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PubMed2000

Lumbar spine radiology: analysis of the posteroanterior projection.

The use of the posteroanterior (PA) technique as a means of dose reduction has been used effectively in radiology departments for chest and abdominal examinations. The aim of this investigation was to establish if the PA lumbar spine projection offers any advantages over the traditional anteroposterior (AP) view in terms of radiation dose and image quality. The contribution of tissue displacement to any dose reduction was also evaluated. The first part of the study involved the use of an anthropological phantom where entrance surface and an internal dose were measured for both the PA and AP projections. Entrance surface doses for both projections were then measured on randomly allocated female patients. Resultant image quality was assessed using CEC quality criteria. Anterior to posterior patient diameter was also recorded. The results demonstrated that with the PA compared with the AP projection, reductions of 38.6% (p = 0.016) and 38.9% (p = 0.02) in patient entrance surface dose and internal phantom dose, respectively. No significant differences in image quality were noted between the two projections. Patient diameter decreased by 1.8 cm with the PA view. The authors conclude that tissue displacement is the main factor for the patient dose reduction and recommend employment of the PA procedure for routine lumbar spine examinations.

Humans↗

PubMed1992

Phase II trial of cisplatin and alpha-interferon in advanced malignant melanoma.

PURPOSE: To evaluate the antitumor activity of combination cisplatin (CDDP) and alpha-interferon (alpha-IFN) in advanced, measurable metastatic melanoma. PATIENTS AND METHODS: Adult patients with metastatic melanoma were required to have bidimensionally measurable lesions and a Karnofsky performance status > or = 60%. Serum creatinine < or = to 1.5 mg/dL, creatinine clearance > or = 60 mL/min, adequate organ and bone marrow function, and radiologic proof of the absence of brain metastases were required. CDDP 40 mg/m2 intravenously (IV) on day 1 and day 8, and alpha-IFN 3 million units/m2 subcutaneously on days 1 to 5 and 8 to 12 were administered every 3 to 4 weeks. RESULTS: Forty-two patients were entered onto this phase II trial and were assessable for response and toxicity. Three patients achieved complete responses (CRs) that lasted 31+, 5, and 8+ months. Seven patients had partial responses (PRs) and a median response duration of 4.4 months. The overall objective response rate was 24% (95% confidence interval, 12% to 39%). Toxicities were mild. Only 11% of the courses required dose reduction of alpha-IFN, and three of 128 courses required CDDP dose reduction for reversible nephrotoxicity. CONCLUSION: The combination of moderate-dose CDDP and alpha-IFN as administered in this schedule is well tolerated and possesses encouraging activity in metastatic melanoma.

Adult↗

PubMedDate not supplied

Fluoroscopy: patient radiation exposure issues.

Fluoroscopic procedures (particularly prolonged interventional procedures) may involve high patient radiation doses. The radiation dose depends on the type of examination, the patient size, the equipment, the technique, and many other factors. The performance of the fluoroscopy system with respect to radiation dose is best characterized by the receptor entrance exposure and skin entrance exposure rates, which should be assessed at regular intervals. Management of patient exposure involves not only measurement of these rates but also clinical monitoring of patient doses. Direct monitoring of patient skin doses during procedures is highly desirable, but current methods still have serious limitations. Skin doses may be reduced by using intermittent exposures, grid removal, last image hold, dose spreading, beam filtration, pulsed fluoroscopy, and other dose reduction techniques. Proper training of fluoroscopic operators, understanding the factors that influence radiation dose, and use of various dose reduction techniques may allow effective management of patient dose.

Fluoroscopy↗

PubMed2003

Filgrastim support during combination chemotherapy using cisplatin, doxorubicin, and cyclophosphamide to treat advanced or recurrent endometrial cancer: a clinical study and literature review.

