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At least 973 records · Page 54Linked to original sources
PubMed1995

Interferon-alpha does not improve the antineoplastic efficacy of high-dose infusional 5-fluorouracil plus folinic acid in advanced colorectal cancer. First results of a randomized multicenter study by the Association of Medical Oncology of the German Cancer Society (AIO).

BACKGROUND: High-dose 5-FU given weekly as a 24-h infusion in combination with folinic acid (FA) has been associated with low toxicity and a high response rate. Interferon-alpha (IFN) either alone or in combination with FA has also improved treatment results by modulating 5-FU activity. We therefore initiated a randomized multicenter trial comparing the ability of FA or IFN to modulate infusional 5-FU. The statistical design using a sequential analysis allows us to report on the comparison of 5-FU/FA vs. 5-FU/FA/IFN while randomization of patients into 5-FU/FA vs. 5 FU/IFN continues. METHODS: Chemotherapy-naive patients with advanced progressive colorectal cancer and measurable metastatic lesions were randomized to receive 5-FU 2600 mg/m2 i.v. as a 24-h infusion, combined with either FA 500 mg/m2 as a 2-h infusion (A), or IFN 3 x 10(6) U s.c. 3 x/week (B), or the combination of FA plus IFN as in arms A and B (C). Treatment arms were repeated weekly for 6 weeks followed by a 2-week rest period. These 8-week cycles were administered until tumor progression. Because of the occurrence of 2 toxic deaths among the first 17 patients treated in arm C, 5-FU was reduced to 2000 mg/m2 for all patients in arm C. Sequential analysis according to Whitehead for objective response was planned with alpha = 0.05/3 and a power of 80% (beta = 0.2) to detect a difference of > or = 25% (delta = 0.25) or equivalence of response rates. For pairwise comparison of treatment arms a minimum of 30 patients per arm and a maximum of 90 patients per arm were expected in case of equivalence or difference. RESULTS: An interim analysis was performed after the first 93 of 149 randomized patients were evaluable for response and toxicity (A 31 pts, B 33 pts, C 29 pts). Despite the 5-FU dose reduction in arm C, 28% of patients experienced grade 3/4 toxicity (CTC) including diarrhea, mucositis and handfoot syndrome compared to 16% in arm A and 12% in arm B (not significant). No treatment related toxic death occurred in arms A or B, but 3 patients (10%) in arm C died of diarrhea and septicemia. Among patients treated with 5-FU/FA objective tumor response occurred in 12/31 patients (39%) (21%-56%, 95% confidence interval) (3 CR, 9 PR), no change in 13/31 (42%) and PD in 6/31 (19%) patients. Eleven of 29 patients (38%) (20%-56%, 95% confidence interval) receiving 5-FU/FA/IFN achieved complete (3 patients) or partial (8 patients) remissions, 10/29 patients (34%) had stable disease and 8/29 patients (28%) tumor progression. According to the sequential analysis the rates of objective responses observed in patients treated with 5-FU/FA or 5-FU/FA/IFN were equivalent. CONCLUSION: This interim analysis allows the conclusion that infusional 5-FU plus FA/IFN is no more active than infusional 5-FU plus FA alone. However, 5-FU/FA/IFN despite 5-FU dose reduction was associated with unacceptably high toxicity, including 10% deaths. Therefore, further investigation of this regimen is not justified. The study is continued with the comparison of 5-FU/FA vs. 5-FU/IFN.

Adult↗
PubMed2005

Survey of dental radiological practice in Turkey.

