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Dive into the research topics where Mehmet Sen is active.

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Featured researches published by Mehmet Sen.


Radiation Oncology | 2011

Recurrence patterns of locally advanced head and neck squamous cell carcinoma after 3D conformal (chemo)-radiotherapy

Didem Colpan Oksuz; Robin Prestwich; Brendan Carey; Stuart Wilson; Mustafa Senocak; Ananya Choudhury; K.E. Dyker; Catherine Coyle; Mehmet Sen

BackgroundTo establish recurrence patterns among locally advanced head and neck non-nasopharyngeal squamous cell carcinoma (HNSCC) patients treated with radical (chemo-) radiotherapy and to correlate the sites of loco-regional recurrence with radiotherapy doses and target volumesMethod151 locally advanced HNSCC patients were treated between 2004-2005 using radical three-dimensional conformal radiotherapy. Patients with prior surgery to the primary tumour site were excluded. The sites of locoregional relapses were correlated with radiotherapy plans by the radiologist and a planning dosimetrist.ResultsMedian age was 59 years (range:34-89). 35 patients had stage III disease, 116 patients had stage IV A/B. 36 patients were treated with radiotherapy alone, 42 with induction chemotherapy, 63 with induction and concomitant chemoradiotherapy and 10 concomitant chemoradiotherapy. Median follow-up was 38 months (range 3-62). 3-year cause specific survival was 66.8%. 125 of 151 (82.8%) achieved a complete response to treatment. Amongst these 125 there were 20 local-regional recurrence, comprising 8 local, 5 regional and 7 simultaneous local and regional; synchronous distant metastases occurred in 7 of the 20. 9 patients developed distant metastases in the absence of locoregional failure. For the 14 local recurrences with planning data available, 12 were in-field, 1 was marginal, and 1 was out-of-field. Of the 11 regional failures with planning data available, 7 were in-field, 1 was marginal and 3 were out-of-field recurrences.ConclusionThe majority of failures following non-surgical treatment for locally advanced HNSCC were loco-regional, within the radiotherapy target volume. Improving locoregional control remains a high priority.


Oral Oncology | 2012

Enteral feeding outcomes after chemoradiotherapy for oropharynx cancer: A role for a prophylactic gastrostomy?

Gillian F. Williams; Mark T.W. Teo; Mehmet Sen; K.E. Dyker; Catherine Coyle; Robin Prestwich

To determine the outcomes of patients managed with different routes of enteral feeding during chemoradiotherapy for oropharynx cancer. The hospital and dietetic records of consecutive patients with oropharynx squamous cell carcinoma treated between January 2007 and June 2009 with concurrent chemoradiotherapy were reviewed retrospectively. One hundred and four patients were analysed. Seventy-one received a prophylactic gastrostomy, 21 were managed with a strategy of NG tube as required and 12 received a therapeutic gastrostomy. Patients with a prophylactic gastrostomy commenced enteral feeding a median of 24 days after commencing radiotherapy, compared with a median of 41 days (p<0.001) for the NG as required group. Comparing prophylactic gastrostomy, NG as required and therapeutic gastrostomy, median number of unplanned inpatient days were 6, 14 and 7, respectively (p<0.01 for prophylactic gastrostomy vs. NG as required). Mean percentage weight loss at the end of treatment (6.1% vs. 7.1% vs. 5.2%, respectively) and at 6 months post-radiotherapy (11.7%, 14.3% and 8.9%) were similar in all groups (p=0.23). There was no significant difference in type of diet post-radiotherapy between prophylactic gastrostomy and NG as required groups (p=0.22). Median duration of enteral feeding was 181, 64 and 644 days, respectively (p<0.01 for prophylactic gastrostomy vs. NG as required). Use of a prophylactic gastrostomy (p<0.01) and higher T stage (p<0.01) were associated with increased duration of enteral feeding on a multivariate analysis. These data reinforce concerns regarding the detrimental impact of prophylactic gastrostomy placement upon long-term enteral feed dependence.