In a private practice setting, 16 patients with advanced or recurrent endometrial carcinoma received cisplatinum 50 mg/m2, doxorubicin 50 mg/m2, and cyclophosphamide 750 mg/m2 every three weeks. Growth factor support using filgrastim was initiated on the first cycle of therapy and each subsequent cycle. Sixteen patients were entered into the study with 13 being evaluable. No patient had previously received chemotherapy. The overall response rate was 54% with two complete responses (15%) and five partial responses (38%). Stable disease was seen in 46% of patients. Progression-free survival was observed to be a median of 8.5 months for a complete response, a median of 8.5 months for a partial response and a median of 7 months for stable disease. Fifteen percent of the patients and 3% of all chemotherapy cycles had febrile neutropenic events. There were no deaths due to myelotoxicity. Only one patient required a dose reduction due to neutropenia. Four of the 13 patients required dose reductions due to previous nadir thrombocytopenia. Grade 4 granulocytopenia occurred in 28% of treatment cycles and grade 3 granulocytopenia occurred in 12% of treatment cycles. The use of filgrastim (G-CSF) allowed patients to stay on therapy for an average of seven treatments. Neutropenia was not the dose-limiting toxicity from this dose-intense regimen.

Adenocarcinoma↗

PubMed2004

A review of factors affecting patient doses for barium enemas and meals.

A study of patient doses for barium enema and meal examinations has been carried out for hospitals in the West of Scotland to assess the impact of dose reduction facilities on new X-ray equipment. Dose-area product (DAP) information has been collected on examinations for groups of patients at 20 hospitals and results reviewed together with data on equipment performance measurements. Median DAPs for barium enemas and meals were 15.7 Gy cm(2) and 4.8 Gy cm(2), respectively, and effective doses estimated from the results are 3.5+/-0.7 mSv and 1.5+/-0.5 mSv, respectively. These doses are lower than those reported in earlier studies and in previous surveys in the West of Scotland. The reduction in dose is linked primarily to the low dose facilities available on newer X-ray equipment, such as low dose pulsed fluoroscopy, digital imaging facilities and use of copper filtration. Use of the image intensifier for decubitus images on C-arm units employed for barium enemas also gives a significantly lower dose. Equipment with copper filtration had the lowest doses. The reduction in effective dose will be significantly less than the reduction in DAP for units in which a copper filter is included and the adoption of lower diagnostic reference levels is proposed for units with this facility. It is important that the operators are aware of the low dose imaging options on their equipment in order that techniques can be fully optimized.

Barium Sulfate↗

PubMed1999

Phase I study of escalating doses of edatrexate in combination with paclitaxel in patients with metastatic breast cancer.

Motivated by the observation of preclinical synergy, a Phase I dose escalation study of edatrexate in combination with a 3-h paclitaxel infusion was performed in patients with advanced breast cancer to determine the maximum tolerated dose (MTD) of edatrexate and the toxicities associated with this combination and to report preliminary observations of efficacy with this novel combination. Thirty-six patients were enrolled in this Phase I trial. Thirty-five eligible patients were treated every 21 days in cohorts of at least three patients and were assessable for toxicity. One patient was ineligible due to hyperbilirubinemia. Stepwise dose escalations of edatrexate were administered until grade >3 nonhematological dose-limiting toxicities were reported. The initial dose level of edatrexate was 180 mg/m2; subsequent cohorts were treated with escalating doses of edatrexate (210, 240, 270, 300, 350, and 400 mg/m2). Edatrexate was administered by i.v. infusion over 1 h. Paclitaxel was administered 24 h later at a fixed dose of 175 mg/m2 as a 3-h infusion with standard dexamethasone, diphenhydramine, and cimetidine premedication. The MTD of edatrexate was reached at the 350 mg/m2 level in this study. Grade 3 diarrhea was seen in one patient at the 300 and 400 mg/m2 dose levels, requiring dose reductions. Two patients experienced grade 4 stomatitis at the 400 mg/m2 dose level and also required dose reduction, establishing the MTD as 350 mg/m2. Grade 3 nausea and vomiting were noted in two of three patients at the highest dose level. Of 35 patients, 4 patients reported grade 3 myalgias and 1 patient reported grade 3 neurosensory complaints, which were seen mostly at the 350 and 400 mg/m2 dose levels; however, 1 patient reported grade 3 myalgias at 180 mg/m2. No cumulative neurotoxicity was observed, and no patient experienced an allergic reaction to paclitaxel. In 23 patients with bidimensionally measurable disease, there were four complete (17%) and seven partial responses, with an overall response rate of 48% (95% confidence interval, 27-69%). All of the responses were seen in patients who had not received prior chemotherapy for stage IV disease. The median duration of response was not assessable because many responding patients went on to receive high-dose chemotherapy treatment with stem cell support. The combination of edatrexate and paclitaxel for treatment of metastatic breast cancer is a feasible and safe regimen. The MTD of edatrexate was 350 mg/m2 when combined with a 3-h infusion of paclitaxel (175 mg/m2) given 24 h later. Activity was noted even among patients who had relapsed shortly after receiving methotrexate- and/or doxorubicin-containing adjuvant regimens. Additional studies evaluating the sequences and dosing schema for this combination are warranted to improve the response proportion and define the duration of the response.

