Lynda Wyld
University of Sheffield
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Featured researches published by Lynda Wyld.
British Journal of Cancer | 2007
Daniel Hind; Lynda Wyld; M. W. R. Reed
The published literature comparing surgery, with or without adjuvant endocrine therapy, with endocrine therapy alone in older women with operable breast cancer was systematically reviewed. The design used is Cochrane review. Randomised controlled trials retrieved from the Cochrane Breast Cancer Group Specialised Register on 29 June 2005. Eligible studies recruited women aged 70 years or over with operable breast cancer, fit for surgery under general anaesthia. The studies compared surgery (either mastectomy or wide local excision, with or without endocrine therapy) to endocrine therapy alone. Primary outcomes were overall survival (OS) and progression-free survival (PFS). Double data extraction and quality assessment were undertaken. Seven eligible trials were identified of which six had published time-to-event data. The quality of the allocation concealment was adequate in three studies and unclear in the remainder. In each case the endocrine therapy used was tamoxifen. When surgery alone was compared to endocrine therapy alone, there was no significant difference in OS (hazard ratio (HR) 0.98, 95% confidence interval (CI) 0.74–1.30, P=0.9), but a significant difference in PFS (HR 0.55, 95% CI 0.39–0.77, P=0.0006). When surgery with adjuvant endocrine therapy was compared to endocrine therapy alone, there was no significant difference in OS (HR 0.86, 95% CI 0.73–1.00, P=0.06), but a significant difference in PFS (HR 0.65 (95% CI 0.53–0.81, P=0.0001) for surgery plus endocrine therapy vs primary endocrine. The regimens have different side effect profiles with one study suggesting increased psychosocial morbidity at 3 months in the surgical arm, which resolves by 2 years. Primary endocrine therapy with tamoxifen is associated with inferior local disease control but non-inferior survival to surgery for breast cancer in older women. Trials are needed to evaluate appropriate selection criteria for its use in terms of patient co-morbidity and quality of life. Trials are needed to evaluate the clinical effectiveness of aromatase inhibitors as primary therapy for this population.
British Journal of Cancer | 2004
Lynda Wyld; D K Garg; Id Kumar; H Brown; M. W. R. Reed
Breast cancer-specific mortality is static in older women despite having fallen in younger age groups, possibly due to lack of screening and differences in treatment. This study compared stage and treatment between two cohorts of postmenopausal women (55–69 vs >70 years) in a single cancer network over 6 months. A total of 378 patients were studied (>70: N=167, 55–69 years: N=210). Older women presented with more advanced disease (>70: metastatic/locally advanced 12%, 55–69 years: 3%, P<0.01). Those with operable cancer had a worse prognosis (Nottingham Prognostic Index (NPI) >70: median NPI 4.4, 55–69 years: 4.25, P<0.03). These stage differences were partially explained by higher screening rates in the younger cohort. Primary endocrine therapy was used in 42% of older patients compared with 3% in the younger group (P<0.001). Older women with cancers suitable for breast conservation were more likely to choose mastectomy (>70: 57.5% mastectomy rate vs 55–69 years: 20.6%, P<0.01). Nodal surgery was less frequent in older patients (>70: 6.7% no nodal surgery, 55–69 years: 0.5%, P<0.01) and was more likely to be inadequate (>70: 10.7% <4 nodes excised, 55–69 years: 3.4%, P<0.02). In summary, older women presented with more advanced breast cancer, than younger postmenopausal women and were treated less comprehensively.
British Journal of Cancer | 2009
Peter Scriven; S Coulson; R Haines; Saba P. Balasubramanian; Simon S. Cross; Lynda Wyld
Introduction:The tumour microenvironment is hypoglycaemic, hypoxic and acidotic. This activates a stress signalling pathway: the unfolded protein response (UPR). The UPR is cytoprotective if the stressor is mild, but may initiate apoptosis if severe.Activation of the UPR in breast carcinoma is induced by microenvironmental stress such as glucose and oxygen deprivation, but may also be linked to oestrogen stimulation. It may be clinically significant as it may alter chemosensitivity to doxorubicin.Methods:395 human breast adenocarcinomas were immunohistochemically stained for UPR activation markers (glucose-regulated protein (GRP-78 and XBP-1). A model of UPR activation in vitro by glucose deprivation of T47D breast cancer cells was developed to determine how the UPR affects cellular sensitivity to doxorubicin and 5-fluorouracil. Cytotoxicity was assessed using a colorimetric cytotoxicity assay (MTT). The effect of oestrogen stimulation and tamoxifen exposure on UPR activation by T47D cells was determined by western blotting measurement of the key UPR protein, GRP-78.Results:Expression of GRP78 and XBP-1 was demonstrated in 76% and 90% of the breast cancers, respectively, and correlated with oestrogen receptor positivity (P=0.045 and 0.017, respectively). In vitro UPR activation induced resistance to both doxorubicin and 5-flurouracil, (P<0.05). Oestrogen stimulation induced GRP78 and XBP1 over-expression on western blotting. Tamoxifen did not block this response and may induce UPR activation in its own right.Conclusions:The UPR is activated in the majority of breast cancers and confers resistance to chemotherapy. In vitro oestrogen stimulates UPR induction. UPR activation may contribute to breast cancer chemoresistance and interact with oestrogen response elements.