Tumori | 2004

Rapid tumor lysis syndrome in a patient with metastatic colon cancer as a complication of treatment with 5-fluorouracil/leucoverin and irinotecan

Ilhan Oztop; Binnaz Demirkan; Arzu Yaren; Oktay Tarhan; Bulent Sengul; Cagnur Ulukus; Davut Akin; Mehmet Sen; Ugur Yilmaz; Mehmet Alakavuklar

Tumor lysis syndrome is a potentially fatal complication of anticancer therapy that is usually seen in patients with bulky, rapidly proliferating, treatment-sensitive tumors such as hematological malignancies, but it rarely occurs in a variety of solid tumors such as colorectal carcinoma. Combination chemotherapy with infusional 5-fluorouracil/leucoverin and irinotecan has been recently accepted as the first treatment option for metastatic colorectal cancer. We present a case of tumor lysis syndrome in a patient with metastatic colon carcinoma that occurred 72 hrs after the initial course of a combination chemotherapy with irinotecan and 5-fluorouracil/leucoverin. Despite the immediate treatment with aggressive hydration by a sodium bicarbonate infusion, followed by forced diuresis and uricolytic therapy, he died of a sudden cardiac arrest complicated by acute renal failure. Our case indicates that administration of 5-fluorouracil/leucoverin and irinotecan for bulky tumors of colorectal origin with a rapid doubling time may induce an acute tumor lysis syndrome, which necessitates frequent laboratory monitoring and a close follow-up of the patient as well as prompt initiation of appropriate therapeutic measures.


Oral Oncology | 2013

Outcomes following chemoradiotherapy for N3 head and neck squamous cell carcinoma without a planned neck dissection.

Ebru Karakaya; Ozlem Yetmen; Didem Çolpan Öksüz; Karen E. Dyker; Catherine Coyle; Mehmet Sen; Robin Prestwich

OBJECTIVES The optimal management of the N3 neck in head and neck squamous cell carcinoma (HNSCC) remains controversial. We report the outcomes of patients with N3 disease treated with a strategy of concurrent chemo-radiotherapy (CRT)±induction chemotherapy (ICT) without a planned neck dissection. MATERIALS AND METHODS Forty patients with HNSCC N3 disease treated between January 2004 and December 2010 were retrospectively identified. Inclusion criteria for the study were: non-nasopharyngeal HNSCC, N3 nodal disease, intention to treat with CRT±ICT. RESULTS Median age was 60 (range 39-74). Median follow up was 32 months (range 8-88). 34 (85%) of patients received ICT. 35 patients received cisplatin-CRT, 4 carboplatin-CRT and 1 patient was treated with radiotherapy alone due to ICT toxicity. 27 (67.5%) patients had a complete response (CR) to CRT. 5 (12.5%) patients had an incomplete response in both the primary and nodal sites. 8 (20%) patients had a CR in the primary site but incomplete in the nodal regions. The crude rate of regional failure following a CR was 3/27 (11.2%). Isolated regional failure occurred in 1/27 (3.7%) patients who had achieved a CR post-CRT. 3 year overall survival, disease free survival, locoregional control, local control and regional control in the whole cohort were 51.4%, 49.6%, 65.7%, 77.3%, 69.3%, and in patients with a CR were 73.3%, 70.0%, 86.6%, 90.5% and 91.7% respectively. CONCLUSION Isolated regional nodal failure is rare following a complete response to CRT for N3 HNSCC managed without a planned neck dissection.


Radiotherapy and Oncology | 1999

Definitive radiotherapy for 114 cases of T3N0 glottic carcinoma: influence of dose-volume parameters on outcome.

James P Wylie; Mehmet Sen; R. Swindell; Andrew J Sykes; W. T. Farrington; Nicholas J Slevin

BACKGROUND AND PURPOSE Assuming that the dose-response curve for T3N0M0 glottic carcinoma is steep and that the rate of occult lymph node metastases is low, it should be possible to employ high biological tumour doses to modest target volumes and thereby maximise laryngeal control without compromising final neck control. Within the constraints of a retrospective study we aim to examine this policy with respect to local control, incidence of nodal relapse and late complications. MATERIALS AND METHODS One hundred and fourteen patients with T3N0M0 glottic carcinoma who received a 3-week schedule of radical radiotherapy between 1986 and 1994 were analysed. The median age was 67 years (range, 34-85 years) and the median follow-up for living patients was 4.8 years (1.9-8.9 years). There were no strict selection criteria for those patients treated with radiotherapy. RESULTS The 5-year overall survival was 54%. The 5-year local control with radiotherapy and the ultimate loco-regional control following salvage laryngectomy were 68 and 80%, respectively. Nine patients (8%) suffered a regional nodal relapse but only three of these (3% overall) occurred in the absence of local failure. Four patients (3.5%) developed serious late complications requiring surgical intervention (three received 55 Gy and one 52.5 Gy). CONCLUSIONS It is possible to employ maximum tolerable doses to specific target volumes and thereby exploit the dose response demonstrated and minimise major late effects. The use of modest target volumes resulted in only 3% of patients requiring surgery that might have been avoided had prophylactic neck irradiation been employed.