Adult↗

PubMed1999

Vancomycin clearance during continuous venovenous haemofiltration in critically ill patients.

OBJECTIVE: To study the pharmacokinetics of vancoymcin in critically ill patients with acute renal failure treated with continuous venovenous haemofiltration (CVVHF). DESIGN: Open-label study. SETTING: Hospital pharmacy centre and medical intensive care unit of the University Medical Centre Utrecht. MATERIALS AND METHODS: In a laboratory setting, the sieving coefficient (s) of vancomycin by polyacrilonitrile (PAN) haemofilters of different surface areas was studied. In one patient, the pharmacokinetics of vancomycin were studied following a single dose of vancomycin. Another patient was treated with a vancomycin dosing regimen based on data from the literature, but high trough concentrations made dose reduction necessary after 24 h of withholding therapy. After two doses of 250 mg, serum and ultrafiltrate samples were collected for pharmacokinetic evaluation. INTERVENTIONS++: CVVHF with the following operational characteristics: blood flow 200 ml/min, ultrafiltrate flow 25 ml/min, postdilution, PAN 06 hollow fibre haemofilter. MEASUREMENTS AND RESULTS: The average sieving coefficient in vitro was 0.73 +/- 0.06, 0.86 +/- 0.11, and 0.80 +/- 0.06 for the PAN 03, 06, and 10 haemofilters, respectively. Changes in the sieving coefficient by increasing the ultrafiltration rate were not clinically significant. The first patient was given a single dose of vancomycin, 1000 mg by intravenous infusion. The following pharmacokinetic data were obtained: apparent volume of distribution (Vd) 55.8 l, terminal half-life time (t(1/2 term)) 15.4 h, total clearance (Cl(tot)) 2.5 l/h, CVVHF clearance (CL(CVVHF, form 1)) 1.4 l/h, and body clearance (Cl(body)) 1.1 l/h. The average sieving coefficient during the study period was 0.89 +/- 0.03. In the second patient, the pharmacokinetics of vancomycin were studied following dose reduction: Vd 41.7 l, (1/2 term) 20.3 h, Cl(tot) 1.4 l/h, Cl(CVVHF, form 1) 1.4 l/h, and Cl(body) < 0.1 l/h. The average sieving coefficient during the study period was 0.88 +/- 0. 03. The cumulative amount of vancomycin removed by means of CVVHF during the 12-h study period was 245 mg in patient 1 and 228 mg in patient 2. CONCLUSIONS++: CVVHF with a PAN 06 haemofilter effectively removed vancomycin in two critically ill patients. The amount of vancomycin removed with CVVHF was about 250 mg per 12 h. A clear difference in body clearance in the two patients was observed. Our dosage recommendation for vancomycin in critically ill patients receiving CVVHF is a loading dose of 15-20 mg/kg followed after 24 h by 250 to 500 mg twice daily with close monitoring of the serum and ultrafiltrate vancomycin concentration.

Acrylic Resins↗

PubMed2026

Timing matters: Impact of covalent BTK inhibitor dose modifications on outcomes in chronic lymphocytic leukemia/small lymphocytic leukemia-A 7-year real-world study.