Ejso | 2011
Katy Cooper; S Harnan; Yang Meng; Sue Ward; Patrick Fitzgerald; Diana Papaioannou; Lynda Wyld; C. Ingram; Iain D. Wilkinson; E. Lorenz
PURPOSE Sentinel lymph node biopsy (SLNB) and axillary lymph node dissection (ALND) are used to assess axillary nodal status in breast cancer, but are invasive procedures associated with morbidity, including lymphoedema. This systematic review evaluates the diagnostic accuracy of positron emission tomography (PET), with or without computed tomography (CT), for assessment of axillary nodes in early breast cancer. METHODS Eleven databases including MEDLINE, EMBASE and the Cochrane Library, plus research registers and conference proceedings, were searched in April 2009. Study quality was assessed using the QUality Assessment of Diagnostic Accuracy Studies (QUADAS) checklist. Sensitivity and specificity were meta-analysed using a bivariate random effects approach. RESULTS Across 26 studies evaluating PET or PET/CT (n = 2591 patients), mean sensitivity was 63% (95% CI: 52-74%; range 20-100%) and mean specificity 94% (95% CI: 91-96%; range 75-100%). Across 7 studies of PET/CT (n = 862), mean sensitivity was 56% (95% CI: 44-67%) and mean specificity 96% (90-99%). Across 19 studies of PET-only (n = 1729), mean sensitivity was 66% (50-79%) and mean specificity 93% (89-96%). Mean sensitivity was 11% (5-22%) for micrometastases (≤2 mm; five studies; n = 63), and 57% (47-66%) for macrometastases (>2 mm; four studies; n = 111). CONCLUSIONS PET had lower sensitivity and specificity than SLNB. Therefore, replacing SLNB with PET would avoid the adverse effects of SLNB, but lead to more false negative patients at risk of recurrence and more false positive patients undergoing unnecessary ALND. The present evidence does not support the routine use of PET or PET-CT for the assessment of the clinically negative axilla.
British Journal of Cancer | 1998
Lynda Wyld; M. W. R. Reed; Nicola J. Brown
Photodynamic therapy (PDT) is a cancer treatment based on the interaction of light and a photosensitizing chemical. The photosensitizer protoporphyrin IX (PpIX) is generated via the haem biosynthetic pathway after administration of aminolaevulinic acid (ALA). The cellular microenvironment of tumours is hypoxic and acidotic relative to normal tissue, which may influence PpIX generation and compromise PDT efficacy. This study used bladder cancer cells, incubated with ALA at various oxygen tensions and H+ ion concentrations, and assessed the effects on PpIX generation and PDT sensitivity. PpIX production was reduced at 0%, 2.5% (19 mmHg) and 5% (38 mmHg) oxygen compared with that at 21% (160 mmHg) oxygen (0.15, 0.28 and 0.398 ng microg(-1) protein compared with 0.68 ng microg(-1) respectively; P < 0.05). The response to PDT was abolished by hypoxia, as a result of both reduced PpIX synthesis and reduced PDT toxicity. PpIX production was greater at pH 7.0 and 6.5 (0.75 and 0.66 ng microg(-1)) compared with that at pH 7.4 and 5.5 (0.41 and 0.55 ng microg(-1) respectively). PDT cytotoxicity was enhanced at lower pH values. These results suggest that ALA-induced PDT may be inhibited by hypoxia due to reduced intrinsic PpIX synthesis. Acidosis may slightly enhance the efficacy of ALA-induced PDT.
British Journal of Cancer | 1997
Lynda Wyld; J. L. Burn; M. W. R. Reed; Nicola J. Brown
Photodynamic therapy (PDT) may cause tumour cell destruction by direct toxicity or by inducing cellular hypoxia as a result of microcirculatory shutdown. Aminolaevulinic acid (ALA) causes cellular accumulation of protoporphyrin IX (PPIX) in cells exposed to it in excess. PPIX can be used as a photosensitizer for PDT. Microcirculatory shutdown may be induced by toxicity to the endothelial and vascular smooth muscle (VSM) cells or by release of vasoactive substances. We have studied whether PPIX is produced by endothelial, VSM and tumour cells on exposure to ALA and whether these cell lines are directly damaged by PDT in vitro. Tumour endothelial cells are angiogenic and we have, therefore, investigated the effect of cellular proliferation rates on PPIX generation. Tumour cells generate more PPIX intracellularly than the non-neoplastic cell lines studied and are correspondingly more sensitive to PDT-induced cytotoxicity. Endothelial cells are sensitive to PDT-induced cytotoxicity and accumulate between 1.5 and four times more PPIX when proliferating (as during tumour-induced angiogenesis) than when quiescent. We conclude that PPIX-mediated PDT may exert some of its effects on the microcirculation of treated tissues by direct toxicity to endothelial and VSM cells, and that this toxicity may be enhanced in the tumour microenvironment.
