Population pharmacokinetics of melphalan in paediatric blood or marrow transplant recipients.

AIM: To develop a population pharmacokinetic model for melphalan in children with malignant diseases and to evaluate limited sampling strategies for melphalan. METHODS: Melphalan concentration data following a single intravenous dose were collected from 59 children with malignant diseases aged between 0.3 and 18 years. The data were split into two sets: the model development dataset (39 children, 571 concentration observations) and the model validation dataset (20 children, 277 concentration observations). Population pharmacokinetic modelling was performed with the NONMEM software. Stepwise multiple linear regression was used to develop a limited sampling model for melphalan. RESULTS: A two-compartment model was fitted to the concentration-vs.-time data. The following covariate population pharmacokinetic models were obtained: (i) Clearance (l h(-1)) = 0.34.WT - 3.17.CPT + 0.0377.GFR, where WT = weight (kg), CPT = prior carboplatin therapy (0 = no, 1 = yes), and GFR = glomerular filtration rate (ml min(-1) 1.73 m(-2)); (ii) Volume of distribution (l) = 1.12 + 0.178.WT. Interpatient variability (coefficient of variation) was 27.3% for clearance and 33.8% for volume of distribution. There was insignificant bias and imprecision between observed and model-predicted melphalan concentrations in the validation dataset. A three-sample limited sampling model was developed which adequately predicted the area under the concentration-time curve (AUC) in the development and validation datasets. CONCLUSIONS: A population pharmacokinetic model for melphalan has been developed and validated and may now be used in conjunction with pharmacodynamic data to develop safe and effective dosing guidelines in children with malignant diseases.

Evaluation of carboplatin pharmacokinetics in pediatric oncology by means of inductively coupled plasma mass spectrometry.

Carboplatin is widely used in pediatric oncology to treat different tumors. Aim of the present study was to assess the potential of sector field inductively coupled plasma mass spectrometry (SF-ICPMS) in evaluating the area under the plasma platinum concentration vs time curve in pediatric patients presenting solid tumors and treated with carboplatin 349-1000 mg m-2. Seventeen patients were enrolled and 23 courses of chemotherapy were evaluated. Plasma was ultrafiltered and free carboplatin was measured in ultrafiltrates as platinum by SF-ICP-MS. Comparison was made between different equations to obtain a target AUC. Limits of detection and of quantification, intra- and inter-day repeatability of the measurements, recovery of the 'free-carboplatin' confirmed SF-ICP-MS as a reliable technique in the quantification of serum platinum in anticancer carboplatin-based therapies.

Cytotoxic effects of some animal and vegetable extracts and some chemicals on liver and colon carcinoma and myosarcoma.

OBJECTIVE: To study, the cytotoxic effects of some biological and chemical agents on G1, S, G2, M and G0 phases of liver and colon carcinomas and myosarcoma cells obtained with chemical carcinogens dimethylbenzanthracene (DMBA) and cadmium chloride. METHODS: Eight rabbit livers, colon carcinoma and myosarcoma cell lines were obtained by injection of DMBA in the Biology Laboratory, of the University of Dumlupinar, Kutahya, Turkey between January 2001 and June 2003. All lines were grown at 37 degrees celsius and 5% carbon dioxide in sterile RPMI-1640 medium with 10% fetal bovine serum after addition of glutamate, penicillin (50 units/ml) and streptomycin (50 ug/ml) (complete medium). Cells were grown on standard tissue culture plastic flasks to 80% confluence and passed by trypsinization. RESULTS: Tortoise (Testudo graeca) shell, sponge (Geodia cydonium), medusa (Aurelia aurita), meat flies (Calliphora erythrocephala) larva, frog (Rana ridibunda) larva and juniper (Juniperus communis) berry extracts killed a large amount of the liver and colon carcinomas and the myosarcoma cells in G2, M and G0 phases (p<0.01). The mistletoe (Viscum album) extract had more effect in only the G0 phase (p<0.05). Genistein, genistin, glycitein, glycitin, daitzein and daitzin have significantly decreased in the cancer cells tests, particularly, genistein and daitzein caused the apoptotic effect in G2, M and G0 phases (p<0.01). Cesium chloride, a mixture of cesium chloride with magnesium chloride had the most effect on tumor cells (p<0.01). AzhexSi, Azhex-AzhepSi, Et-Azhex-AzhepSi, AzhepSi, Hexamine and DL 54 have been inhibited in various levels of the cancer cells (p<0.05, p<0.01). CONCLUSION: This data suggest that some biological extracts and chemicals tested may be useful chemotherapeutic agents to inhibit the growth of cancer cells. This study sheds some light for new anti cancerogenic experiments preventing various cancers on humans.

Postradiation high-grade myofibroblastic sarcoma of the prostate -- a rare entity of prostatic tumors -- responding to liposomal Doxorubicin.

BACKGROUND: Prostatic postradiation sarcoma (PRS) is a very rare malignant disease with a dismal prognosis. Aggressive surgical resection is the most widely used therapy for PRS. Chemotherapy so far has been unsatisfactory, with doxorubicin being the only drug with established activity. Liposomal doxorubicin has been shown to have comparable activity and a more favorable toxicity profile compared with unpegylated doxorubicin. CASE REPORT: A 78-year-old man presented with high-grade myofibroblastic sarcoma 13 years after curatively intended pion irradiation of the prostate with 30 Gy. He was treated with liposomal doxorubicin 40 mg/m(2) every 4-6 weeks up to now with a total dose of 800 mg. Partial remission has been achieved after 17 months of treatment with liposomal doxorubicin. Toxicity is minimal with palmoplantar erythrodysesthesia WHO grade 1, resolving completely after extending treatment intervals to 6 weeks. RESULT: Liposomal doxorubicin led to a sustained tumor stabilization over 17 months in a patient with prostatic postradiation high-grade sarcoma. Postradiation sarcoma (PRS) usually has a dismal prognosis and only very limited therapeutic possibilities. As in sarcomas of different origin, anthracyclines including liposomal doxorubicin seem to have potential antitumor activity in postradiation sarcoma of the prostate.

[Antitumor activity of cytostatics on a newly transplanted tumor in mice, myosarcoma ISM]. / Izuchvane protivotumornata aktivnost na tsitostatitsi vurkhu nov transplantiruem tumor u mishki miosarkom ISM.

The author examined the action of 14 known antitumor preparations on mice BAIB/c with newly transplanted tumour occurred after induction with tetrachlormethane. The tumour myosarcoma ISM showed high sensitivity to cyclophosphamide, administration of which caused complete inhibition of tumour growth and regression of tumours. A comparative high antitumour effect was found after usage of sarcolysine, brunemycine and mitomycine C (over 70% of inhibition). There was a moderately manifested inhibition of the tumour growth (around 50%) after administration of cytostatics degranol, purinetol, 5-fluorouracyl and ftorafur. The substances alexan, rubomycine and 1-(2-chlorethy)-3-cyclohexyl-1-nitrosourea were without effect on myosarcom ISM. The obtained data showed that then tumour well differentiated substances in accordance with their action. It is a prorer model for thorough investigation of antitumour substances.