BACKGROUND: Covalent BTK inhibitors (cBTKis) are the cornerstone of chronic lymphocytic leukemia (CLL)/small lymphocytic leukemia (SLL) therapy, yet real-world data on dose modifications and their differential impact on long-term outcomes remain incompletely defined. This study investigated the incidence, timing, and the effectiveness of drug switching in a real-world CLL cohort. METHODS: In this 7-year retrospective real-world study, 324 CLL/SLL patients treated at a specialized Shanghai outpatient clinic (April 2018-April 2025; median follow-up, 42 months) were analyzed. Dose modifications were classified as dose interruption (DI) or dose reduction (DR). Their prognostic impact on progression-free (PFS) and overall survival (OS) was assessed by Kaplan-Meier analysis and multivariate Cox regression. RESULTS: The 42-month PFS rate was 70.2%. Of 324 patients, 229 (70.7%) experienced dose reductions or interruptions; infections were the predominant cause (61.9%). The full-dose (FD) group (n = 90) demonstrated superior 4-year PFS (93% vs. 58%, p < .001) and OS (98% vs. 76%, p = .007). Early modifications (0-3 months) were independent predictors of inferior PFS (hazard ratio [HR], 3.93, p = .008) and OS (HR, 3.29, p = .014). Prolonged DI (>14 days) was associated with inferior PFS (HR, 2.64) and OS (HR, 2.15), whereas DR and short DI (≤14 days) had negligible impact. Early (0-3 months) prolonged DI was devastating (3-year PFS, 41.2%; HR, 3.84, p < .001). cBTKi switching (n = 82; 100% nonprogression-driven) shortened DI (median, 6 vs. 14 days) and was independently associated with superior OS (HR, 0.34, p = .018) and PFS (HR, 0.36, p = .022). CONCLUSIONS: Early prolonged DI is the dominant adverse prognostic factor in cBTKi-treated CLL/SLL. Proactive switching minimizes treatment gaps and improves survival, supporting a timing-aware, DI- versus DR-informed approach to dose management.

Humans↗

PubMed1990

[Alternating non-cross resistant multi-drug chemotherapy against malignant lymphoma (CAMBO-VIP)--consideration of the dose intensity].

Dose intensity defined as the amount of drug used per unit time, expressed as mg/m2/week, was reported to be a significant determinant of antitumor activity of single or combined drugs in cancer chemotherapy. We formulated a 12 week high dose intensity chemotherapy (CAMBO-VIP) for the treatment of advanced non Hodgkin's lymphoma with aggressive histology. The treatment consists of weekly alternate administration of myelosuppressive and non-myelosuppressive agents. Doxorubicin was administered every other week in combination with either cyclophosphamide, etoposide or ifosfamide. On the weeks in between, non-myelosuppressive vincristine was given with either methotrexate with leucovorin rescue or bleomycin. Prednisolone was given for the first and the last 4 weeks. Dose reduction and treatment delay were kept minimal for the purpose not lowering dose intensity. As of February 1990, 32 patients (pts), median age 52, entered the study, 29 of whom completed the treatment. There were 3 incomplete cases, in which 2 were due to interruption of the treatment at 5 and 6 weeks, respectively and 1 due to a half dose given because of the old age. CR was obtained in 29 pts (90.6%). Relapse occurred in 3 (10.4%) with the median follow-up of 12 months. Two year disease-free survival (DFS) was estimated to be 76.0% for all the patients and 83.9% for CR patients. Toxicity of CAMBO-VIP was moderate with no chemotherapeutic death. Myelosuppression was severe but of short duration, requiring virtually no dose reduction. Treatment delay was 3 days, median, and maximally 28 days. The average actual dose intensity calculated from given amount of drugs and treatment duration was as high as 90% of the protocol dose intensity. Dose intensity of CAMBO-VIP protocol is highest, equaling to that of MACOP-B, among representative series of reported lymphoma protocols. A highly significant correlation was observed between 9 drug relative dose intensity and DFS of the patients treated with each protocol. Significance of dose intensity as an independent prognostic factor, however, should be determined, by a prospective carefully designed stratified randomized studies.

Aged↗

PubMed2006

Phase II study of interferon-alpha and doxycycline for advanced renal cell carcinoma.

