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M Brada

Publications and source records attributed to M Brada.

At least 91 records · Page 5Linked to original sources
PubMed1995

Improving the acceptability of high-dose radiotherapy by reducing the duration of treatment: accelerated radiotherapy in high-grade glioma.

Radiotherapy, although clearly beneficial in patients with high-grade glioma, is largely palliative, and a protracted course of treatment may not be the most appropriate approach in the context of limited survival. We therefore assessed the feasibility, toxicity and survival results of a short accelerated radiotherapy regimen given twice daily over a period of 3 weeks. A total of 116 patients with high-grade glioma were treated with radiotherapy in a prospective study using an accelerated fractionation regimen. The total dose of 55 Gy was given in 32-36 fractions of 1.72-1.53 Gy, twice daily 5 days a week, with a minimum 6 h interval between fractions. Toxicity was assessed using Karnofsky performance status scale and in the later part of the study with the Barthel index. Survival data were compared with a control group treated with 60 Gy in 30 daily fractions in a previous MRC study, matched for known prognostic factors. The median survival of 116 patients treated with accelerated radiotherapy was 10 months. Survival comparison of accelerated patients with matched controls treated with conventional fractionation demonstrated a hazard ratio of 1.13 (95% confidence interval 0.85-1.51; P = 0.39). Early treatment toxicity was acceptable, with only seven patients developing transient decrease in performance status. The accelerated radiotherapy regimen was logistically feasible and acceptable to patients, carers and staff. Treatment time was reduced without apparent increase in early toxicity and there was no loss of survival benefit. The effectiveness and convenience of a short accelerated regimen makes this a suitable alternative to a 6 week course of radiotherapy in patients with high-grade glioma. However, a full randomised trial comparing conventional and accelerated radiotherapy may be required as proof of equivalence.

Actuarial Analysis↗
PubMed1995

Modifying the Barthel Performance Index Score for use in patients with brain tumours.

Performance status scores are useful tools in the management of patients with malignant disease. No specific performance index score exist, however, for patients with glioma. The Barthel Index, has been used in our department because it has been widely used in patients following stroke and found useful. This study aims to establish whether a modification of the Barthel Index would be more appropriate for patients with glioma and, if so, what modifications should be made. The opinions of multidisciplinary health workers and carers experienced in helping patients with glioma were established by questionnaire. Difficulty with speech and the presence of seizures were statistically ranked the most significant disability in terms of overall performance status. As these are not included in the Barthel Index a modification is justified. However, to include new categories in a performance index but avoid increasing its complexity, existing categories have to be omitted. Therefore, the second aim of this study was to establish which categories within the Barthel contribute least to a change in the total score. Three-hundred-and-thirty-three prospectively recorded Barthel scores were evaluated in 81 patients over 2 years and the individual categories evaluated by multifactor analysis. The sensitivity of the categories 'bowel function' and 'independence in grooming' to a change in the total score was less than 1%. In conclusion, substituting 'speech difficulties' and the presence of seizure in place of 'bowel function' and 'independence in grooming' from the Barthel Index will improve the specificity for patients with glioma without reducing the sensitivity or acceptability for the patients and research nurses who most often complete them.(ABSTRACT TRUNCATED AT 250 WORDS)

Activities of Daily Living↗
PubMed1995

Radiotherapy for primary and secondary brain tumors.

The past 2 years have seen publications of many studies on refinement of conventional radiotherapy using altered fractionation, sensitizers, and high-precision radiotherapy techniques, particularly in the form of stereotactic radiotherapy or radiosurgery. In less common tumors such as cranial germ cell tumors and primary central nervous system lymphoma, the trend towards exploring the role of chemotherapy continues. Mature clinical and experimental studies have also been published that provide detailed and clinically important information on the radiation tolerance of the spinal cord.

Brain Neoplasms↗
PubMed1994

The management of histologically unverified presumed cerebral gliomas with radiotherapy.