OBJECTIVES: The aim of this study was to determine the dentist's knowledge about dose reduction techniques, radiographic equipment and quality of dental radiographic service in general dental practice in Turkey. METHODS: The survey was performed on 636 dentists who attended the 11th International Congress organized by the Turkish Dental Association. Information on the demographic characteristics of the dentists, radiographic equipment, techniques and processing they used and radiation protection was obtained with a 32 point questionnaire. RESULTS: The respondents' knowledge concerning the technical details of their equipment was limited, with 512 (86.9%) not knowing the kilovoltage peak (kVp) of their machine. Only 34 (5.5%) respondents reported having rectangular collimators. The dentists had little knowledge about the speed of film they used. D-speed film was the most preferred one with 21.6%. Fifty-eight (10.2%) dentists used E-speed film and the F-speed film was used only by 13 (2.3%) dentists. The most preferred technique (62%) for periapical radiography was the bisecting angle technique. Four hundred and eighty five (82.5%) of the dentists reported that they took the radiographs by themselves. CONCLUSIONS: In the present study, the results indicate that for minimizing any unnecessary radiation, attempts should be made to improve dentists' knowledge about radiation dose reduction techniques.

Adult↗
PubMed2006

Co-administration of ketoconazole and tacrolimus therapy: a transplanted rat model.

BACKGROUND/AIM: The aim of this work is to study the effect of addition of ketoconazole to experimental kidney transplanted rat treated with tacrolimus and precludes the percentage of tacrolimus dose reduction. MATERIAL AND METHODS: The material of this work included 60 male Sprague Dawely rats subjected to renal allotransplantation. They were equally divided into five groups: Group I: served as control group, Group II: received FK506 3.2 mg/kg/bw, Group III: received FK506 2 mg/kg/bw, Group IV: received FK506 1 mg/kg/bw, Group V: received FK506 1 mg/kg/bw plus ketoconazole 20 mg/kg/day. FK506 trough level and laboratory investigations were determined at 0, 3, 7, 10, 14, and 27 days post-transplantation. RESULTS: In all groups loss of body weight was observed at day 27 after treatment compared to that before transplantation. Serum creatinine significantly increased at day 27 compared to the basal level in groups treated with 1.0 mg and 3.2 mg FK506 (1.80+/-0.50 vs. 0.39+/-0.06 P=0.001) and (1.03+/-0.26 vs. 0.50+/-0.07 P=0.001) respectively. While for 2.0 mg or 1.0 mg plus keto groups, no significant differences in serum creatinine levels over time (0.56+/-0.22 vs. 0.44+/-0.10 P=0.106) and (0.55+/-0.30 vs. 0.42+/-0.08 P=0.160) were observed. CONCLUSION: Concomitant administration of ketoconazole and FK506 is safe and results in increase blood trough level concentration of FK506 with 50% dose reduction in transplanted rat model.

Animals↗
PubMed2001

Are medical oncologists biased in their treatment of the large woman with breast cancer?

PURPOSE: Obesity and breast cancer are common conditions that often coexist. Concerns of relative overdosing of chemotherapy in the large cancer patient have led clinicians to apply empiric dose reductions, 'cap' the body surface area (BSA) at 2 m2, or use ideal rather than actual body weight to calculate BSA. There are no data supporting or refuting these practices and their prevalence is unknown. We sought to determine the distribution of body size and prevalence of obesity in the breast cancer population of our cancer centre, and to determine clinician chemotherapy dosing practices in the era of modern adjuvant chemotherapy. PATIENTS AND METHODS: Women with invasive breast cancer receiving systemic therapy at our institution between 1980 and 1998 were identified and their recorded height and weight were used to calculate BSA and body mass index (BMI). We reviewed the first cycle adjuvant chemotherapy dosing practices from 1990-1998. The ideal dose of chemotherapy was calculated based on calculated BSA, and then contrasted with the actual dose received at cycle one. Discrepancies were recorded and categorized, using the largest single drug reduction if more than one drug was reduced. RESULTS: Mean BMI in the systemic therapy population was 26.4 +/- 5.3 kg/m2, 54% were overweight, 2% severely obese and 18% moderately so. Their mean BSA was 1.7 +/- 0.2 m2 and only 5% had a BSA > or = 2 m2. In the adjuvant chemotherapy subgroup, most patients received > or = 85% of their ideal dose. The mean dose reduction was 5.3 +/- 11.3% versus 9.9 +/- 11.3% in the BSA < 2 and > or = 2 m2 groups, respectively (p = 0.02), and 4.3 +/- 8.2% versus 6.7 +/- 13.1% in the BMI < 25 and > or = 25 kg/m2 groups, respectively (p = 0.008). While only 24% of chemotherapy dose reductions of > or = 15% were in the BSA > or = 2 m2 group, 76% were in the BMI > or = 25 kg/m2 group. CONCLUSIONS: Obesity is prevalent in this breast cancer population. BSA is not a sensitive index of large body size. We consistently detected more frequent empiric dose reductions at cycle one of adjuvant chemotherapy, with reductions of greater magnitude in the largest women (BSA > or = 2 m2) and those who were overweight (BMI > or = 25 kg/m2).

