS and ICP-AES methods were validated to establish accuracy, precision, analyte stability, and assay robustness. Interday precision and accuracy of quality control samples were ≤6.3% coefficient of variation (CV) and within 2.2% relative error (RE) for the LC-MS/MS method, and ≤8.7% CV and within 4.9% RE for the ICP-AES method. Plasma samples from a subset of patients in a clinical study were analyzed using both methods. For a representative patient, over 90% of the elemental lutetium in plasma could be ascribed to intact MLu at early time points. This percentage decreased to 59% at 48 hours after dosing, suggesting that some degradation and/or metabolism of the drug may have occurred.     

Outcomes of a randomized trial of hyperfractionated cranial radiation therapy for treatment of high-risk acute lymphoblastic leukemia: therapeutic efficacy and neurotoxicity.

PURPOSE: We evaluated 8-year survival and late neuropsychologic toxicity in children with acute lymphoblastic leukemia treated in a randomized clinical trial to test whether hyperfractionated (twice daily) cranial radiation therapy (CRT) can reduce incidence and severity of late toxicities associated with 18 Gy of CRT. PATIENTS AND METHODS: Between 1987 and 1995, 369 children treated on two consecutive Dana-Farber Cancer Institute Consortium protocols for high-risk acute lymphoblastic leukemia were randomly assigned to conventionally fractionated CRT (CFX) or hyperfractionated CRT (HFX) to a total dose of 18 Gy. Neuropsychologic testing was completed for 125 of 287 children in continuous complete remission. Event-free and overall survival, as well as neuropsychologic function, were compared for the two arms of the protocol. RESULTS: Eight-year event-free survival (+/- SE) was 80% +/- 3% for children randomly assigned to CFX and 72% +/- 3% for HFX (P =.06). Overall survival was 85% +/- 3% for CFX and 78% +/- 3% for HFX (P =.06). CNS relapses occurred in 2.8% of patients receiving CFX and 2.7% receiving HFX (P =.99). Cognitive function for both groups was solidly in the average range, with no group differences in intelligence, academic achievement, visuospatial reasoning, or verbal learning. Children on the HFX arm exhibited a modest advantage for visual memory (P <.05). CONCLUSION: HFX provides no benefit in terms of cognitive late effects and may compromise antileukemic efficacy. HFX should not be substituted for conventionally dosed CRT in children who require radiation therapy for treatment of acute lymphoblastic leukemia.     

Antibody-based profiling of the phosphoinositide 3-kinase pathway in clinical prostate cancer.

PURPOSE: As kinase inhibitors transition from the laboratory to patients, it is imperative to develop biomarkers that can be used in the clinic. The primary objectives are to identify patients most likely to benefit from molecularly targeted therapies and to document modulation of the drug target. Constitutive activation of the phosphoinositide 3-kinase (PI3K) pathway and its downstream effectors, as a result of PTEN loss or by other mechanisms, occurs in a high proportion of prostate cancers, making it an ideal template for the design of clinical trials involving PI3K pathway inhibitors. Prostate cancers also present unique organ-specific challenges, in that tumors are heterogeneous and diagnostic tissue is extremely limited. EXPERIMENTAL DESIGN: Working within these limitations, we have developed a set of immunohistochemical assays that define activation of the PI3K pathway in clinical samples. Results and CONCLUSIONS: Using both univariate and multivariate analyses, we show that loss of PTEN is highly correlated with the activation of AKT, and this, in turn, is associated with the phosphorylation of S6, one of its main effectors. These three antibodies are potentially able to define a molecular signature of PTEN loss and/or AKT pathway activation in prostate cancer.     

Computed tomography (CT) evaluation of breast cancer patients with osteolytic bone metastases undergoing palliative radiotherapy—a feasibility study

Twenty-five patients with osteolytic metastases had computed tomography (CT) scans before and 3 months after palliative radiotherapy. The median % density change following single 8 Gy, 20 Gy/5#, 30 Gy/10# were: 128 (range 98–255), 141 (79–342), and 145 (65–235), respectively. It is feasible to evaluate remineralization of osteolytic lesions with palliative radiotherapy.     

Serologic evidence of human papillomavirus 16 and 18 infections and risk of prostate cancer.

Human papillomavirus (HPV) subtypes 16 and 18 are sexually transmitted and have been associated with an increased incidence of several anogenital tumors. Although previous epidemiological studies have suggested that sexual behaviors such as an early age at first intercourse and larger numbers of sexual partners are also related to an increased risk of prostate cancer, seroepidemiological studies of these infectious agents in relation to prostate cancer have produced differing results. To further evaluate this potential relationship, we completed a population-based control study in King County, Washington. Middle-aged (40-64 years) men diagnosed with prostate cancer (n = 642) were ascertained through the Seattle-Puget Sound Surveillance, Epidemiology, and End Results cancer registry between January 1993 and December 1996. Controls (n = 570) of similar age were selected from the same population as the cases by random digit dialing. Overall, there was no association between serological evidence of prior HPV-16 (adjusted odds ratio, 1.06; 95% confidence interval, 0.71-1.57) or HPV-18 (adjusted odds ratio, 1.36; 95% confidence interval, 0.69-2.69) infection and the risk of prostate cancer. Analyses of clinical features demonstrated no relationship between HPV infection status and Gleason score, stage of disease, or a combined measure of disease aggressiveness. Our findings indicate that HPV-16 and HPV-18 are not associated with prostate cancer risk.     

Association of HPC2/ELAC2 polymorphisms with risk of prostate cancer in a population-based study.

Genetic polymorphism in HPC2/ELAC2 was recently associated with risk of sporadic prostate cancer. To determine the contribution of two HPC2/ELAC2 missense variants (Ser217Leu and Ala541Thr) to the risk of developing prostate cancer, we conducted a population-based case-control study of middle-aged men (40-64 years). Cases (n=591) were ascertained from the Seattle-Puget Sound Surveillance, Epidemiology, and End Results Cancer Registry and Controls (n=538) from the same general population were identified through random-digit dialing. Subjects were residents of King County, Washington, and were frequency matched on age. Cases (32%) had a slightly higher frequency of the Leu217 variant compared with controls (29%), but there were no differences in the frequency of the Thr541 allele (4%). When considering joint genotypes, white men homozygous for the Leu217 variant on an Ala541/Ala541 background had an increased risk of prostate cancer [odds ratio (OR)=1.84; 95% confidence interval (CI), 1.11-3.06]. Different risk profiles were also observed when cases were stratified by disease aggressiveness. Men with at least one Leu217 allele had an elevated risk (OR=1.34; 95% CI, 1.02-1.76) of less aggressive prostate cancer (localized stage and Gleason score < or = 7), with a stronger association among men with two Leu217 alleles (OR=1.73; 95% CI, 1.08-2.77). The Ala541Thr polymorphism was not associated with risk, and neither variant was associated with more aggressive prostate cancer phenotypes. We estimate that the Ser217Leu genotype may account for approximately 14% of less aggressive prostate cancer cases and 9% of all sporadic cases in the general United States population of white men 相似文献