PURPOSE: To define the natural history, and prognostic factors of patients with histologically unverified presumed gliomas diagnosed on CT or MR imaging, and treated with external beam radiotherapy. METHODS AND MATERIALS: Retrospective review of 111 adults with histologically unverified presumed cerebral glioma treated with radiotherapy between 1974 and 1990. Using CT or MRI criteria alone 41 were presumed low grade, 63 high grade gliomas and 7 were unclassified. Survival results were compared to a cohort of 82 adults with histologically verified low grade gliomas treated over the same period with surgery and radiotherapy. RESULTS: The 5 year survival probability of the whole cohort was 31%. Age, performance status, and the degree of contrast enhancement were independent prognostic factors for survival. Patients with presumed low grade glioma had a 5 year survival of 41% compared to 52% for patients with verified low grade glioma. After correction for prognostic factors no significant difference was found in the survival between patients with verified and unverified low grade tumors. One of 15 cases with subsequent histology, obtained at autopsy or salvage surgery, had nonglial pathology. CONCLUSION: Patients diagnosed on the basis of clinical features and imaging as having presumed glioma have similar natural history and clinical behavior after treatment with radiotherapy to those with histologically confirmed gliomas. However, the results should not be taken as justification for avoiding biopsy. A proportion of patients may have nonglial pathology and new more effective treatment strategies for patients with glial tumors can only evolve on the basis of full diagnostic information including pathology.

Adolescent↗
PubMed1994

Radiosurgery/stereotactic external beam radiotherapy for malignant brain tumours: the Royal Marsden Hospital experience.

SRT is a high-precision technique of radiotherapy which delivers focused irradiation to small target volumes. In the context of external beam radiotherapy it can be described as stereotactically guided conformal radiotherapy. As the technique originated from neurosurgical technology, it has initially been limited to single fraction treatment. However, with the use of relocatable fixation devices the way ahead particularly in its application in the treatment of brain tumours is in fractionated SRT. Currently, single fraction SRT/radiosurgery is of proven value only in the treatment of small inoperable arteriovenous malformations. It is being exploited in the management of brain tumours but so far remains as experimental treatment. We have demonstrated that fractionated SRT in patients with gliomas is a non-invasive equivalent to brachytherapy and in patients with solitary metastases a non-invasive alternative to surgical excision. However, the treatment is not without side effects, and the long-term effectiveness and toxicity of SRT, particularly with the use of unconventional fractionation, is not defined. The future use of SRT in the treatment of brain tumours should not be guided simply by the technical possibilities but by a rational appraisal of all treatment options to achieve the best disease control, survival and toxicity. Although there is potential for benefit in a number of small tumours, SRT cannot at present be recommended as the primary treatment in any tumour. In addition, its use should be discouraged in the treatment of unbiopsied brain lesions and as the major form of treatment of pineal germinomas. The technology of stereotactic radiotherapy is evolving, and it is likely that SRT will be integrated into conventional radiotherapy practice to become simply a high-precision technique of radiotherapy delivery in everyday use.

Actuarial Analysis↗
PubMed1994

Hypofractionated radiotherapy as palliative treatment in poor prognosis patients with high grade glioma.

We report the palliative effectiveness of a hypofractionated radiotherapy regimen in patients with poor prognosis high grade glioma. Thirty-eight elderly, and/or disabled patients received radiotherapy to a dose of 30 Gy in 6 fractions over 2 weeks to a planning target volume defined by the enhancing tumour and a 2-cm margin. The median survival was 6 months with a 1-year survival rate of 23%. Treatment was without acute toxicity. One month after radiotherapy, functional status, assessed using a verbally administered Barthel index, improved in 38% and remained stable in a further 39% of surviving patients. At 3 months 39% of surviving patients had improved and a further 12% remained stable. We conclude that in the poor prognostic group of patients with high grade glioma hypofractionated partial brain radiotherapy is well tolerated, convenient and provides effective palliation in a proportion of patients. Comparison with conventional radiotherapy or symptomatic care alone require further evaluation in randomised studies.

Activities of Daily Living↗
PubMed1994

Quality assurance in fractionated stereotactic radiotherapy.

