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ABSTRACT: Breast cancers are evolving, multi-scale systems that are characterized by varied complex spatial structures. In this study, we measured the structural characteristics of 33 breast tumours in patients who were to receive neoadjuvant chemotherapy using dynamic contrast enhanced MRI and fractal geometry. The results showed a significant association between fractal measurements and tumour characteristics. The fractal dimension was associated with receptor status (ER and PR) and the fractal fit was associated with response to chemotherapy, measured using a validated pathological response scale, tumour grade and size. This study describes structure measures that may be a consequence of known prognostic factors during the initial and/or maturation phase of tumour growth. These results suggest that measuring tumour structure in this way can predict an individual's response to neoadjuvant therapy and may identify those who will benefit least from neoadjuvant chemotherapy, allowing alternative treatment options to be selected in those patients.
Breast Cancer Research and Treatment 03/2012; 133(3):1199-206. · 4.43 Impact Factor
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ABSTRACT: Surgery for oesophageal cancer remains the only means of cure for invasive tumours. It is claimed that the surgical approach for these cancers impacts on morbidity and may influence the ability to achieve tumour clearance and therefore survival, however there is no conclusive evidence to support one approach over another. This study aims to determine the impact of operative approach on tumour margin involvement and survival.
Data were extracted from the Scottish Audit of Gastric and Oesophageal Cancer (SAGOC), a prospective population-based audit of all oesophageal and gastric cancers in Scotland between 1997 and 1999 with a minimum of five-year follow up. Analysis focused on the three commonest approaches (Ivor Lewis n = 140, transhiatal n = 68, left thoraco-laparotomy n = 142) for oesophageal cancer.
Operative approach had no significant impact on post-operative morbidity, mortality, overall margin involvement and survival. Transhiatal approach resulted in significantly more circumferential margin involvement (p = 0.019), and the presence of circumferential margin involvement significantly reduced five-year survival (median survival 13 months) compared to no margin involvement (median survival 25 months, p = 0.001).
Surgical approach for oesophageal cancer had no significant effect on morbidity, post-operative mortality and five-year survival. Non-selective use of the transhiatal approach is associated with a significantly greater circumferential margin involvement, with positive circumferential margin impacting adversely on 5-year survival.
European journal of surgical oncology: the journal of the European Society of Surgical Oncology and the British Association of Surgical Oncology 12/2011; 38(2):157-65. · 2.56 Impact Factor
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ABSTRACT: The objective of this work was to propose and demonstrate a novel technique for the assessment of tumour pharmacokinetic parameters together with a regionally estimated vascular input function. A breast cancer patient T2*-weighted dynamic contrast enhanced MRI (DCE-MRI) dataset acquired at high temporal resolution during the first-pass bolus perfusion was used for testing the technique. Extraction of the lesion volume transfer constant K(trans) together with the intravascular plasma volume fraction v(p) was achieved by optimizing a capillary input function with a measure of cardiac output using the principle of intravascular indicator dilution theory. For a region of interest drawn within the breast lesion a v(p) of 0.16 and a K(trans) of 0.70 min(-1) were estimated. Despite the value of v(p) being higher than expected, estimated K(trans) was in accordance with the literature values. In conclusion, the technique proposed here, has the main advantage of allowing the estimation of breast tumour pharmacokinetic parameters from first-pass perfusion T2*-weighted DCE-MRI data without the need of measuring an arterial input function. The technique may also have applicability to T1-weighted DCE-MRI data.
Physics in Medicine and Biology 02/2011; 56(6):1743-53. · 2.83 Impact Factor
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ABSTRACT: As part of the Magnetic Resonance Imaging for Breast Screening (MARIBS), Study women with a family history of breast cancer were assessed psychologically to determine the relative psychological impact and acceptability of annual screening using magnetic resonance imaging (MRI) and conventional X-ray mammography (XRM).
Women were assessed psychologically at baseline (4 weeks before MRI and XRM), immediately before, and immediately after, both MRI and XRM, and at follow-up (6 weeks after the scans).
Overall, both procedures were found to be acceptable with high levels of satisfaction (MRI, 96.3% and XRM, 97.7%; NS) and low levels of psychological morbidity throughout, particularly at 6-week follow-up. Low levels of self-reported distress were reported for both procedures (MRI, 13.5% and XRM, 7.8%), although MRI was more distressing (P=0.005). Similarly, higher anticipatory anxiety was reported before MRI than before XRM (P=0.003). Relative to XRM, MRI-related distress was more likely to persist at 6 weeks after the scans in the form of intrusive MRI-related thoughts (P=0.006) and total MRI-related distress (P=0.014). More women stated that they intended to return for XRM (96.3%) than for MRI (88%; P<0.0005). These effects were most marked for the first year of screening, although they were also statistically significant in subsequent years.
