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Aims: To describe the sources of interindividual variability of bevacizumab and trastuzumab pharmacokinetics in early-stage breast cancer, and to study the relationship between exposure and both early clinical response and specific adverse events. Patients and methods: Patients (n = 86) received 6 cycles of docetaxel + trastuzumab. Early tumour response was assessed by determination of the maximum standard uptake value (SUVmax) variation (ΔSUVmax) after 1 cycle using [18F]-fluorodeoxyglucose (FDG) PET. Early poor responders (ΔSUVmax < 70%) also received bevacizumab from cycle 3 to cycle 6. Sources of interindividual variability in pharmacokinetics of both antibodies were studied by population compartment modelling. Exposure as assessed by area under the concentration-versus-time curve (AUC) was compared between responders and non-responders and between patients experiencing specific adverse events or not. Results: A two-compartment model described the pharmacokinetics of both antibodies satisfactorily. Their central volume of distributions (Vc) increased with body surface area and their elimination half-lives were shorter (~14 days) than previously reported (~26–28 days). There was a time-dependent increase in trastuzumab Vc, positively correlated to baseline SUVmax. Bevacizumab elimination rate (k10) was positively correlated with ΔSUVmax measured at the end of the first cycle. Bevacizumab had no significantly influence on trastuzumab pharmacokinetics. No relationship between exposure and clinical response or occurrence of adverse events was found. Conclusion: Tumour uptake as assessed by SUVmax influences the pharmacokinetics of bevacizumab and trastuzumab. In early-stage breast cancer, elimination half-lives of these therapeutic monoclonal antibodies may be shorter than those previously reported in more advanced disease. [ABSTRACT FROM AUTHOR]

To evaluate the efficiency of laser thermocoagulation under computed tomography (CT) guidance in the treatment of osteoid osteoma within a strictly pediatric group. Twenty-five patients aged 4 to 17 years were treated under CT by laser thermocoagulation. The nidus measured on average 10.1 mm. Pain relief was the main item for evaluation of the effectiveness of our treatment. Follow-up ranged from 3 months to 61 months (mean, 26 months). Technical success was achieved in 100%. Thermocoagulation proved to be initially effective in 24 of 25 children (96%) and had a positive long-term effect in 23 of 25 children (92%). We had four minor complications and one severe complication (partial osteonecrosis of the talus). Laser thermocoagualation is an effective treatment for osteoid osteoma in pediatric patients. [ABSTRACT FROM AUTHOR]

Introduction: In the literature, data on the effect of renal impairment on the pharmacokinetics of anticancer drugs are scarce. Here, we report a 68-year-old metastatic osteosarcoma patient with impaired renal function due to prior chemotherapy, who was treated on compassionate use basis with 400 mg/m cetuximab. Material and methods: Pharmacokinetic parameters after the first dose, including dose-normalised AUC from time zero to day 7, clearance, elimination half-life ( t), were estimated using trapezoidal non-compartmental methods and compared to pharmacokinetic data from a study population with normal kidney function. Results: The results showed that the pharmacokinetics of cetuximab in this patient with renal failure was similar to that with adequate renal function. Conclusion: This study suggests that cetuximab can be safely used in cancer patients with renal impairment without dose adjustment. [ABSTRACT FROM AUTHOR]

Background: Preoperative diffusion-weighted MRI (DW-MRI) has been described as an efficient method to differentiate good and poor responders to chemotherapy in osteosarcoma patients. A DW-MRI performed earlier during treatment could be helpful in monitoring chemotherapy. Objective: To assess the accuracy of DW-MRI in evaluating response to chemotherapy in the treatment of osteosarcoma, more specifically at mid-course of treatment. Materials and methods: This study was carried out on a prospective series of adolescents treated for long-bone osteosarcoma. MR examinations were performed at diagnosis (MRI-1), at mid-course of chemotherapy (MRI-2), and immediately before surgery (MRI-3). A DW sequence was performed using diffusion gradients of b0 and b900. The apparent diffusion coefficients (ADC1, ADC2, ADC3, respectively), their differentials (ADC2 − ADC1 and ADC3 − ADC1), and their variation (ADC2 − ADC1/ADC1 and ADC3 − ADC1/ADC1) were calculated for each of these three time points. Results: Fifteen patients were included. Patients with no increase in ADC showed a poor response to chemotherapy on their histology results. At mid-course, the three calculated values were significantly different between good and poor responders. ADC2 − ADC1 enabled us to detect, with 100% specificity, four out of seven of the poor responders. There was no significant difference in the values at MRI-3 between the two groups. Conclusion: DW-MRI performed both at baseline and mid-course of neoadjuvant chemotherapy is an efficient method to predict further histological response of osteosarcoma. This method could be used as an early prognostic factor to monitor preoperative chemotherapy. [ABSTRACT FROM AUTHOR]