The recent development of fractionated stereotactic radiotherapy (SRT), which utilises the relocatable Gill-Thomas-Cosman frame (GTC 'repeat localiser'), requires comprehensive quality assurance (QA). This paper focuses on those QA procedures particularly relevant to fractionated SRT treatments, and which have been derived from the technique used at the Royal Marsden Hospital. They primarily relate to the following: (i) GTC frame fitting, initially in the mould room, and then at each imaging session and treatment fraction; (ii) checking of the linear accelerator beam geometry and alignment lasers; and (iii) setting up of the patient for each fraction of treatment. The precision of the fractionated technique therefore depends on monitoring the GTC frame relocation at each fitting, checking the accuracy of the radiation isocentre of the treatment unit, its coincidence with the patient alignment lasers and the adjustments required to set the patient up accurately. The results of our quality control checks show that setting up to a mean radiation isocentre using precisely set-up alignment lasers can be achievable to within 1 mm accuracy. When this is combined with a mean GTC frame relocatability of 1 mm on the patient, a 2-mm allowance between the prescribed isodose surface and the defined target volume is a realistic safety margin for this technique.

Brain Neoplasms↗
PubMed1994

Survival in patients with recurrent glioma as a measure of treatment efficacy: prognostic factors following nitrosourea chemotherapy.

The assessment of efficacy of treatment in patients with recurrent glioma is notoriously difficult, and survival is the most objective endpoint. Between 1970 and 1992, a cohort of 211 patients with recurrent glioma received nitrosourea-based chemotherapy at the time of disease progression. The median survival from the start of chemotherapy was 7 months, with 30% 1-year and 10% 2-year survival probabilities. One-year survival was 22% in 147 patients with recurrent high-grade astrocytoma, 41% in 37 patients with low-grade astrocytoma and 45% in 24 patients with oligodendroglioma. Age, histological grade and Karnofsky performance status (KPS) at recurrence were independent prognostic factors for survival on multivariate analysis. Based on patients' age, tumour grade and KPS, it was possible to define three distinct prognostic groups with 1-year survival probabilities of 60, 21 and 17% (P < 0.005). Response to chemotherapy was difficult to assess but correlated with prognostic subgroup, with highest response rate (46%) in the most favourable group and lowest (13%) in the poor prognostic group. In patients with recurrent glioma, patient and tumour parameters are the major determinants of outcome which are identical to prognostic factors at the time of primary diagnosis. They can be used to provide prognostic information for the individual patient, and to stratify patients particularly in trials assessing the efficacy of novel treatments.

Adolescent↗
PubMed1994

Haematological toxicity of radiotherapy following high-dose chemotherapy and autologous bone marrow transplantation in patients with recurrent Hodgkin's disease.

17 patients with recurrent Hodgkin's disease received 21 courses of radiotherapy (RT) 1-23 months after high-dose chemotherapy and autologous bone marrow transplantation. WHO grade III-IV haematological toxicity, of median duration 38 days (range 4-236), was observed following 10 courses of radiotherapy in 9 patients. This haematological morbidity could be predicted with an 80.0% sensitivity when the pre-RT white cell count was < 5 x 10(9)/l or the platelet count < 100 x 10(9)/l. It occurred in 9/11 patients with initial stage III-IV disease, including all 6 given extended radiotherapy fields, but in no patients with initial stage II disease (chi 2 = 9.35, P < 0.005). Age, histology, the presence of B symptoms, performance status, previous radiotherapy or chemotherapy, the interval between autologous bone marrow transplantation and radiotherapy, the high-dose regimen used, and the radiotherapy dose or field size, did not appear to affect haematological toxicity. The median survival was 18 months from the date of starting radiotherapy. 7 patients remain alive and progression-free 8-51 months (median 21 months) after radiotherapy. Radiotherapy may contribute to durable remissions in patients with relapsed or residual Hodgkin's disease after autologous bone marrow transplantation, but significant haematological toxicity may be expected in those with mild pancytopaenia prior to radiotherapy, particularly with initial stage III or IV disease.

Adolescent↗
PubMed1994

Who should follow up cancer patients? Nurse specialist based outpatient care and the introduction of a phone clinic system.