Adult↗
PubMed1999

Dose-dependent reduction of apoptosis in nutrient-limited cultures of NS/0 myeloma cells transfected with the E1B-19K adenoviral gene.

It is now well documented that apoptosis represents the prevalent mode of death in lymphoid cultures and occurs spontaneously in late-exponential phase of batch cultures following nutrient exhaustion. In an attempt to enhance the cell survival of these cell lines, we have initially engineered nonproducing NS/0 myeloma cells with a vector expressing the adenoviral E1B-19K protein. NS/0 cells transfected with E1B-19K were found to be more resistant to apoptosis occurring in the late phase of batch culture and under stressful conditions such as cultivation in glutamine-free medium or following heat shock. In this study, we have characterised a number of NS/0 subclones constitutively expressing different levels of E1B-19K, as well as several subclones in which the expression of E1B-19K was regulated by a tetracycline-controllable gene switch. We have found that a threshold E1B-19K level was required in order to achieve protection against apoptosis. The extent of resistance against cell death induced by nutrient deprivation in glutamine-free medium and in the late phase of batch cultures correlated with the level of E1B-19K expression up to an optimal level where further increases in E1B-19K levels did not result in significant additional protection. To assess the effects of E1B-19K on antibody productivity, an apoptosis-resistant NS/0 clone was then transfected with a chimeric antibody construct. Despite their improved viability, the antibody productivity of E1B-19K clones in batch culture was not significantly improved. Moreover, while the use of E1B-19K considerably delayed cell death, cells eventually died by apoptosis. Surprisingly, E1B-19K had no beneficial effect on the efficiency of fusion of NS/0 myelomas and splenocytes for the generation of hybridoma cells. Furthermore, the resulting hybridomas, although expressing E1B-19K at levels comparable to the myeloma parent, were no longer resistant to apoptosis. This indicates that the ability of E1B-19K to prevent apoptosis is not only dose-dependent but also seems to be cell-type dependent.

Adenovirus E1B Proteins↗
PubMed2006

Early experience with Levosimendan in children with ventricular dysfunction.

OBJECTIVE: To describe our preliminary experience with Levosimendan, a new calcium-sensitizing agent in critically unwell infants and children with severe heart failure. DESIGN: Retrospective cohort analysis. SETTING: Pediatric intensive care unit. PATIENTS: Fifteen children aged 7 days to 18 yrs (median age 38 months) with severe myocardial dysfunction secondary to end-stage heart failure, or acute heart failure, who were inotrope-dependent (requiring at least one catecholamine). INTERVENTIONS: A single dose (bolus and intravenous infusion over 24-48 hrs) of Levosimendan was given under continuous hemodynamic monitoring in our intensive care unit. Eleven children received a single dose, three children received two doses, and one child received four doses. Echocardiographic assessments of ventricular function were made before and 3-5 days after Levosimendan infusion. MEASUREMENTS AND MAIN RESULTS: Heart rate, systolic pressure, diastolic pressure, mean blood pressure, and central venous pressure were unchanged during and after Levosimendan. Levosimendan allowed for discontinuation of catecholamines in ten patients and a dose reduction in three. The dose of dobutamine was reduced from 6.4 microg/kg/min pre-Levosimendan to 1.8 microg/kg/min on day 5 (p < .01). Ejection fraction for the group as a whole improved from 29.8% to 40.5% (p = .015); this did not increase significantly in patients with end-stage heart failure but increased by 63% in the children with acute heart failure. CONCLUSIONS: Levosimendan can be safely administered to infants and children with severe heart failure. Levosimendan allowed for substantial reduction in catecholamine infusions in children with end-stage or acute heart failure and also produced an objective improvement in myocardial performance in children with acute heart failure.

