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Dive into the research topics where Constantinos Yiangou is active.

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Featured researches published by Constantinos Yiangou.


BMC Cancer | 2005

Cancer cell adaptation to chemotherapy.

Federica Di Nicolantonio; Stuart Mercer; Louise A. Knight; Francis G. Gabriel; Pauline A. Whitehouse; Sanjay Sharma; Augusta Fernando; Sharon Glaysher; Silvana Di Palma; Penny Johnson; Shaw Somers; Simon Toh; Bernard Higgins; Alan Lamont; Tim J Gulliford; Jeremy Hurren; Constantinos Yiangou; Ian A. Cree

BackgroundTumor resistance to chemotherapy may be present at the beginning of treatment, develop during treatment, or become apparent on re-treatment of the patient. The mechanisms involved are usually inferred from experiments with cell lines, as studies in tumor-derived cells are difficult. Studies of human tumors show that cells adapt to chemotherapy, but it has been largely assumed that clonal selection leads to the resistance of recurrent tumors.MethodsCells derived from 47 tumors of breast, ovarian, esophageal, and colorectal origin and 16 paired esophageal biopsies were exposed to anticancer agents (cisplatin; 5-fluorouracil; epirubicin; doxorubicin; paclitaxel; irinotecan and topotecan) in short-term cell culture (6 days). Real-time quantitative PCR was used to measure up- or down-regulation of 16 different resistance/target genes, and when tissue was available, immunohistochemistry was used to assess the protein levels.ResultsIn 8/16 paired esophageal biopsies, there was an increase in the expression of multi-drug resistance gene 1 (MDR1) following epirubicin + cisplatin + 5-fluorouracil (ECF) chemotherapy and this was accompanied by increased expression of the MDR-1 encoded protein, P-gp. Following exposure to doxorubicin in vitro, 13/14 breast carcinomas and 9/12 ovarian carcinomas showed >2-fold down-regulation of topoisomerase IIα (TOPOIIα). Exposure to topotecan in vitro, resulted in >4-fold down-regulation of TOPOIIα in 6/7 colorectal tumors and 8/10 ovarian tumors.ConclusionThis study suggests that up-regulation of resistance genes or down-regulation in target genes may occur rapidly in human solid tumors, within days of the start of treatment, and that similar changes are present in pre- and post-chemotherapy biopsy material. The molecular processes used by each tumor appear to be linked to the drug used, but there is also heterogeneity between individual tumors, even those with the same histological type, in the pattern and magnitude of response to the same drugs. Adaptation to chemotherapy may explain why prediction of resistance mechanisms is difficult on the basis of tumor type alone or individual markers, and suggests that more complex predictive methods are required to improve the response rates to chemotherapy.


European Journal of Oncology Nursing | 2009

Breast cancer follow up: a randomised controlled trial comparing point of need access versus routine 6-monthly clinical review.

C. Sheppard; Bernard Higgins; M. Wise; Constantinos Yiangou; D. Dubois; Sally Kilburn

AIM To examine a model of care for breast cancer patients based on the concept of point of need access and investigate the effectiveness of this model compared to routine 6-monthly clinical reviews. DESIGN A parallel randomised controlled trial was used to examine point of need access to specialist care via the nurse specialist, compared to routine hospital based 6-monthly clinical review at year two post breast cancer diagnosis. A total of 237 patients were recruited to the study. METHODS Outcome measures at baseline, 9 and 18 months included psychological morbidity using the GHQ12 questionnaire, quality of life using the FACT-B plus endocrine subscale, fear and isolation. An analysis of covariance was used to detect changes over time. Recurrences and methods of detection were recorded as secondary outcome measures. RESULTS Two hundred and fourteen patients completed the study. Overall patients were not exposed to risks of increased psychological morbidity (p=0.767) or decline of quality of life (p=0.282) when routine review was discontinued and no significant differences were detected during an 18-month period. Patients not receiving regular review did not feel isolated, and at the end of 18 months did not wish to return to 6-monthly clinical reviews. The presentation of recurrences and short symptom history demonstrate that the recurrences observed were unlikely to have been detected at a routine visit. CONCLUSIONS Point of need access is acceptable to the majority of patients. Although a third of patients may wish to maintain a regular review, patient choice is important. Findings suggest that after 2 years following the diagnosis of breast cancer there is no evidence to support the view that regular clinical review improves psychological morbidity or quality of life. Patients do not appear to be compromised in terms of early detection of recurrence. Point of need access can be provided by suitably trained specialist nurses and provides a fast, responsive management system at a time when patients really need it.