The objective of this study was to pilot and evaluate a nurse based follow-up system for oncology patients in terms of feasibility and impact on outpatient oncology practice. We identified clinical situations with a defined range of clinical problems, which were set out on a proforma (Appendix) for a nurse consultation. Following a period of training, surveillance during radiotherapy was transferred to a nurse 'on treatment clinic' and a defined point of post-treatment follow-up to a nurse 'phone clinic'. The effectiveness of the nurse based follow-up was assessed by a prospective analysis of the consultation records. The impact on clinical practice was assessed in the form of audit of the clinic work-load before and after introduction of the nurse follow-up service. The patient assessment by the nurse specialist was satisfactory and covered the range of problems encountered. Medical referral by the nurse specialist was necessary in 3/33 on treatment assessments and 1/61 phone appointments. The medical outpatient work-load was estimated to decrease by 30%. Structured follow-up by a skilled and trained nurse specialist provides excellent support and effective medical surveillance in defined situations in oncology follow-up. Patients appeared satisfied with the arrangement and the pilot study suggested up to 30% reduction in the medical outpatient work-load. The use of 'phone clinics' offers an effective alternative to the conventional outpatient clinic model, while being less costly and more convenient for patients and staff.

Ambulatory Care Facilities↗
PubMed1994

Peripheral blood involvement in non-Hodgkin's lymphoma detected by clonal gene rearrangement as a biological prognostic marker.

Peripheral blood from 67 patients with non-Hodgkin's lymphoma was examined at initial diagnosis for the presence of circulating lymphoma cells by DNA hybridisation using immunoglobulin and T-cell receptor gene probes. Clonal gene rearrangement was found in 31% (21/67) of patients and correlated with clinical stage, histological grade and bone marrow involvement. Clinical stage and the presence of lymphoma cells in peripheral blood were prognostic factors for progression-free survival in all patients on univariate analysis, but the detection of lymphoma cells was not independent of stage. It was also not a significant predictor for survival. In patients with intermediate- and high-grade lymphoma, the detection of lymphoma cells in peripheral blood was a significant prognostic factor for progression-free survival (PFS) and survival only on univariate analysis. The 3-year PFS was 17% in patients with circulating lymphoma cells compared with 75% if these were absent (P < 0.05). The presence of lymphoma cells in peripheral blood is associated with extensive disease and may be a biological marker of poor disease control. Sensitive techniques of detection should form part of large prospective studies in non-Hodgkin's lymphoma.

Adult↗
PubMed1994

Bone mineralization after treatment of growth hormone deficiency in survivors of childhood malignancy.

Having noted symptomatic osteoporotic vertebral collapse in young adult survivors of childhood malignancy, bone mineral density (BMD) was examined at three sites by dual-energy X-ray absorptiometry in 64 patients treated in childhood for intracranial malignancy (group 1; n = 21) or acute leukaemia (group 2; n = 43). Patients in group 1 were selected for growth hormone deficiency (GHD) by auxological and biochemical criteria before the end of puberty (Tanner stage V). Seven patients (six men; mean (+/- SEM) age at study, 28.0 +/- 2.9 years; mean age at diagnosis, 8.7 +/- 1.5 years) in this group had been treated with human pituitary growth hormone (GH) for 1-12 years; and 14 patients (nine men; mean age at study, 26.8 +/- 1.0 years; mean age at diagnosis, 10.7 +/- 1.4 years) had not received GH. Bone densities in group 1 were normal in the GH-treated patients at the femoral neck (98.4 +/- 3.8% of control), lumbar spine (100.4 +/- 6.1% of control) and Ward's triangle (101.0 +/- 6.1% of control) but markedly reduced in the untreated group (femoral neck, 81.2 +/- 2.6% of control (p = 0.002); lumbar spine, 79.1 +/- 4.1% of control (p = 0.04); Ward's triangle, 80.1 +/- 3.6% of control (p = 0.01)). The majority of patients in group 2 had been treated for acute lymphoblastic leukaemia (ALL) and were in three subgroups.(ABSTRACT TRUNCATED AT 250 WORDS)

Acute Disease↗
PubMed1993

Craniopharyngioma--a long-term results following limited surgery and radiotherapy.

