A pharmacokinetic interaction study of docetaxel and cisplatin plus or minus 5-fluorouracil in the treatment of patients with recurrent or metastatic solid tumors

BACKGROUND: The purpose of this study was to look at the pharmacokinetics of docetaxel, cisplatin-derived platinum and 5-fluorouracil (5-FU), when used in combination, to exclude potential clinically relevant pharmacokinetic interactions. METHODS: Fifteen patients with recurrent or metastatic solid tumors were randomized to receive docetaxel 75 mg/m2 and cisplatin 75 mg/m2 in the first treatment course on day 1 and the same combination plus 5-FU 750 mg/m2/day on days 1-5 in the second course, or the two treatment courses in reversed order. Cycles were repeated every 3 weeks. A pharmacokinetic analysis was performed during the first two cycles. RESULTS: Full pharmacokinetic data was available for 12 of the 15 patients. Treatment was tolerated well, with frequency of toxicity consistent with the safety profile known for docetaxel, cisplatin and 5-FU. Mean clearance values for docetaxel and cisplatin showed no statistically significant difference across the "triple" and the "double" combination treatments, and the mean pharmacokinetic parameters of all agents were within the ranges for previously reported single agent treatment. CONCLUSION: No clinically relevant pharmacokinetic interactions between docetaxel, cisplatin and 5-FU used in combination were noticed in this study

Casein Kinase 2α Regulates Multidrug Resistance-Associated Protein 1 Function via Phosphorylation of Thr249

We have shown previously that the function of Ycf1p, yeast ortholog of multidrug resistance-associated protein 1 (MRP1), is regulated by yeast casein kinase 2α (Cka1p) via phosphorylation at Ser251. In this study, we explored whether casein kinase 2α (CK2α), the human homolog of Cka1p, regulates MRP1 by phosphorylation at the semiconserved site Thr249. Knockdown of CK2α in MCF7-derived cells expressing MRP1 [MRP1 CK2α(−)] resulted in increased doxorubicin sensitivity. MRP1-dependent transport of leukotriene C(4) and estradiol-17β-d-glucuronide into vesicles derived from MRP1 CK2α(−) cells was decreased compared with MRP1 vesicles. Moreover, mutation of Thr249 to alanine (MRP1-T249A) also resulted in decreased MRP1-dependent transport, whereas a phosphomimicking mutation (MRP1-T249E) led to dramatic increase in MRP1-dependent transport. Studies in tissue culture confirmed these findings, showing increased intracellular doxorubicin accumulation in MRP1 CK2α(−) and MRP1-T249A cells compared with MRP1 cells. Inhibition of CK2 kinase by 2-dimethylamino-4,5,6,7-tetrabromo-1H-benzimidazole resulted in increased doxorubicin accumulation in MRP1 cells, but not in MRP1 CK2α(−), MRP1-T249A, or MRP1-T249E cells, suggesting that CK2α regulates MRP1 function via phosphorylation of Thr249. Indeed, CK2α and MRP1 interact physically, and recombinant CK2 phosphorylates MRP1-derived peptide in vitro in a Thr249-dependent manner, whereas knockdown of CK2α results in decreased phosphorylation at MRP1-Thr249. The role of CK2 in regulating MRP1 was confirmed in other cancer cell lines where CK2 inhibition decreased MRP1-mediated efflux of doxorubicin and increased doxorubicin cytotoxicity. This study supports a model in which CK2α potentiates MRP1 function via direct phosphorylation of Thr249

Validation and reliability of the Dutch version of the EORTC QLQ-BLM30 module for assessing the health-related quality of life of patients with muscle invasive bladder cancer

Background: Quality of Life (QoL) of bladder cancer patients has been largely neglected. This is partly due to the lack of well-validated QoL questionnaires. The aim of this study is to examine the structural validity, reliability (i.e., internal consistency and test-retest reliability), construct validity (i.e., divergent validity and known group validity) and responsiveness of the Dutch version of the European Organisation for Research and Treatment of Cancer QoL questionnaire for muscle invasive bladder cancer (EORTC-QLQ-BLM30). Methods: Patients with newly diagnosed muscle invasive bladder cancer (MIBC) participating in the population-based ‘Blaaskankerzorg In Beeld’ (BlaZIB) study who completed the EORTC-QLQ-BLM30 at baseline were included. BlaZIB is a Dutch nationwide population-based prospective cohort study collecting clinical data and QoL data of bladder cancer patients. QoL is assessed with a self-administered questionnaire at four points in time: 6 weeks (baseline), 6 months, 12 months and 24 months after diagnosis. Confirmatory factor analysis and multitrait scaling analysis were used to investigate and adapt the scale structure. Reliability, construct validity and responsiveness of the revised scales were evaluated. Results: Of the 1542 patients invited to participate, 650 patients (42.2%) completed the QLQ-BLM30 at baseline. The questionnaire’s scale structure was revised into seven scales and eight single items. Internal consistency and test-reliability were adequate for most scales (Cronbach’s α ≥0.70 and intraclass correlation coefficient ≥ 0.70, respectively), with the exception of the revised urostomy problem scale and abdominal bloating and flatulence scale. The questionnaire exhibited little overlap with the EORTC-QLQ-C30: all correlations were < 0.40, except for the correlation between emotional function (QLQ-C30) and future worries (QLQ-BLM30). The questionnaire was able to distinguish between patient subgroups formed on the basis of physical function, but not – as hypothesized– based on stage. Changes in health due to treatment were captured by the questionnaire, indicating that the questionnaire is responsive to change. Conclusions: This study shows that the adapted scale structure of the EORTC-QLQ-BLM30 generally exhibits good measurement properties in Dutch patients, but needs to be validated in other languages and settings. Trial registration: BlaZIB, NL8106, www.trialregister.nl