Journal of Clinical Pathology | 2010

Observational and cost analysis of the implementation of breast cancer sentinel node intraoperative molecular diagnosis

Ramsey I. Cutress; Amanda McDowell; Francis G. Gabriel; J. Gill; M. J. Jeffrey; Avi Agrawal; M. Wise; J. Raftery; Ian A Cree; Constantinos Yiangou

Background Accurate intraoperative sentinel lymph node (SLN) assessment enables axillary clearance to be completed immediately in node-positive breast cancer patients. This article reports a study of the introduction of intraoperative molecular SLN analysis in routine clinical practice in the Portsmouth Breast Care Centre. Design There was prospective analysis of 254 consecutive patients who underwent SLN biopsy in a single centre. Nodes were sectioned at 2 mm intervals and alternate slices were analysed using a CE-marked assay for mammaglobin (MG) and cytokeratin 19 (CK19). Remaining slices of node were sent for histological analysis, which included CK19 immunohistochemistry. While the assay was being carried out, the surgeon performed the breast tumour resection. The cost per patient was estimated retrospectively and the cost effects on the hospital and primary care trust for a typical service were also estimated. Results A total of 491 SLNs from 254 patients were evaluated. The intraoperative assay showed positivity of SLNs for metastatic cells in 78 patients. There was 100% detection of macrometastases within sentinel nodes analysed by GeneSearch. Overall concordance between histological status, including micrometastases and GeneSearch analysis, was 95% (sensitivity 96%, specificity 95%). The cost per procedure was increased for wide local excision with SLN biopsy and intraoperative assessment compared with other models, but fewer procedures were carried out. Conclusion Intraoperative assessment of SLNs in breast cancer using a molecular assay is a safe, acceptable and accurate technique that allows a reduction in the frequency of delayed axillary clearance surgery. Take-up of this method may be hampered by perverse incentives operating within healthcare funding.


The Breast | 2012

The effect of introducing an in-theatre intra-operative specimen radiography (IOSR) system on the management of palpable breast cancer within a single unit

David Layfield; D.J. May; Ramsey I. Cutress; C. Richardson; Avi Agrawal; M. Wise; Constantinos Yiangou

INTRODUCTION Intra-operative specimen radiography (IOSR) is used to screen specimens during breast-conserving surgery and attempt to identify incompletely excised lesions. Universal use of IOSR during surgery for impalpable breast cancer is advocated by current guidelines. This study evaluates the role of IOSR during breast-conserving surgery for palpable breast cancer. METHODS Two cohorts of patients who underwent wide local excision for palpable breast cancer were identified. Retrospective analysis of histological margins, intra-operative cavity shaves, secondary re-excision rates and specimen weight was completed comparing performance prior to the introduction of IOSR (October 2003-April 2005) with that since its introduction (April 2006-October 2007). RESULTS 224 Patients were included, 111 in the pre-IOSR cohort (PF) and 113 in the IOSR cohort (F). Patient demographics, tumour size and histology were comparable. No difference in margin involvement prior to intra-operative cavity shaving was noted, PF-26, F-31 (p=0.60). Intra-operative cavity shaves were carried out more frequently in the IOSR group, PF-9, F-32 (p=0.001). When compared with histological findings, IOSR identified margin compromise with sensitivity=58.1%, specificity=80.8%, positive-predictive value=56.25% and negative predictive value=81.9%. Re-operation rate was similar between the 2 groups, PF-26, F-31 (p=0.65). Significantly less tissue was excised following use of IOSR; PF-110g, F-70g (p=0.001). CONCLUSION Introduction of IOSR significantly reduced specimen weights without increasing re-excision rates. As volume of breast tissue removed is the most significant determinant of cosmetic outcome following breast-conserving surgery, the use of IOSR should be advocated in the surgical management of palpable breast cancer.