Clinical Medicine Insights: Oncology | 2014

The Prognostic Role of the Neutrophil-to-Lymphocyte Ratio in Oropharyngeal Carcinoma Treated with Chemoradiotherapy

Caroline A Young; L. Murray; Ebru Karakaya; Helene H Thygesen; Mehmet Sen; Robin Prestwich

Background The aim of the study is to investigate the prognostic role of pre-treatment of markers of the systemic inflammatory response (neutrophil-to-lymphocyte ratio (NLR), platelet-to-lymphocyte ratio (PLR), and albumin) in patients with oropharyngeal carcinoma treated with chemoradiotherapy. Methods A total of 251 patients with oropharyngeal squamous cell cancer treated with chemoradiotherapy between 2004 and 2010 were retrospectively identified. NLR, PLR, and albumin were recorded from baseline blood parameters. NLR threshold of >5 and PLR thresholds of ≤150, >150 and ≤300, and >300 were used for analysis. Results Median follow-up was 46 months (range 9–98). The 3 year overall survival, local control, regional control, and distant control were 70%, 85%, 87%, and 87%, respectively. On multivariate analysis, locoregional control was associated with T stage (HR 3.3 (95% CI 1.5–6.9), P = 0.002) and NLR (HR 2.1 (95% CI 1.1–3.9), P = 0.023). Overall survival was associated with T stage (HR 2.47 (95% CI 1.45–4.2), P = 0.001) and grade (HR 0.61 (95% CI 0.38–0.99), P = 0.048). PLR and albumin were not significantly associated with disease outcomes or survival. Conclusions The NLR is an independent prognostic factor for locoregional control in oropharyngeal cancer treated with chemoradiotherapy.


Radiation Oncology | 2015

Definitive hypofractionated radiotherapy for early glottic carcinoma: experience of 55Gy in 20 fractions

Ekin Ermiş; Mark T.W. Teo; Karen E. Dyker; Chris Fosker; Mehmet Sen; Robin Prestwich

IntroductionA wide variety of fractionation schedules have been employed for the treatment of early glottic cancer. The aim is to report our 10-year experience of using hypofractionated radiotherapy with 55Gy in 20 fractions at 2.75Gy per fraction.MethodsPatients treated between 2004 and 2013 with definitive radiotherapy to a dose of 55Gy in 20 fractions over 4 weeks for T1/2 N0 squamous cell carcinoma of the glottis were retrospectively identified. Patients with prior therapeutic minor surgery (eg. laser stripping, cordotomy) were included. The probabilities of local control, ultimate local control (including salvage surgery), regional control, cause specific survival (CSS) and overall survival (OS) were calculated.ResultsOne hundred thirty-two patients were identified. Median age was 65 years (range 33–89). Median follow up was 72 months (range 7–124). 50 (38 %), 18 (14 %) and 64 (48 %) of patients had T1a, T1b and T2 disease respectively. Five year local control and ultimate local control rates were: overall - 85.6 % and 97.3 % respectively, T1a - 91.8 % and 100 %, T1b - 81.6 and 93.8 %, and T2 - 80.9 % and 95.8 %. Five year regional control, CSS and OS rates were 95.4 %, 95.7 % and 78.8 % respectively. There were no significant associations of covariates (e.g. T-stage, extent of laryngeal extension, histological grade) with local control on univariate analysis. Only increasing age and transglottic extension in T2 disease were significantly associated with overall survival (both p <0.01). Second primary cancers developed in 17 % of patients. 13 (9.8 %) of patients required enteral tube feeding support during radiotherapy; no patients required long term enteral nutrition. One patient required a tracheostomy due to a non-functioning larynx on long term follow up.ConclusionsHypofractionated radiation therapy with a dose of 55Gy in 20 fractions for early stage glottic cancer provides high rates of local control with acceptable toxicity.