Between 1950 and 1986 173 patients with craniopharyngioma were treated at the Royal Marsden Hospital with external beam radiotherapy either alone or following surgery. Four patients had complete tumour excision, 21 subtotal and 78 partial resection, 14 had biopsy alone, 34 aspiration alone and 22 had no surgery directed at tumour eradication. Seventy-seven (45%) were children (aged < 16 years). The 10 and 20 year progression-free survival (PFS) rates were 83% and 79%. There were no independent prognostic factors for PFS. The 10 and 20 year survival rates were 77% and 66% at a median follow-up of 12 years. After adjustment for mortality in the normal population, age and technique of radiotherapy (which corresponded with era of treatment) were significant independent prognostic factors for survival. The risk of death (corrected for mortality from natural causes and controlling for radiotherapy technique) for age groups 16-39 and > or = 40 was 0.58 and 0.40 respectively, relative to a risk of 1.0 for the age group < 16 years. Survival and PFS were not influenced by the extent of surgical excision. Visual field defect improved after radiotherapy in 36% of patients (38/106) and visual acuity in 30% (27/91). No patient developed radiation optic neuropathy. We conclude that limited surgery and radiotherapy achieve excellent long-term tumour control and survival with low morbidity.

Adolescent↗
PubMed1993

Efficacy and toxicity of fractionated stereotactic radiotherapy in the treatment of recurrent gliomas (phase I/II study).

Twenty-two patients with recurrent glioma have been treated on a dose escalation protocol with fractionated stereotactic external beam radiotherapy (SRT). All had previously received radical radiotherapy (median dose 55 Gy) as part of the initial treatment. The dose of SRT was increased from 30 Gy in six fractions to 50 Gy in ten fractions. Median survival from the date of SRT was 9.8 months. There was no significant acute morbidity but five patients who received > or = 40 Gy developed steroid responsive neurological deterioration assumed to represent late radiation damage. The survival and toxicity in patients with recurrent glioma are comparable with interstitial therapy. Fractionated SRT is a noninvasive form of localised radiation which may be a suitable alternative to interstitial therapy in this group of patients.

Adolescent↗
PubMed1993

Stereotactic radiotherapy of irregular targets: a comparison between static conformal beams and non-coplanar arcs.

Stereotactic radiotherapy using a linear accelerator is usually equated with the technique of delivery using multiple non-coplanar arcs, which achieves a spherical dose distribution. As the majority of intracranial lesions are not spherical, a range of schematized tumour shapes were planned to assess the role of static conformal beams in the treatment of irregular lesions. A sphere and 2 ellipsoids, ranging from 20 to 50 mm maximum diameter located intracranially were planned using 3, 4, and 6 non-coplanar static beams with conformal blocks and were compared with four 120 degree non-coplanar arcs. Comparison of the plans was made by the relative sparing of normal tissue outside the target volume using three-dimensional dose-volume distributions. Non-coplanar arcs spared more normal tissue at low isodoses and achieved the best high dose sparing for spherical targets. For the majority of irregular targets, 3 and 4 static beams spared more tissue at doses > or = 50% and > or = 80% than the arc technique. For all irregular volumes, maximum sparing of normal tissue to isodoses > or = 50% and > or = 80% of the treatment isodose was obtained with 6 static conformal beams. We conclude that irregularly shaped tumours suitable for stereotactic radiotherapy with a linear accelerator are better treated with conformal static non-coplanar beams rather than with the multiple arc technique.

Female↗
PubMed1993

Fractionated stereotactic external beam radiotherapy in the management of brain metastases.

24 patients with 28 brain metastases were treated with fractionated stereotactic radiotherapy (SRT). Doses ranged from 10 Gy in two fractions to 20 Gy in two fractions. 13 patients received SRT boost after whole brain radiotherapy (WBRT), 5 were treated with SRT alone and 6 were treated at the time of recurrence following WBRT. The median progression-free survival at the treated site was 18 months and the median survival was 18 months. All patients were treated without admission to hospital. Toxicity of fractionated SRT was minimal and patients treated without WBRT did not suffer significant alopecia. Fractionated SRT offers a non-toxic non-invasive alternative to excision surgery in patients with solitary brain metastases. The optimum fractionation schedule and the role of whole brain irradiation remain to be determined.

Adult↗