Journal of Clinical Pathology | 2014

BRAF V600 co-testing in thyroid FNA cytology: short-term experience in a large cancer centre in the UK

David Poller; Sharon Glaysher; Avi Agrawal; Saliya Caldera; Dae Kim; Constantinos Yiangou

Aims To ascertain whether BRAF V600 mutational analysis is useful for diagnosis of thyroid cancer in thyroid fine needle aspirate (FNA). Methods Over 8 months thyroid FNAs reported as Thy 3F (neoplasm possible/suggestive of follicular neoplasm), Thy4 (suspicious of malignancy) and Thy 5 (malignant) were tested for BRAF V600 mutation and managed as malignant if mutations were present. Results Of 207 FNAs from 176 patients, 5 were Thy 5, 19 Thy 4, 36 Thy 3f, 13 Thy 3a, 84 Thy 2 and 50 Thy 1. 11 Thy 3f, 15 Thy 4 and 3 Thy 5 FNAs were tested for BRAF V600 mutation. 0 Thy 3F cases, 6 Thy 4 and 1 Thy 5 (24% of the total tested) showed evidence of mutation. Four patients with BRAF V600 mutation underwent surgery to remove all thyroid tissue, two patients received a lobectomy and one patient is awaiting thyroidectomy. All patients with BRAF V600 mutation were found to have malignancy on final histology, with a diagnostic sensitivity for malignancy excluding coincidental microcarcinoma of 43% and specificity of 100%. Conclusions BRAF V600 mutational analysis can enable single-stage total thyroidectomy for carcinoma if gene mutation is present in preoperative FNA. BRAF V600 co-testing may reduce the need for completion thyroidectomy with implied cost savings and lower patient morbidity associated with completion thyroidectomy when the cytology is inconclusive but where BRAF V600 mutation is identified in preoperative thyroid FNA.


Surgeon-journal of The Royal Colleges of Surgeons of Edinburgh and Ireland | 2013

Repeat surgery following breast conservation and intra-operative sentinel lymph node analysis for breast cancer

Natalie Dabbas; Ramsey I. Cutress; M. Wise; Constantinos Yiangou; Avi Agrawal

INTRODUCTION Intra-operative sentinel node analysis (IOA) for breast cancer reduces the need for a second operation by revealing metastasis intra-operatively, allowing immediate axillary clearance. Critics argue that the number of patients deriving benefit is limited, as further surgery is often required for reasons other than nodal status. AIM To identify the proportion of women avoiding further surgery by using IOA excluding those who require further surgery for reasons other than axillary node metastasis. PATIENTS AND METHODS All patients undergoing sentinel node biopsy with IOA over one year were reviewed. Patient demographics, margin positivity, sentinel node metastasis, requirement for further surgery, and cavity shave involvement were analysed. RESULTS 322 patients were analysed: 253 undergoing breast-conserving surgery [BCS] and 69 undergoing mastectomy). IOA revealed metastasis in 81 (25.2.%) patients [25 undergoing mastectomy and 56 undergoing BCS], who underwent immediate axillary clearance. 43 BCS patients (17%) did not require further surgery other than for sentinel node involvement. 39 patients required further oncological surgery: 16 excision of margins; 13 completion mastectomy; 6 excision of margins followed by mastectomy; 3 completion axillary clearance; and 1 excision of recurrence. 20.6% had involvement of any circumferential histological margin. Cavity shaves were performed in 28.5% patients at initial surgery, the majority of which were clear of malignancy. 20 mastectomy patients had concordant definitive histology, avoiding a second operation. In total, 19.6% of this cohort avoided a second operation through the use of IOA. DISCUSSION Approximately 15% of patients undergoing breast conservation surgery for breast cancer require further surgery. However, a further 17% were saved subsequent surgery by utilising IOA, since they had immediate axillary clearance. When also considering patients undergoing mastectomy, this proportion is even higher.