Oral Oncology | 2016

Impact of prophylactic gastrostomy or reactive NG tube upon patient-reported long term swallow function following chemoradiotherapy for oropharyngeal carcinoma: A matched pair analysis

Brinda Sethugavalar; Mark T.W. Teo; Catriona Buchan; Ekin Ermiş; Gillian F. Williams; Mehmet Sen; Robin Prestwich

OBJECTIVES The purpose of this matched pair analysis is to assess patient-reported long term swallow function following chemoradiotherapy for locally advanced oropharyngeal cancer in relation to the use of a prophylactic gastrostomy or reactive nasogastric (NG) tube. MATERIALS AND METHODS The MD Anderson Dysphagia Inventory (MDADI) was posted to 68 consecutive patients with stage III/IV oropharyngeal squamous cell carcinoma who had completed parotid sparing intensity modulated radiotherapy with concurrent chemotherapy between 2010 and 2012, had not required therapeutic enteral feeding prior to treatment, minimum 2years follow up post treatment, and who were disease free. 59/68 replies were received, and a matched pair analysis (matching for T and N stage) was performed for 52 patients, 26 managed with a prophylactic gastrostomy and 26 with an approach of an NG tube as needed. RESULTS There were no significant differences in patient demographics, pre-treatment diet and treatment factors between the two groups. Patient-reported swallowing function measured using the MDADI was superior for patients managed with an NG tube as required compared with a prophylactic gastrostomy: overall composite score 68.1 versus 59.4 (p=0.04), global score 67.7 versus 60 (p=0.04), emotional subscale 73.5 versus 60.4 (p<0.01), functional subscale 75.4 versus 61.7 (p<0.01), and physical subscale 59.6 versus 57.1 (p=0.38). CONCLUSIONS Compared with an approach of an NG tube as required, the use of a prophylactic gastrostomy was associated with inferior long term patient-reported long term swallow outcomes.


Oral Oncology | 2003

A prospective evaluation of early thyroid dysfunction on completion of neck radiotherapy

Mehmet Koc; Necdet Ünüvar; Rachel Cooper Sen; İlyas Capoglu; Mehmet Sen

The purpose of this study was to examine thyroid dysfunction in the early phase of radiotherapy to the head and neck region. Forty-seven patients receiving neck irradiation including the thyroid gland were included. Twenty-eight patients had undergone either a functional or radical neck dissection and in 19 patients radiotherapy was the primary treatment. Compared to the pre-treatment values, there was a significant fall in the TSH level at completion of radiotherapy in the non-operated patients and a non-significant fall in the operated patients. The TSH was also significantly lower in the non-operated group at the end of treatment compared to the operated group. There was a significant fall in the FT3 and significant higher in the FT4 at the end of radiotherapy for both groups. This study shows that even during completion of radiotherapy to the head and neck region changes in thyroid function were observed for both previously operated and non-operated patients.


The Journal of Nuclear Medicine | 2014

Qualitative 18F-FDG PET/CT Response Evaluation After Chemotherapy or Radiotherapy for Head and Neck Squamous Cell Carcinoma: Is There an Equivocal Group?

Robin Prestwich; Mehmet Sen; Andrew Scarsbrook

1. Graham MM. Ventilation–perfusion lung scanning: stuck in a rut? J Nucl Med. 2014;55:1395–1396. 2. Bajc M, Neilly JB, Miniati M, Schuemichen C, Meignan M, Jonson B. EANM guidelines for ventilation/perfusion scintigraphy: part 2. Algorithms and clinical considerations for diagnosis of pulmonary emboli with V/P(SPECT) and MDCT. Eur J Nucl Med Mol Imaging. 2009;36:1528–1538. 3. Collart JP, Roelants V, Vanpee D, et al. Is a lung perfusion scan obtained by using single photon emission computed tomography able to improve the radionuclide diagnosis of pulmonary embolism? Nucl Med Commun. 2002;23:1107–1113.

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Robin Prestwich

St James's University Hospital

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Mark T.W. Teo

St James's University Hospital

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Andrew Scarsbrook

Leeds Teaching Hospitals NHS Trust

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Catherine Coyle

St James's University Hospital

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S. Ramasamy

Leeds Teaching Hospitals NHS Trust

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Münir Kinay

Dokuz Eylül University

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