Adolescent↗
PubMed1995

Isoflurane and sevoflurane produce a dose-dependent reduction in the shivering threshold in rabbits.

All general anesthetics markedly impair thermoregulatory responses; nonetheless, sufficient hyperthermia or hypothermia will trigger most protective reflexes. Shivering, however, remains an exception among thermo-regulatory responses: it is common during postanesthetic recovery, but is rare at typical anesthetic concentrations. This observation suggests that general anesthesia impairs shivering far more than other thermoregulatory defenses. Accordingly, we tested the hypothesis that low concentrations of isoflurane and sevoflurane would virtually obliterate shivering. Japanese white rabbits were anesthetized with isoflurane or sevoflurane at end-tidal concentrations of 0.2, 0.3, and 0.4 minimum alveolar anesthetic concentration (MAC) (n = 6 in each group); the normal core temperature for these rabbits is approximately 39 degrees C. Core temperatures were subsequently reduced by a water-perfused thermode positioned in the colon. The core temperature triggering shivering identified the threshold for this response. Five of the six rabbits given 0.2 MAC isoflurane shivered at a mean core temperature of 36.3 +/- 0.3 degrees C (mean +/- SD), and one rabbit failed to shiver at a minimum core temperature of 35.0 degrees C. Four of the six rabbits given 0.3 MAC isoflurane shivered at a mean core temperature of 36.2 +/- 0.6 degrees C, and two of these rabbits failed to shiver at a minimum core temperature of 35.0 degrees C. However, no rabbit given 0.4 MAC isoflurane shivered, even at minimum core temperatures of 35.0 degrees C. All of the rabbits given 0.2 MAC sevoflurane shivered at a mean core temperature of 36.6 +/- 0.7 degrees C.(ABSTRACT TRUNCATED AT 250 WORDS)

Anesthetics↗
PubMed1999

Phase II trial of vinorelbine in recurrent and progressive epithelial ovarian cancer.

OBJECTIVE: A phase II, multicenter trial was conducted to define the efficacy and safety of vinorelbine (Navelbine (vinorelbine tartrate) injection, NVB) in the treatment of advanced epithelial ovarian cancer (EOC). METHODS: Patients with persistent or recurrent EOC who had received one prior platinum-based chemotherapy regimen were eligible. NVB was administered at 30 mg/m2 as a weekly outpatient intravenous infusion. RESULTS: Using an intent-to-treat analysis of the 38 patients who received at least one dose, 11(29%, 95% confidence limits 15-46%) objective responses (4 complete, 7 partial) were observed. The median duration of response was 19 weeks. For all 38 patients, the median time to treatment failure and median survival were 12 and 60 weeks, respectively. Four of the 12 patients with platinum-resistant disease responded, while 7 of the 24 patients with platinum-sensitive disease responded. Toxicity was evaluable in all 38 patients. During course 1, 15 patients required dose reduction and 21 required dose delays. Grade 3-4 granulocytopenia occurred in 23 (62%) of 37 reporting patients. Grade 3-4 anemia and thrombocytopenia occurred in 16 and 5%, respectively. The most common nonhematologic toxicities were nausea (grade 3 or less, in 34%), constipation (grade 3 or less, in 29%), and asthenia (grade 2 or less, in 24%). No life-threatening adverse effects were reported. CONCLUSIONS: NVB is an effective, palliative agent for women with recurrent EOC. Dose-limiting granulocytopenia is substantial, yet manageable.

Adult↗
PubMed1999

Is age a barrier to the aggressive treatment of ovarian cancer with paclitaxel and carboplatin?