Ejc Supplements | 2004

Sentinel lymph node biopsy in male breast cancer patients

Amit Goyal; K. Horgan; M.W. Kissin; Constantinos Yiangou; Mark Sibbering; M. Lansdown; Robert G. Newcombe; Robert E. Mansel; U. Chetty; P. Ell; Lesley Fallowfield

The concept of sentinel node biopsy has been validated for female breast cancer patients whereas, ALND remains the standard of care for male breast cancer patients with similar tumours. We evaluated the results of SLN biopsy in male breast cancer patients with clinically negative axillae. This study included all male breast cancer patients who underwent SLN biopsy between February 1998 and October 2003. All patients had negative axillae on clinical examination. All patients underwent pre-operative lymphoscintigraphy. SLN biopsy was performed using a combination of Patent blue V and 99mTc-radiolabelled colloidal albumin injected peritumourally. Nine patients, 26-79 years of age, were included in the study. Pre-operative lymphoscinitgraphy identified SLNs in all patients. Intraoperatively, SLNs were successfully localised in all patients. The mean number of SLNs encountered was 2.4. Five patients had a positive SLN, four a negative SLN. Five patients (one with a negative SLN, four with a positive SLN) had been elected pre-operatively to undergo ALND regardless of findings on SLN biopsy. ALND confirmed the SLN to be negative in one patient (false-negative rate: 0%) and three of the four patients with positive SLN(s) had additional positive nodes in the axilla. SLN biopsy accurately predicted axillary lymph node status in these five patients. These findings compare favourably with findings reported in the literature regarding SLN biopsy in female breast cancer patients. SLN biopsy accurately staged the axilla in male breast cancer patients and should be considered for axillary staging in male breast cancer patients with clinically negative axillae.


International journal of breast cancer | 2012

The Axillary Nodal Harvest in Breast Cancer Surgery Is Unchanged by Sentinel Node Biopsy or the Timing of Surgery

Ben E. Byrne; Ramsey I. Cutress; J. Gill; M. Wise; Constantinos Yiangou; Avi Agrawal

Introduction. Patients with a positive sentinel lymph node biopsy may undergo delayed completion axillary dissection. Where intraoperative analysis is available, immediate completion axillary dissection can be performed. Alternatively, patients may undergo primary axillary dissection for breast cancer, historically or when preoperative assessment suggests axillary metastases. This study aims to determine if there is a difference in the total number of lymph nodes or the number of metastatic nodes harvested between the 3 possible approaches. Methods. Three consecutive comparable groups of 50 consecutive patients who underwent axillary dissection in each of the above contexts were identified from the Portsmouth Breast Unit Database. Patient demographics, clinicopathological variables, and surgical treatment were recorded. The total pathological nodal count and the number of metastatic nodes were compared between the groups. Results. There were no differences in clinico-pathological features between the three groups for all features studied with the exception of breast surgical procedure (P < 0.001). There were no differences in total nodal harvest (P = 0.822) or in the number of positive nodes harvested (P = 0.157) between the three groups. Conclusion. The three approaches to axillary clearance yield equivalent nodal harvests, suggesting oncological equivalence and robustness of surgical technique.


Ejso | 2004

Sentinel lymph node biopsy in male breast cancer patients.

Amit Goyal; Kieran Horgan; M.W. Kissin; Constantinos Yiangou; M. Sibbering; M. Lansdown; Robert G. Newcombe; Robert E. Mansel


Ejso | 2006

Radiological review of specimen radiographs after breast localisation biopsy is not always necessary

N.J. Coombs; P.P. Vassallo; A.J. Parker; Constantinos Yiangou

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Avi Agrawal

Queen Alexandra Hospital

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M. Wise

Queen Alexandra Hospital

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Lucy Mansfield

Queen Alexandra Hospital

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Sophie Helme

Queen Alexandra Hospital

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I. Cree

Queen Alexandra Hospital

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Victoria Brown

Queen Alexandra Hospital

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Albert Ngu

Queen Alexandra Hospital

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Guy Gabriel

Queen Alexandra Hospital

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