Given the proven benefits of MRI in screening for breast cancer in this population, these data point to the urgent need to provide timely information and support to women undergoing MRI.
British Journal of Cancer 02/2011; 104(4):578-86. · 5.04 Impact Factor
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ABSTRACT: Times Cited: 0
Meeting Abstract
English
Cited References Count: 0
670UN
W B SAUNDERS CO LTD
32 JAMESTOWN RD, LONDON NW1 7BY, ENGLAND
LONDON
Suppl. 2
Osteoarthritis and Cartilage 10/2010; 18:S179-S180. · 3.90 Impact Factor
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ABSTRACT: The purpose of this work is to quantify the accuracy of pharmacokinetic parameter measurement in DCE-MRI of breast cancer at 3 T in relation to three sources of error. Individually, T1 measurement error, temporal resolution and transmitted RF field inhomogeneity are considered. Dynamic contrast enhancement curves were simulated using standard acquisition parameters of a DCE-MRI protocol. Errors on pre-contrast T1 due to incorrect RF spoiling were considered. Flip angle errors were measured and introduced into the fitting routine, and temporal resolution was also varied. The error in fitted pharmacokinetic parameters, K(trans) and v(e), was calculated. Flip angles were found to be reduced by up to 55% of the expected value. The resultant errors in our range of K(trans) and v(e) were found to be up to 66% and 74%, respectively. Incorrect T1 estimation results in K(trans) and v(e) errors up to 531% and 233%, respectively. When the temporal resolution is reduced from 10 to 70 s K(trans) drops by up to 48%, while v(e) shows negligible variation. In combination, uncertainties in tissue T1 map and applied flip angle were shown to contribute to errors of up to 88% in K(trans) and 73% in v(e). These results demonstrate the importance of high temporal resolution, accurate T1 measurement and good B1 homogeneity.
Physics in Medicine and Biology 01/2010; 55(1):121-32. · 2.83 Impact Factor
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unpublished. 01/2008; submitted:-.
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ABSTRACT: Times Cited: 0
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Cited References Count: 0
181QQ
AMER SOC BONE & MINERAL RES
2025 M ST, N W, STE 800, WASHINGTON, DC 20036-3309 USA
WASHINGTON
Journal of Bone and Mineral Research 07/2007; 22(7):1133. · 6.37 Impact Factor
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ABSTRACT: Guidelines suggest that surgery for oesophageal and gastric cancer should be conducted in large cancer centres. This national study examined the relationship between hospital volume and outcome in Scotland.
This was a prospective, population-based study of 3293 consecutive patients with oesophageal or gastric cancer diagnosed between 1997 and 1999. Some 1302 patients underwent surgery and were followed for 5 years after operation.
The 5-year adjusted overall survival rate for the 3293 patients was 18.7 (95 per cent confidence interval (c.i.) 17.2 to 20.2) per cent and that after surgical resection was 39.6 (95 per cent c.i. 36.3 to 43.0) per cent. Death within 1 year after surgical resection was associated with a postoperative complication (odds ratio (OR) 2.5 (95 per cent c.i. 1.6 to 3.8); P < 0.001) or resection margin involvement by tumour (OR 7.2 (95 per cent c.i. 1.1 to 47.5); P = 0.042) after adjustment for age, sex and tumour location. There was no relationship between hospital volume and postoperative morbidity or mortality, nor between survival and volume of patients either for hospital of diagnosis or hospital of surgery.
This population-based study of oesophageal and gastric cancer suggests that the link between hospital volume and long-term survival for patients undergoing surgery requires re-evaluation.