OBJECTIVE: The objective of this study was to determine whether the toxicities associated with chemotherapy are age related in women treated for ovarian cancer. METHODS: Patients with stage II-IV epithelial ovarian cancer underwent cytoreductive surgery. Adjunctive therapy was given to each patient consisting of intravenous (IV) paclitaxel 175 mg/m(2) over 3 h with a subsequent 30-min IV infusion of carboplatin. Carboplatin dose was calculated to achieve a targeted area under the curve (AUC) of 5.0-7.5. Treatment was repeated at 21- to 28-day intervals for six cycles. Toxicities were graded after each dose of chemotherapy. Results were analyzed using the Wilcoxon rank sum test and log likelihood ratio to compare toxicities in women age <60 years old to women >/=60 years old. RESULTS: Fifty-three women, 22 of whom were >/=60 years old, were treated with 309 cycles of chemotherapy. Forty-eight patients (92%) completed all six cycles. AUC dosing of carboplatin was equivalent for both groups. Carboplatin dose reduction occurred in 75% of patients for grade 4 neutropenia or thrombocytopenia. No patient required a reduction in the paclitaxel dose. Neutropenia was less frequent in women >/=60 years old than in women <60 years old (P = 0.02). There was no difference between women <60 years old and women >/=60 years old in the incidence of anemia, thrombocytopenia, or the use of growth factors. A 68% complete clinical response rate was observed in women >/=60 years old compared to a 74% complete response rate for women under age 60 (P = 0.22). CONCLUSION: Age is not a barrier to the aggressive treatment of ovarian cancer with this regimen of paclitaxel and carboplatin.

Adult↗
PubMed1996

Dose-time response in mouse skin tumor induction by 7, 12-dimethylbenz[a]anthracene and 12-O-tetradecanoyl-phorbol-13-acetate.

The question was addressed whether the dose-response relationship derived from a carcinogenicity study can be used for mechanistic interpretation and to what extent the shape of the curve is dependent on the duration of the bioassay and the time of analysis. The mouse skin tumor model was used. It allows recording of the time of tumor appearance without interim sacrifice. Groups of 16 female NMRI mice were treated twice weekly by dermal administration with combinations of (a) 2.5 nmol 12-O-tetradecanoyl-phorbol-13-acetate (TPA) plus 0, 0.3, 1, 3, or 10 nmol 7,12-dimethylbenz[a]anthracene (DMBA) or with (b) 2.5 nmol DMBA plus 0, 0.1, 0.3, 1, 3, or 10 nmol TPA. The appearance of the first papilloma was recorded for each animal and the cumulative incidence data were analyzed in two ways: (i) With the usual dose-prevalence representation at a fixed time point, the dose response for TPA was sigmoidal, while it was linear-superlinear for DMBA. This was observed at all time points, indicating that the dose-response information may be used for a distinction between DNA-reactive and tumor-promoting mechanisms of action. (ii) When time-to-tumor and loss of tumor-free lifetime was analyzed as a function of dose, there was again a marked difference between DMBA and TPA. The tumor-free lifetime increased with each step of dose reduction but the slope was about four times larger for TPA compared with that for DMBA. Further reduction of the TPA dose could result in a situation in which the natural life span sets a limit to an observable effect. Under the conditions of this bioassay for mouse skin papilloma induction by a combination treatment with DMBA plus TPA, the findings support the idea of a no-effect low-dose threshold for the tumor-promoting agent.

9,10-Dimethyl-1,2-benzanthracene↗
PubMed1979

Reduction of dose in pelvic examinations of infants using modern X-ray techniques.

A simple dose-saving procedure for the diagnosis of congenital hip dysplasia employing a diaphragm in near-focus position is presented. Doses to the skin and the gonads are measured with a phantom, comparing the new and other techniques. With optimal techniques the skin dose is smaller than 2 mR and the gonadal doses lie around 0.1 mR for both male and female patients.

Age Factors↗
PubMed1995

Influence of age, renal and liver impairment on the pharmacokinetics of risperidone in man.