Ejso | 2011
S Harnan; Katy Cooper; Yang Meng; Sue Ward; Patrick Fitzgerald; Diana Papaioannou; C. Ingram; E. Lorenz; Iain D. Wilkinson; Lynda Wyld
INTRODUCTION Current methods of identifying axillary node metastases in breast cancer patients are highly accurate, but are associated with several adverse events. This review evaluates the diagnostic accuracy of magnetic resonance imaging (MRI) techniques for identification of axillary metastases in early stage newly diagnosed breast cancer patients. METHODS Comprehensive searches were conducted in April 2009. Study quality was assessed. Sensitivity and specificity were meta-analysed using a bivariate random effects approach, utilising pathological diagnosis via node biopsy as the comparative gold standard. RESULTS Based on the highest sensitivity and specificity reported in each of the nine studies evaluating MRI (n = 307 patients), mean sensitivity was 90% (95% CI: 78-96%; range 65-100%) and mean specificity 90% (95% CI: 75-96%; range 54-100%). Across five studies evaluating ultrasmall super-paramagnetic iron oxide (USPIO)-enhanced MRI (n = 93), mean sensitivity was 98% (95% CI: 61-100%) and mean specificity 96% (95% CI: 72-100%). Across three studies of gadolinium-enhanced MRI (n = 187), mean sensitivity was 88% (95% CI: 78-94%) and mean specificity 73% (95% CI: 63-81%). In the single study of in-vivo proton MR spectroscopy (n = 27), sensitivity was 65% (95% CI: 38-86%) and specificity 100% (95% CI: 69-100%). CONCLUSIONS USPIO-enhanced MRI showed a trend towards higher sensitivity and specificity and may make a useful addition to the current diagnostic pathway. Additional larger studies with standardised methods and standardised criteria for classifying a node as positive are needed. Current estimates of sensitivity and specificity do not support replacement of SLNB with any current MRI technology in this patient group.
Health Technology Assessment | 2011
Katy Cooper; Yang Meng; S Harnan; Sue Ward; Patrick Fitzgerald; Diana Papaioannou; Lynda Wyld; Christine E. Ingram; Iain D. Wilkinson; E. Lorenz
BACKGROUND Breast cancer is the most common type of cancer in women. Evaluation of axillary lymph node metastases is important for breast cancer staging and treatment planning. OBJECTIVES To evaluate the diagnostic accuracy, cost-effectiveness and effect on patient outcomes of positron emission tomography (PET), with or without computed tomography (CT), and magnetic resonance imaging (MRI) in the evaluation of axillary lymph node metastases in patients with newly diagnosed early-stage breast cancer. DATA SOURCES A systematic review of literature and an economic evaluation were carried out. Key databases (including MEDLINE, EMBASE and nine others) plus research registers and conference proceedings were searched for relevant studies up to April 2009. A decision-analytical model was developed to determine cost-effectiveness in the UK. REVIEW METHODS One reviewer assessed titles and abstracts of studies identified by the search strategy, obtained the full text of relevant papers and screened them against inclusion criteria. Data from included studies were extracted by one reviewer using a standardised data extraction form and checked by a second reviewer. Discrepancies were resolved by discussion. Quality of included studies was assessed using the quality assessment of diagnostic accuracy studies (QUADAS) checklist, applied by one reviewer and checked by a second. RESULTS Forty-five citations relating to 35 studies were included in the clinical effectiveness review: 26 studies of PET and nine studies of MRI. Two studies were included in the cost-effectiveness review: one of PET and one of MRI. Of the seven studies evaluating PET/CT (n = 862), the mean sensitivity was 56% [95% confidence interval (CI) 44% to 67%] and mean specificity 96% (95% CI 90% to 99%). Of the 19 studies evaluating PET only (n = 1729), the mean sensitivity was 66% (95% CI 50% to 79%) and mean specificity 93% (95% CI 89% to 96%). PET performed less well for small metastases; the mean sensitivity was 11% (95% CI 5% to 22%) for micrometastases (≤ 2 mm; five studies; n = 63), and 57% (95% CI 47% to 66%) for macrometastases (> 2 mm; four studies; n = 111). The smallest metastatic nodes detected by PET measured 3 mm, while PET failed to detect some nodes measuring > 15 mm. Studies in which all patients were clinically node negative showed a trend towards lower sensitivity of PET compared with studies with a mixed population. Across five studies evaluating ultrasmall super-paramagnetic iron oxide (USPIO)-enhanced MRI (n = 93), the mean sensitivity was 98% (95% CI 61% to 100%) and mean specificity 96% (95% CI 72% to 100%). Across three