Robot-assisted Versus Open Radical Cystectomy in Bladder Cancer:An Economic Evaluation Alongside a Multicentre Comparative Effectiveness Study

Background: Open radical cystectomy (ORC) is regarded as the standard treatment for muscle-invasive bladder cancer, but robot-assisted radical cystectomy (RARC) is increasingly used in practice. A recent study showed that RARC resulted in slightly fewer minor but slightly more major complications, although the difference was not statistically significant. Some differences were found in secondary outcomes favouring either RARC or ORC. RARC use is expected to increase in coming years, which fuels the debate about whether RARC provides value for money.Objective: To assess the cost-effectiveness of RARC compared to ORC in bladder cancer. Design, setting, and participants: This economic evaluation was performed alongside a prospective multicentre comparative effectiveness study. We included 348 bladder cancer patients (ORC, n = 168; RARC, n = 180) from 19 Dutch hospitals. Outcome measurements and statistical analysis: Over 1 yr, we assessed the incremental cost per quality-adjusted life year (QALY) gained from both healthcare and societal perspectives. We used single imputation nested in the bootstrap percentile method to assess missing data and uncertainty, and inverse probability of treatment weighting to control for potential bias. Deterministic sensitivity analyses were performed to explore the impact of various parameters on the cost difference. Results and limitations: The mean healthcare cost per patient was €17 141 (95% confidence interval [CI] €15 791–€18 720) for ORC and €21 266 (95% CI €19 163–€23 650) for RARC. The mean societal cost per patient was €18 926 (95% CI €17 431–€22 642) for ORC and €24 896 (95% CI €21 925–€31 888) for RARC. On average, RARC patients gained 0.79 QALYs (95% CI 0.74–0.85) compared to 0.81 QALYs (95% CI 0.77–0.85) for ORC patients, resulting in a mean QALY difference of −0.02 (95% CI −0.05 to 0.02). Using a cost-effectiveness threshold of €80 000, RARC was cost-effective in 0.6% and 0.2% of the replications for the healthcare and societal perspectives, respectively. Conclusions: RARC shows no difference in terms of QALYs, but is more expensive than ORC. Hence, RARC does not seem to provide value for money in comparison to ORC. Patient summary: This study assessed the relation between costs and effects of robot-assisted surgery compared to open surgery for removal of the bladder in 348 Dutch patients with bladder cancer. We found that after 1 year, the two approaches were similarly effective according to a measure called quality-adjusted life years, but robot-assisted surgery was much more expensive. This trial was prospectively registered in the Netherlands Trial Register as NTR5362 (https://www.trialregister.nl/trial/5214).</p

Robot-assisted Versus Open Radical Cystectomy in Bladder Cancer: An Economic Evaluation Alongside a Multicentre Comparative Effectiveness Study

Background: Open radical cystectomy (ORC) is regarded as the standard treatment for muscle-invasive bladder cancer, but robot-assisted radical cystectomy (RARC) is increasingly used in practice. A recent study showed that RARC resulted in slightly fewer minor but slightly more major complications, although the difference was not statistically significant. Some differences were found in secondary outcomes favouring either RARC or ORC. RARC use is expected to increase in coming years, which fuels the debate about whether RARC provides value for money. Objective: To assess the cost-effectiveness of RARC compared to ORC in bladder cancer. Design, setting, and participants: This economic evaluation was performed alongside a prospective multicentre comparative effectiveness study. We included 348 bladder cancer patients (ORC, n = 168; RARC, n = 180) from 19 Dutch hospitals. Outcome measurements and statistical analysis: Over 1 yr, we assessed the incremental cost per quality-adjusted life year (QALY) gained from both healthcare and societal perspectives. We used single imputation nested in the bootstrap percentile method to assess missing data and uncertainty, and inverse probability of treatment weighting to control for potential bias. Deterministic sensitivity analyses were performed to explore the impact of various parameters on the cost difference. Results and limitations: The mean healthcare cost per patient was €17 141 (95% confidence interval [CI] €15 791–€18 720) for ORC and €21 266 (95% CI €19 163–€23 650) for RARC. The mean societal cost per patient was €18 926 (95% CI €17 431–€22 642) for ORC and €24 896 (95% CI €21 925–€31 888) for RARC. On average, RARC patients gained 0.79 QALYs (95% CI 0.74–0.85) compared to 0.81 QALYs (95% CI 0.77–0.85) for ORC patients, resulting in a mean QALY difference of −0.02 (95% CI −0.05 to 0.02). Using a cost-effectiveness threshold of €80 000, RARC was cost-effective in 0.6% and 0.2% of the replications for the healthcare and societal perspectives, respectively. Conclusions: RARC shows no difference in terms of QALYs, but is more expensive than ORC. Hence, RARC does not seem to provide value for money in comparison to ORC. Patient summary: This study assessed the relation between costs and effects of robot-assisted surgery compared to open surgery for removal of the bladder in 348 Dutch patients with bladder cancer. We found that after 1 year, the two approaches were similarly effective according to a measure called quality-adjusted life years, but robot-assisted surgery was much more expensive. This trial was prospectively registered in the Netherlands Trial Register as NTR5362 (https://www.trialregister.nl/trial/5214)