OBJECTIVE: To assess the efficacy and toxicity of the combination of interferon-alpha and doxycycline in patients with metastatic renal cell carcinoma and to assess the effect of this treatment on serum vascular endothelial growth factor (VEGF) levels. PATIENTS AND METHODS: Seventeen patients with Eastern Cooperative Oncology Group (ECOG) performance status of 0 or 1 and life expectancy greater than 4 months with radiologically evident advanced renal cell carcinoma were enrolled. Eight patients had prior nephrectomy and 10 patients were treated within 4 months of their diagnosis. Treatment consisted of interferon-alpha up to 9 million units subcutaneously three times per week and doxycycline 300 mg orally twice per day for weeks one and three of each four-week cycle. Toxicity was evaluated on a biweekly basis and response on a bimonthly basis. VEGF plasma levels were assessed monthly as a measure of potential antiangiogenic effect. RESULTS: No objective responses were seen. The mean duration of study was 2.6 cycles (range: 0.8-6.0 cycles). Three patients (17%) tolerated therapy and displayed stable disease for greater than four months. Five patients withdrew from study before the first response evaluation. Ten patients experienced grade 2 gastrointestinal toxicity requiring dose reduction of doxycycline. Eight patients experienced grade 2 fatigue requiring dose reduction of interferon. VEGF plasma levels were initially suppressed in patients who demonstrated progressive disease but not in patients with stable disease. CONCLUSION: This regimen of doxycycline and interferon-alpha was not efficacious as treatment for renal cell carcinoma. Plasma VEGF levels were significantly decreased during the first two cycles of treatment, but this does not correlate with clinical outcome.

Adult↗

PubMed2004

Identification of less-irradiating tube angulations in invasive cardiology.

OBJECTIVES: We sought to identify tube angulations in invasive cardiology, which promise minimal radiation exposure to patients and operators. BACKGROUND: Radiation exposure in invasive cardiology is high. METHODS: We mapped the fluoroscopic dose-area product per second (DAP/s), applied to an anthropomorphic Alderson-Rando phantom and, in absence of radiation protection devices, the mean personal dose in the operator's position in 10 degrees steps from the 100 degrees right anterior oblique (RAO) to the 100 degrees left anterior oblique (LAO) projection, as well as for all geometrically feasible craniocaudal tube angulations. RESULTS: For our specific setting conditions RAO 20 degrees /0 degrees tube angulation generated the lowest DAP/s and operator's personal dose. The mean patient DAP/s and operator personal dose for all postero-anterior (PA) projections, cranialized and caudalized together, rose significantly: 3.7 and 10.6 times the PA 0 degrees baseline values toward LAO 100 degrees and 3.7 and 2.4 times toward RAO 100 degrees , respectively. Patient and operator values for all PA projections, angulated to the right and left, increased approximately 2.5 times toward 30 degrees craniocaudal angulations. Caudal PA 0 degrees /30 degrees - angulation instead of caudal LAO 60 degrees /20 degrees - angulation for the left coronary main stem and cranial PA 0 degrees /30 degrees + view in place of cranial LAO 60 degrees /20 degrees + view for the left anterior descending coronary artery bifurcation enable 2.6-fold dose reductions to the patient and eight- and five-fold dose reductions to the operator, respectively. CONCLUSIONS: The PA views and RAO views >or=40 degrees , heretofore unconventional in clinical routine, should be favored over steep LAO projections >or=40 degrees whenever possible. Tube angulations that are radiation intensive to the patient exponentially increase the operator's radiation risk.

Angioplasty, Balloon, Coronary↗

PubMed2005

Safety assessment of the conversion from mycophenolate mofetil to enteric-coated mycophenolate sodium in stable renal transplant recipients.

The immunosuppressant mycophenolate mofetil (MMF; CellCept) has greatly improved transplant recipients' clinical outcomes, but its efficacy may be limited by dose adjustments due to adverse events (AEs). An enteric-coated formulation of mycophenolate sodium (EC-MPS; myfortic), designed to improve gastrointestinal tolerability is now available. This Latin-American, prospective, multicenter, open-label, 6-month trial assessed the safety and tolerability of converting renal transplant recipients from MMF to EC-MPS. In total, 237 renal transplant recipients (stable > or = 3 months' posttransplant) receiving MMF (< or =1000 mg b.i.d.) were enrolled. Adults (n = 218) were converted to EC-MPS 720 mg b.i.d. (equimolar to MMF 1000 mg b.i.d.) even if they were initially receiving <1000 mg MMF b.i.d. (ie, 47 adults received a higher than equimolar dose of EC-MPS). Children (n = 19) were converted to EC-MPS 450 or 432 mg/m2 b.i.d. Patients also received cyclosporine microemulsion (Neoral) and corticosteroids. There were three acute rejections and no graft failures. The incidence of AEs was 59.9% (in those receiving a higher than equimolar EC-MPS dose it was 57.4%). In all, 22% of patients had gastrointestinal AEs, 37% had infections, and 4.8% had hematological AEs. Only 24 patients (10%) had an AE-related dose reduction. Seven of these patients had received higher than equimolar doses of EC-MPS. Patients can be safely converted from different doses of MMF to a standard dose of EC-MPS. The requirement for EC-MPS dose reduction to manage AEs was relatively low. Use of EC-MPS is a valid alternative for renal transplant recipients receiving maintenance MMF treatment.