British Journal of Surgery 05/2007; 94(5):578-84. · 4.61 Impact Factor
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Proceedings of the Society for Magnetic Resonance in Medicine; 01/2007
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I Griebsch,
J Brown,
C Boggis,
A Dixon,
M Dixon,
D Easton,
R Eeles,
D G Evans, F J Gilbert,
J Hawnaur, [......],
S M Moss,
A Nerurkar,
A R Padhani,
L J Pointon,
J Potterton,
D Thompson,
L W Turnbull,
L G Walker,
R Warren,
M O Leach
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ABSTRACT: Contrast enhanced magnetic resonance imaging (CE MRI) is the most sensitive tool for screening women who are at high familial risk of breast cancer. Our aim in this study was to assess the cost-effectiveness of X-ray mammography (XRM), CE MRI or both strategies combined. In total, 649 women were enrolled in the MARIBS study and screened with both CE MRI and mammography resulting in 1881 screens and 1-7 individual annual screening events. Women aged 35-49 years at high risk of breast cancer, either because they have a strong family history of breast cancer or are tested carriers of a BRCA1, BRCA2 or TP53 mutation or are at a 50% risk of having inherited such a mutation, were recruited from 22 centres and offered annual MRI and XRM for between 2 and 7 years. Information on the number and type of further investigations was collected and specifically calculated unit costs were used to calculate the incremental cost per cancer detected. The numbers of cancer detected was 13 for mammography, 27 for CE MRI and 33 for mammography and CE MRI combined. In the subgroup of BRCA1 (BRCA2) mutation carriers or of women having a first degree relative with a mutation in BRCA1 (BRCA2) corresponding numbers were 3 (6), 12 (7) and 12 (11), respectively. For all women, the incremental cost per cancer detected with CE MRI and mammography combined was pound28 284 compared to mammography. When only BRCA1 or the BRCA2 groups were considered, this cost would be reduced to pound11 731 (CE MRI vs mammography) and pound15 302 (CE MRI and mammography vs mammography). Results were most sensitive to the unit cost estimate for a CE MRI screening test. Contrast-enhanced MRI might be a cost-effective screening modality for women at high risk, particularly for the BRCA1 and BRCA2 subgroups. Further work is needed to assess the impact of screening on mortality and health-related quality of life.
British Journal of Cancer 11/2006; 95(7):801-10. · 5.04 Impact Factor
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ABSTRACT: The aim of the study was to investigate whether pre-therapy vascular delivery assessment [using dynamic contrast enhanced magnetic resonance imaging (DCE-MRI)] can predict reduction in breast cancer metabolism [detected using 2-[(18)F] fluoro-2-deoxy-D-glucose positron emission tomography ((18)F(-)FDG-PET)] after a single cycle of chemotherapy. Reduction in (18)F-FDG PET metabolism has previously been shown to correlate with histological response to primary chemotherapy.
Seventeen patients with large or locally advanced invasive ductal carcinomas of the breast were imaged using DCE-MRI and (18)F-FDG-PET prior to therapy and 20 days after the first cycle of chemotherapy. MRI data were analysed using a multi-compartment model. PET data were analysed using standardised uptake value (SUV) analysis.
A significant association (P <0.05) was observed between pre-therapy DCE-MRI vascular parameters and the reduction in PET metabolism resulting from administration of one cycle of chemotherapy.
A relationship was demonstrated between pre-therapy DCE-MRI vascular parameters and the reduction in PET metabolism after a single cycle of chemotherapy. This suggests that reduction in PET metabolism as a result of chemotherapy may be dependent, at least in part, on pre-therapy vascular delivery. These pre-therapy vascular characteristics may be suitable for use as a surrogate measure for initial chemotherapy delivery, a key factor in chemotherapeutic efficacy.
Annals of Oncology 10/2006; 17(9):1393-8. · 6.43 Impact Factor
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ABSTRACT: Previous studies have indicated a relationship between bone mineral density and the incidence of breast cancer in middle-aged and elderly women, with women with higher BMD being at significant increased risk. We investigated whether there was such a relationship in younger women who were perimenopausal or in their early postmenopausal years. As part of a population-screening program for osteoporosis, 5,119 women aged between 45 and 54 years were scanned between 1990-1994 at the Osteoporosis Research Unit. In 1997-2001, 3,884 returned for follow-up scans and questionnaires, and 3,144 returned a postal questionnaire in 2002. All cases of incident breast cancer were noted. One hundred sixty-six women indicated that they had suffered from breast cancer, of which 87 were incident cases (59 had prevalent breast cancer at baseline and 20 had benign or unconfirmed diagnosis and were excluded because of the use of agents that may interfere with BMD, e.g., tamoxifen). We compared therefore the incident breast cancer group (BC group; n=87) with a control group (C group; n=3,013). There were no significant differences using a t-test between the BC group and C group for baseline DXA of the spine or femoral neck. Further changes in BMD over a mean period of 6.9 years demonstrated no significant hazard ratio for the lumbar spine or femoral neck. No relationship was seen between the bone turnover markers pyridinoline/creatinine or deoxypyridinoline/creatinine assessed at their second study visit and incidence of breast cancer. In conclusion, in perimenopausal or early postmenopausal women there is no relationship between the incidence of breast cancer and BMD, change in BMD or bone turnover.