The pharmacokinetics of the antipsychotic agent risperidone were investigated in healthy young and elderly subjects, cirrhotic patients and patients with moderate and severe renal insufficiency. In a comparative trial, a single oral 1-mg dose was administered to fasting subjects. Plasma and urine concentrations of the parent compound risperidone and the active moiety (i.e. risperidone plus 9-hydroxy-risperidone) were measured by radioimmunoassays. No or only small changes in plasma protein binding were observed in hepatic and renal disease, whereas the protein binding was not influenced by aging. The inter-individual variability in plasma concentrations of the active moiety was much less than the variability in plasma concentrations of risperidone. Three out of six subjects, behaving like poor metabolizers, were on medication (thiethylperazine, amitriptyline, metoprolol) that may inhibit risperidone metabolism by CYP2D6 (debrisoquine 4-hydroxylase). The pharmacokinetics of risperidone in elderly and cirrhotic patients were comparable to those in young subjects, whereas total oral clearance was reduced in renal disease patients. The elimination rate and clearance of 9-hydroxy-risperidone was reduced in elderly and renal disease patients because of a diminished creatinine clearance. The CL(oral) of the active moiety, which is primarily 9-hydroxy-risperidone, was reduced by about 30% in the elderly and by about 50% in renal disease patients. In addition, the t1/2 of the active moiety was prolonged (19 h in young subjects versus about 25 h in elderly and renal disease patients). Based upon the pharmacokinetics of the active moiety, a dose reduction and a cautious dose titration is advised in the elderly and in patients with renal disease. In cirrhotic patients, the single-dose pharmacokinetics were comparable to those in healthy young subjects.

Adult↗
PubMed2006

Radiation protection in radionuclide therapies with (90)Y-conjugates: risks and safety.

PURPOSE: The widespread interest in (90)Y internal radionuclide treatments has drawn attention to the issue of radiation protection for staff. Our aim in this study was to identify personnel at risk and to validate the protection devices used. METHODS: (90)Y-MoAb (Zevalin, 15 cases, 1.1 GBq/patient) and (90)Y-peptide ((90)Y-DOTATOC) systemic (i.v., 50 cases, 3.0 GBq/patient) and locoregional (l.r., 50 cases, 0.4 GBq/patient) treatments were considered. Radiolabelling was carried out in a dedicated hot cell. Tele-tongs, shielded (PMMA: polymethylmethacrylate) syringes/vials and an automatic dose fractionating system were used. Operators wore anti-X-ray and anti-contamination gloves, with TLD dosimeters placed over the fingertips. For i.v. administration, activity was administered by a dedicated system; for l.r. administration, during activity infusion in the brain cavity, tongs were used and TLDs were placed over the fingertips. The air kerma-rate was measured around the patients. RESULTS: The use of devices provided a 75% dose reduction, with mean fingertip doses of 2.9 mGy (i.v. MoAbs), 0.6 mGy (i.v. peptides)/radiolabelling procedure and 0.5 mGy/l.r. administration. The mean effective dose to personnel was 5 microSv/patient. The air kerma-rate around the patients administered i.v. (90)Y-peptides were 3.5 (1 h) and 1.0 (48 h) microGy/h at 1 m. Patient hospitalisation of 6 h (l.r.)/48 h (i.v.) guaranteed that the recommended limits of 3 mSv/year to family members and 0.3 mSv/year to the general population (Council Directive 97/43/Euratom) were respected. CONCLUSIONS: When specific procedures are adopted, a substantial improvement in (90)Y manipulation is attainable, reducing doses and increasing safety. For the widespread clinical use of (90)Y-conjugates, a completely automatic labelling procedure is desirable.

Italy↗
PubMed2006

Neutropenic event risk and impaired chemotherapy delivery in six European audits of breast cancer treatment.