Adolescent↗

PubMed1994

Sex hormone receptor binding, progestin selectivity, and the new oral contraceptives.

The desired biologic effect of progestins used in OCs is progestational activity. Undesired pharmacologic properties such as androgenic activity are not necessary for contraception and increase the potential for adverse effects. A selective progestin has progestational effects at relatively low concentrations or doses and androgenic effects at only relatively high concentrations or doses. The degree to which progestational activity is maximized and androgenic activity is minimized is a measure of a progestin's selectivity. The ratio of its affinity for progesterone receptors to its affinity for androgen receptors is the selectivity index. To minimize the androgenic side effects associated with the older progestins, the doses used in OCs have been reduced over the years. These dose reductions have decreased the potential for undesired androgenic effects but also have negatively affected cycle control. Three new progestins, norgestimate, desogestrel, and gestodene, have relatively greater affinity for progesterone receptors than for androgen receptors when compared with the older agents, permitting a reduction in androgenic side effects without the need for further dose reduction. Preclinical receptor-binding studies and animal pharmacologic studies have documented the higher selectivity indexes of these new progestins. Their higher ratios of progestational to androgenic activity provide the basis for the reduction in androgenic adverse effects observed with their clinical use.

Animals↗

PubMed2003

An analytical dosimetry model as a step towards accounting for inhomogeneities and bounded geometries in 192Ir brachytherapy treatment planning.

A simple analytical dose rate calculation model based on primary and scatter separation that treats 192Ir as a monoenergetic source by use of appropriate attenuation and mass energy absorption coefficients is documented for accurate dosimetry in water. This model is then generalized and tested for use in any homogeneous tissue material of radiobiological interest using scatter to primary ratios calculated in water with a material density scaling to account for the difference in the scattering properties of these materials and water. The potential of the analytical model for predicting the effect of the interference of an inhomogeneity is then evaluated by comparison with corresponding Monte Carlo calculations. It is found that regardless of the inhomogeneity dimensions and position relative to the source, the model is capable of increased accuracy (better than 2%) in calculating the primary dose rate at any point not only for low-Z tissue materials but also for high-Z shielding materials where a severe hardening of the primary photons occurs. Overall, for low-Z tissue inhomogeneities the proposed model succeeds in correcting dosimetry results towards the right direction compared to commercial treatment planning systems that currently ignore the effect of phantom dimensions and inhomogeneity interference. Regarding high-Z shielding materials the proposed model accurately predicts the dose reduction just beyond the inhomogeneity (for example it predicts a dose reduction of 47% just behind a tungsten alloy cylinder of 1 cm diameter and 2 mm thickness placed at 1.4 cm away from an 192Ir source, in agreement with corresponding results in the literature) but does not account for the increasing contribution of the laterally scattered photons with increasing distance from the bounded inhomogeneity.

Algorithms↗

PubMed1994

Patient care issues: the management of paclitaxel-related toxicities.

At the low-to-moderate doses that are recommended, paclitaxel is a well-tolerated drug. Although adverse reactions do occur, most of these are manageable and do not have a long-lasting effect on the patients' quality of life. The starting dose of paclitaxel, as approved by the Food and Drug Administration for refractory ovarian cancer, is 135 mg/m2. A slightly higher dose (175 mg/m2) is being investigated for heavily pretreated patients with metastatic breast cancer. In the investigational setting, the highest dose that may safely be administered when paclitaxel is used as a single agent is 250 mg/m2 for minimally pretreated patients. If G-CSF is also given, the same dose may safely be administered to heavily pretreated patients. When paclitaxel is administered in combination with cisplatin, a dose of 135 mg/m2 may safely be given prior to cisplatin, which is administered at a dose of 75 mg/m2. These dose levels may be increased when G-CSF is also used. Dose modifications should be considered only in patients who experience severe neutropenia or neurotoxicity. Patients who received high doses of paclitaxel in Phase II trials frequently required dose reductions. However, when the drug is administered at the recommended dose of 135 mg/m2, neutropenia does not often necessitate further dose reduction. Hematopoietic growth factors, such as G-CSF, seem to be helpful in preventing prolonged grade IV and febrile neutropenia, and in avoiding treatment delays for longer than one week.(ABSTRACT TRUNCATED AT 250 WORDS)

Clinical Trials, Phase I as Topic↗

PubMed2001

A practical approach to the first iteration in the optimization of radiation dose and image quality in CT: estimates of the collective dose savings achieved.