Osteoporosis International 01/2006; 16(12):1627-32. · 4.58 Impact Factor
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ABSTRACT: Urgent endoscopy is indicated for suspected upper gastrointestinal malignancy. However, there is limited evidence on the age threshold for performing urgent endoscopy in uncomplicated dyspepsia (that is, without alarm features).
To quantify the risk of missing upper gastrointestinal malignancy within Scotland, if the age threshold for urgent endoscopy in uncomplicated dyspepsia was increased from 45 to 55 years.
Analysis of data collected prospectively by the Scottish Audit of Gastric and Oesophageal Cancer. 'Alarm' features at presentation were defined as dysphagia, weight loss, gastrointestinal bleeding, anaemia, vomiting, history of gastric surgery and history of peptic ulcer disease.
Of the 3293 patients diagnosed with upper gastrointestinal malignancy, 290 (8.8%) patients were <55 years of age. Twenty-one of the patients aged <55 years had no alarm features (0.64% of all patients); 12 were aged 45-55 years and nine were aged <45 years. Only two patients (one aged <45 years) underwent potentially curative surgery.
Upper gastrointestinal malignancy is uncommon under 55 years of age and most of the patients present with alarm features. Raising the age threshold for endoscopy for new-onset uncomplicated dyspepsia from 45 to 55 years would not impact adversely on the diagnosis or outcome of upper gastrointestinal malignancy.
Alimentary Pharmacology & Therapeutics 01/2006; 23(2):229-33. · 3.77 Impact Factor
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ABSTRACT: Complete surgical (R0) resection remains the only potentially curative intervention for patients with localised gastric cancer. To achieve a curative resection, patients may require complex operations with resection of contiguous organs. The aim of this study was to assess how the extent of surgical resection influenced morbidity, mortality and survival in an aged non-selected population with significant comorbid disease.
Data were extracted from the Scottish Audit of Gastric and Oesophageal Cancer (SAGOC), a prospective population-based audit of all oesophageal and gastric cancers in Scotland between 1997 and 1999 with a minimum of 1-year follow-up.
A total of 646 patients underwent surgical exploration for gastric cancer. A significantly higher incidence of chest infections (18.5 vs 11%, p< 0.05) and anastomotic leaks (14.3 vs 2.2%, p< 0.05) were associated with total gastrectomy (n=168) when compared to distal gastrectomy (n=272) resections. A 9.2% mortality rate and a 60% 1-year survival were associated with gastric resection alone. Removal of the spleen (n=131), pancreas (n=30) or liver resection (n=5) was associated with a significantly higher mortality rates, 18.3, 23.3 and 40%, respectively (p< 0.05), and significantly lower 1-year survival rates, 50.9, 39.1 and 20%, respectively (p< 0.05).
The risk of more extensive resection is not balanced by improved survival in this population based series. Extending gastric resection to involve contiguous organs should be confined to highly selected cases.
European Journal of Surgical Oncology 12/2005; 31(10):1141-4. · 2.50 Impact Factor
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F J Gilbert
Clinical Oncology 07/2005; 17(4):240-3. · 2.07 Impact Factor
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F J Gilbert
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ABSTRACT: Women with a strong family history of breast cancer are at increased risk of developing the disease themselves. Mammographic surveillance is recommended in the over 40 age group but the evidence of benefit from this strategy is limited until the individual reaches age 50 years. There is increasing evidence from the trials of breast magnetic resonance imaging that women at high risk may benefit from this technique as sensitivity is not dependent on breast density. The Dutch and Canadian studies have reported the sensitivity of MRI to be 71% and 77% compared to mammography which was 40% and 36%, respectively, in asymptomatic high risk cohorts.
Cancer Imaging 02/2005; 5(1):32-8. · 1.50 Impact Factor
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ABSTRACT: Under the auspices of the Scottish Audit of Gastric and Esophageal Cancer, we investigated treatment techniques, complications, and survival in a population-based cohort of patients undergoing endoscopic palliative therapy for esophageal or gastric cancer.
A total of 948 patients undergoing endoscopic palliative therapy were identified prospectively and followed for a minimum of 1 year.