GOALS OF WORK: The aims of this study were to assess chemotherapy treatment characteristics, neutropenic event (NE) occurrence and related risk factors in breast cancer patients in Western Europe. MATERIALS AND METHODS: Six retrospective audits of breast cancer chemotherapy were combined into a dataset of 2,860 individuals. NEs were defined as neutropenia-related hospitalisation, dose reduction > or = 15% or dose delay > or = 7 days. Summation dose intensity (SDI) was calculated to compare different types of chemotherapy regimens on a single scale. Risk factors of NE occurrence and of low relative dose intensity (RDI) < or = 85% were identified by multiple logistic regression. MAIN RESULTS: Patient populations were comparable between audits. Until 1998, cyclophosphamide, methotrexate and fluorouracil regimens were most frequently used, but thereafter, anthracycline-based regimens were most common. NEs occurred in 20% of the patients and low RDI in 16%. NE occurrence predicted low RDI and was associated with higher age, bigger body surface area, lower body mass index, regimen type, more chemotherapy cycles planned, normal to high SDI, concomitant radiotherapy and year of treatment. First cycle NE occurrence predicted NEs from cycle 2 onwards. A risk score using age, SDI, number of planned chemotherapy cycles and concomitant radiotherapy differentiated patients with increasing NE risk (9-37%). An alternative score version not using concomitant radiotherapy performed moderately less well. CONCLUSIONS: NEs occurred frequently in this combined dataset and they affected treatment delivery. Identifying patients at high NE risk enables targeted prophylaxis and may avoid dose limitations.

Adult↗
PubMed1989

A filter for use in lateral cephalography.

A new filter was devised for density compensation and absorbed-dose reduction in cephalometric radiographs. It is composed of a rare earth screen that plays a role in depicting soft tissue shadows and cephalometric points. The greatest reduction of the absorbed dose was about one seventh at the tube side of the thyroid gland when it was included in the direct x-ray beam. Smaller collimation was the most important factor in reducing the absorbed dose.

Aluminum↗
PubMed1991

Phase II study with mitomycin, ifosfamide and carboplatin in inoperable non-small cell lung cancer.

In a phase II study of non-small cell lung cancer a new chemotherapy combination of mitomycin 6 mg/m2 intravenously on day 1, carboplatin 400 mg/m2 intravenously on day 1 and ifosfamide with mesna 5 g/m2 intravenously over 24 hours on day 1 was evaluated. A maximum of four chemotherapy cycles was given at intervals of 4 weeks to 34 patients with progressive, inoperable disease. 1 complete and 10 partial remissions were documented, the overall response rate being 32.4%. In a further 13 patients (38.2%) the previously progressing tumours remained stable for at least 6 weeks. The median time to progression for responding patients was 184 days. The median survival time for the whole group has not yet been reached at 293 days. A considerable but easily manageable myelosuppression was the principal toxicity despite a "no dose reduction" policy. Indeed, the dose intensity of the chemotherapy actually given was extremely close (97%) to that intended on protocol. In conclusion, the regimen is active in patients with advanced non-small cell lung cancer but requires regular haematological monitoring to prevent morbidity resulting from myelotoxicity.

Aged↗
PubMedDate not supplied

Reduction of dosing frequency of carbamazepine with a slow-release preparation.

The occurrence of side effects and epileptic seizures and the pharmacokinetics of carbamazepine (CBZ) and carbamazepine-10,11-epoxide were studied using a slow-release CBZ preparation, Neurotol slow, and a conventional CBZ preparation, Tegretol. The study was an open, randomized cross-over trial, with a 2 week study period for each preparation. Tegretol was given 3 times and Neurotol slow twice a day. The earlier CBZ dose was kept unchanged. The initial sample consisted of 24 adult epileptic patients receiving CBZ treatment of whom 20 patients were evaluable. The fluctuation in serum CBZ concentrations did not differ significantly between the 2 treatment periods, even though the interdose interval of Neurotol slow was 4 h longer than that of Tegretol. The switch-over from conventional CBZ to the slow-release formulation did not seem to alter the efficacy and side effects of CBZ. By using Neurotol slow instead of a conventional CBZ preparation, Tegretol, it is evidently possible to reduce the dosing frequency from 3 times a day to twice daily administrations.

Adolescent↗