studies of gadolinium-enhanced MRI (n = 187), the mean sensitivity was 88% (95% CI 78% to 94%) and mean specificity 73% (95% CI 63% to 81%). In the single study of in vivo proton magnetic resonance spectroscopy (n = 27), the sensitivity was 65% (95% CI 38% to 86%) and specificity 100% (95% CI 69% to 100%). USPIO-enhanced MRI showed a trend towards higher sensitivity and specificity than gadolinium-enhanced MRI. Results of the decision modelling suggest that the MRI replacement strategy is the most cost-effective strategy and dominates the baseline 4-node sampling (4-NS) and sentinel lymph node biopsy (SLNB) strategies in most sensitivity analyses undertaken. The PET replacement strategy is not as robust as the MRI replacement strategy, as its cost-effectiveness is significantly affected by the utility decrement for lymphoedema and the probability of relapse for false-negative (FN) patients. LIMITATIONS No included studies directly compared PET and MRI. CONCLUSIONS Studies demonstrated that PET and MRI have lower sensitivity and specificity than SLNB and 4-NS but are associated with fewer adverse events. Included studies indicated a significantly higher mean sensitivity for MRI than for PET, with USPIO-enhanced MRI providing the highest sensitivity. However, sensitivity and specificity of PET and MRI varied widely between studies, and MRI studies were relatively small and varied in their methods; therefore, results should be interpreted with caution. Decision modelling based on these results suggests that the most cost-effective strategy may be MRI rather than SLNB or 4-NS. This strategy reduces costs and increases quality-adjusted life-years (QALYs) because there are fewer adverse events for the majority of patients. However, this strategy leads to more FN cases at higher risk of cancer recurrence and more false- positive (FP) cases who would undergo unnecessary axillary lymph node dissection. Adding MRI prior to SLNB or 4-NS has little effect on QALYs, though this analysis is limited by lack of available data. Future research should include large, well-conducted studies of MRI, particularly using USPIO; data on the long-term impacts of lymphoedema on cost and patient utility; studies of the comparative effectiveness and cost-effectiveness of SLNB and 4-NS; and more robust UK cost data for 4-NS and SLNB as well as the cost of MRI and PET techniques. FUNDING This study was funded by the Health Technology Assessment programme of the National Institute of Health Research.
British Journal of Surgery | 2003
Lynda Wyld; Malcolm Reed
Breast cancer is a major source of morbidity and mortality in elderly women. Despite this, many trials on which clinical practice is based have under‐represented the elderly. Consequently there is little evidence to guide best practice in this age group.
European Journal of Gastroenterology & Hepatology | 2010
Feras Y. Al-Rawashdeh; Peter Scriven; Ian C. Cameron; Patricia V. Vergani; Lynda Wyld
Objective Hepatocellular carcinoma (HCC) has an annual worldwide incidence of 626 000 cases and causes 550 000 deaths per year. Although the mainstay of treatment is surgical resection, for inoperable or metastatic disease, chemotherapy may be offered. The primary agent used is doxorubicin, but response rates are poor (<20%). The unfolded protein response (UPR) is a cytoprotective cellular stress response that enables cells to survive periods of hypoxia and nutrient deprivation. The UPR may confer resistance to anticancer agents and contribute to treatment failure. This study has investigated whether the UPR is activated in HCC and whether this may contribute to doxorubicin resistance. Methods Eighty-six human HCCs were immunohistochemically stained for glucose regulated protein 78, the key marker of UPR activation. An in-vitro model of UPR activation in HepG2 HCC cells was developed by glucose deprived culture. UPR activation was confirmed with western blotting and PCR to show overexpression of glucose regulated protein 78. The relative efficacy of doxorubicin chemotherapy on UPR-activated HepG2 cells was compared with normal HepG2 cells by use of an thiazolyl blue tetrazolium bromide colorimetric assay. Results Expression of glucose regulated protein 78 was shown in 100% of the HCC samples with 66% showing strong staining. In-vitro UPR activation was achieved with glucose deprivation. UPR activation induced significant resistance to doxorubicin: 34% survival under standard culture conditions versus 58% and 63% for UPR-activated cells in 0.5 and 1 mmol glucose respectively (P=0.00928). Conclusion The UPR is activated in HCCs and confers resistance to chemotherapy in vitro. UPR activation may contribute to HCC chemoresistance.