CT is a diagnostic imaging modality giving higher patient dose in comparison with other radiological procedures. It contributed an estimated 20% to the collective effective dose to the UK population from medical X-rays in 1990, rising to an estimated 40% in 1999. Tremendous national effort has been expended in reducing patient doses from other radiological procedures with considerable success, but much of the collective dose reduction achieved has been offset by a corresponding increase in the collective dose from CT. Over a period of about 2 years, following the installation of a helical CT scanner, CT scan parameters in this hospital have been adjusted with the aim of working towards optimization of image quality and patient dose. A 33% reduction in annual collective effective dose has been achieved, from about 16.5 manSv to 11 manSv. However, despite this dose reduction, the annual collective effective dose to our sub-population is 2.8 times the value 9 years ago. The increase is almost entirely the result of an increased application of CT; 6149 examinations per annum in 1999 compared with 2210 in 1991. The crucial importance of reducing patient doses from this modality is discussed. Indicative effective doses and image noise values are presented for examination protocols approaching optimization.

Humans↗

PubMed1997

Single-agent paclitaxel in advanced non-small cell lung cancer: single-center phase II study using a 3-hour administration schedule.

The efficacy and safety of paclitaxel (Taxol; Bristol-Myers Squibb Company, Princeton, NJ) administered as a 3-hour infusion was investigated in a phase II study involving 21 patients with stage III/IV non-small cell lung cancer. The study included two quality of life assessments (the Hospital Anxiety and Depression Scale and the Rotterdam Symptom Checklist) to test their suitability for use in a future randomized phase III trial of paclitaxel and best supportive care versus best supportive care alone. Four (19%) of the 21 patients (95% confidence interval, 8% to 38%) achieved a partial response. The median time to disease progression for all patients entered was 19 weeks. Paclitaxel was well tolerated, with dose reduction required in only one patient because of arthralgia/myalgia. No dose reductions, delays, or discontinuations were required for hematologic toxicity. Completion and compliance with quality of life questionnaires was high, and these research tools proved to be acceptable for future use in phase III studies with paclitaxel.

Adult↗

PubMed2005

Safety and efficacy of two different doses of capecitabine in the treatment of advanced breast cancer in older women.

PURPOSE: To evaluate the safety and efficacy of capecitabine in older women with advanced breast cancer. PATIENTS AND METHODS: Seventy-three eligible patients (median age, 73 years; range, 65 to 89 years) were enrolled. The first 30 patients received oral capecitabine 1,250 mg/m(2) twice daily on days 1 to 14 every 21 days. Due to the occurrence of two toxic deaths, capecitabine 1,000 mg/m(2) twice daily was given to the subsequent 43 patients. RESULTS: All patients were assessable for safety and efficacy. A total of 351 treatment cycles were administered (median, six per patient; range, one to eight cycles). Dose reductions due to toxicities were required in 30% of patients in the standard-dose group, but capecitabine was given without a dose reduction to 95% of patients in the low-dose group. Capecitabine demonstrated a favorable safety profile. The overall incidence of grade 3/4 toxicities was low: the most common events reported in </= 10% of the patients were fatigue, diarrhea, dyspnea, and nausea. In the standard-dose group, the response rate was 36.7% (95% CI, 19.9% to 56.1%). An additional seven patients had disease stabilization at >/= 24 weeks. In the low-dose group, the response rate was 34.9% (95% CI, 21% to 50.9%). An additional 15 patients had prolonged stabilization. The median time to disease progression was 4 months in either group. CONCLUSION: This study shows that capecitabine is safe and effective in the elderly breast cancer patient. Based on the overall results, the capecitabine dose of 1,000 mg/m(2) twice daily merits consideration as "standard" for older patients who do not have severely impaired renal function.

Administration, Oral↗