Expandable metal stent placement (506 patients) and LASER (117 patients) were the most frequently used treatment options. Stent placement was more common for grade 3 or 4 dysphagia. Delivery of endoscopic palliative therapy varied by region of residence (from 18% to 38% of patients, p < 0.001) but not by deprivation category. Complications were recorded in 16% of patients (155 of 948). Overall survival was 40% (95% confidence interval [CI], 36-43) at 6 months, 17% (95% CI, 14-19) at 12 months, and 10% (95% CI, 8-12%) at 18 months.
These data define the reality of endoscopic palliative therapy for patients with advanced esophageal or gastric cancer and provide a baseline against which future improvements in care can be measured.
Surgical Endoscopy 08/2004; 18(8):1257-62. · 4.01 Impact Factor
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ABSTRACT: To establish whether the early use of sophisticated imaging techniques influences the clinical management and outcome of patients with low back pain (LBP) and whether it is cost-effective.
A pragmatic multicentre randomised controlled trial using a standard two parallel group approach incorporating an economic evaluation. For a subgroup of trial participants, a controlled 'before and after' approach was used to assess the impact of 'early imaging' on clinicians' diagnostic and therapeutic confidence.
A total of 782 participants who had been referred by their general practitioner to a consultant orthopaedic specialist or neurosurgeon because of symptomatic lumbar spine disorders. The study included 14 hospitals in Scotland and one in England over a 24-month period.
Participants in both groups reported an improvement in health status at 8 and 24 months with the 'early imaging' group having statistically significantly better outcome. Other than the proportion of participants receiving imaging (90% versus 30%), there were few differences between the groups in the management received throughout the 24-month follow-up. The total number of outpatient consultations in the two groups was similar although more people in the 'early imaging' group had return outpatient appointments during the 8-month follow-up. Clinicians' diagnostic confidence, between trial entry and follow-up, increased significantly for both groups with a greater increase in the 'early imaging' group. The cost of imaging was the main determinant of the difference in total costs between the groups and it was estimated that 'early imaging' could provide an additional 0.07 quality-adjusted life-years (QALYs), at an additional average cost of 61 British pounds over the 24-month follow-up. Using non-imputed costs and QALYs but adjusted for baseline differences in EQ-5D score, the mean incremental cost per QALY of 'early imaging' was 870 British pounds. The results were sensitive to the costs of imaging and the confidence intervals surrounding estimates of average costs and QALYs.
The early use of sophisticated imaging does not appear to affect management overall but does result in a slight improvement in clinical outcome at an estimated cost of 870 British pounds per QALY. Imaging was associated with an increase in clinicians' diagnostic confidence, particularly for non-specialists. Further research is required to determine if more rapid referral to sophisticated imaging and secondary care is important in the acute episode and whether the use of imaging would be more beneficial for particular categories of LBP.
Health technology assessment (Winchester, England) 06/2004; 8(17):iii, 1-131. · 4.26 Impact Factor
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ABSTRACT: To provide guidance on how to gather and evaluate evidence from the literature on the efficacy of imaging, using as an example the assessment of the role of magnetic resonance imaging (MRI) in the diagnosis of osteomyelitis. This method was adopted for evaluating evidence for the musculoskeletal section of the 5th edition of the Royal College of Radiologists' (RCR) guidelines.
A systematic review of the literature published between 1966 and July 2001 was carried out. Eligible articles described studies in patients with suspected osteomyelitis and who were diagnosed using MRI. Search strategies were developed to identify relevant imaging studies. Studies included in the systematic review were selected using predefined criteria. The sensitivity, specificity, accuracy and likelihood ratios for MRI reported in the studies were used to evaluate the value of the procedure in osteomyelitis. Where the above were not reported, they were calculated by the reviewers.
The average sensitivity of MRI in osteomyelitis was 91% (range 76-100%), the average specificity was 82% (range 65-96%), average accuracy was 88% (range 71-97%), and the average positive likelihood ratio was 7.8 (range 2.3-21.1). Four studies evaluated the use of MRI in the diagnosis of osteomyelitis in the diabetic foot, two in osteomyelitis of the lower extremities, while four each evaluated the use of MRI in vertebral osteomyelitis, in the diagnosis of any form of osteomyelitis, osteomyelitis in spinal cord-injured patients and in cranial osteomyelitis.
Systematic reviews of literature can be used to obtain evidence on the value of imaging procedures. The quality of the studies included in the review should always be considered when selecting studies to limit bias. In our example, MRI appears sensitive, specific and accurate in the diagnosis of osteomyelitis at different sites.
Clinical Radiology 02/2004; 59(1):63-8; discussion 62. · 1.95 Impact Factor
