Athens, Greece
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PubMed | Venizelio Hospital, 251 General Air Force Hospital, Mitera Hospital, General Hospital of Chania and 6 more.
Type: Journal Article | Journal: Clinical genitourinary cancer | Year: 2016

Advanced urothelial cancer (AUCa) is associated with poor long-term survival. Two major concerns are related to nonexposure to cisplatin-based chemotherapy and poor outcome after relapse. Our purpose was to record patterns of practice in AUCa in Greece, focusing on first-line treatment and management of relapsed disease.Patients with AUCa treated from 2011 to 2013 were included in the analysis. Fitness for cisplatin was assessed by recently established criteria.Of 327 patients treated with first-line chemotherapy, 179 (55%) did not receive cisplatin. Criteria for unfitness for cisplatin were: Eastern Cooperative Oncology Group (ECOG) performance status (PS) 2, 21%; creatinine clearance 60 mL/min, 55%; hearing impairment, 8%; neuropathy, 1%; and cardiac failure, 5%. Forty-six patients (27%) did not fulfill any criterion for unfitness for cisplatin. The main reasons for these deviations were comorbidities (28%) and advanced age (32%). Seventy-four (68%) of 109 patients who experienced a relapse received second-line chemotherapy. The most frequent reason for not offering second-line chemotherapy was poor PS or limited life expectancy (66%).In line with international data, approximately 50% of Greek patients with AUCa do not receive cisplatin-based chemotherapy, although 27% of them were suitable for such treatment. In addition, about one third of patients with relapse did not receive second-line chemotherapy because of poor PS or short life expectancy. Enforcing criteria for fitness for cisplatin and earlier diagnosis of relapse represent 2 targets for improvement in current treatment practice for AUCa.


Kordolaimi S.D.,National and Kapodistrian University of Athens | Salvara A.L.N.,National and Kapodistrian University of Athens | Antonakos I.,National and Kapodistrian University of Athens | Tsalafoutas I.A.,Agios Savvas Hospital | And 2 more authors.
Physica Medica | Year: 2013

Purpose: To compare two angiography systems of different image capture technology, one with flat detector (FD) and one with image intensifier (II), in terms of entrance surface air kerma (ESAK) rate, detector dose (DD) rate and image quality (IQ), in interventional cardiology procedures concerning both adult and pediatric patients. Materials and methods: In order to determine ESAK and DD rates, a digital dosimeter and polymethylmethacrylate (PMMA) plates were used. For the evaluation of IQ, two contrast objects (the Leeds TOR 18FG and a 5 mm-thick Aluminum plate) were used and two figures of merit were defined in fluoroscopy and cine acquisition modes. Measurements of ESAK, DD rates and IQ were made for various fields of view, pulse and frame acquisition rates. Results: For the particular setup used in this study was noted that ESAK values in the II system were generally larger than the respective values in the FD system (on average 70% for fluoro mode, 5 times for cine mode). When halving the fluoroscopy pulse rate, reduction in ESAK was not proportional, in fluoroscopy mode. Image quality evaluations indicated that II performs better in terms of low contrast sensitivity (LCS) and signal-to-noise ratio (SNR) than the FD system which performs better regarding high contrast resolution (HCR). However, when considering image quality in relation to ESAK the FD system performs better than the II system (with the exception of low thicknesses and zooms for high pulse rates in the fluoroscopy mode). Conclusions: The FD system, generally, provides a better image quality-dose relation than the II system although II unit provides better LCS and SNR. This means that with the right adjustments to both systems, FD unit is able to provide same image quality with lower dose. However, newer technology does not automatically imply better image quality and further investigation is necessary for deriving safe conclusions for units which utilize different capture technology. © 2012 Associazione Italiana di Fisica Medica.


PubMed | Agios Savvas Hospital, National and Kapodistrian University of Athens and Konstantopouleio General Hospital
Type: Journal Article | Journal: Radiation protection dosimetry | Year: 2016

All orthopaedic fluoroscopic procedures performed using C-arm guidance were monitored for 1 y. The type of procedure, fluoroscopy time (T), kerma-area product (KAP) values and number of radiographs (F) were recorded. The two most often performed techniques were as follows: intramedullary nailing (IMN) of intertrochanteric/peritrochanteric (IP) fractures (101 cases, 49.3 %) and antergrade IMN of femur or tibia shaft (TS) fractures (28 cases, 13.7 %). For the remaining procedures, none accounted for >5 %, categorised as various (76 cases, 37 %). Large variations in T, KAP and F were observed. For IMN of IP fractures, antergrade IMN of femur and TS fractures and for various procedures, respectively, median values were T--2.1, 2.2 and 0.6 min, KAP--6.3, 6.3 and 0.6 Gy cm(-2) and F--21, 2.2 and 6.7. The patient doses during fluoroscopically guided procedures are relatively low compared with other interventional procedures.


Papastergiou V.,General Hospital of Rhodes | Dimitroulopoulos D.,Agios Savvas Hospital | Skorda L.,General Hospital of Rhodes | Lisgos P.,General Hospital of Rhodes | And 3 more authors.
Journal of Medical Virology | Year: 2012

Hepatitis C virus genotype 4 (HCV-4) is spreading beyond Africa and the Middle East but data regarding treatment with pegylated interferon alpha and ribavirin of European populations infected with HCV-4 remains limited. Interestingly, European (vs. Egyptian) origin has been associated with lower sustained virological response rates. Hence the aim of this study was to investigate the treatment outcomes of Greek (vs. Egyptian), treatment-naïve patients infected with HCV-4 (subtype a) and to identify factors influencing response rates. One hundred seventy-seven consecutive patients (mean age: 44.6±10.2, males: 143/177; 80.8%, Egyptians: 76/177; 42.9%) treated over a 7-year period at the Hepatology clinics of three tertiary care hospitals in Greece were retrospectively evaluated. Overall, sustained virological response was achieved in 75/177 (42.4%) of the cohort without a significant difference between the two ethnic groups [Greek: 44/101 (43.6%); Egyptian 31/76 (40.8%), P=0.7598]. In multivariate analysis, it was found that ethnicity was not associated with an impaired response but age ≥45 years [odds ratio (OR): 0.4225, 95% confidence interval (CI): 0.2135-0.8133; P=0.0134], diabetes (OR: 0.2346, 95% CI: 0.0816-0.0674; P=0.0071), advanced liver fibrosis (OR: 0.3964, 95% CI: 0.1933-0.8133; P=0.0116), and treatment suspension (OR: 0.1738, 95% CI: 0.0482-0.6262; P=0.0075) showed an independent negative association with response to antiviral treatment. In contrast to previous European data suggesting Egyptian ethnicity to be a positive predictor for a sustained virological response, there was no influence of Greek versus Egyptian ethnicity on treatment outcomes. Higher age, advanced liver fibrosis, and diabetes have been shown to reduce significantly response rates in patients infected with HCV-4. © 2012 Wiley Periodicals, Inc..


PubMed | Konstantopoulio Hospital, Agios Savvas Hospital and Raymed & Co LTD
Type: Journal Article | Journal: Physica medica : PM : an international journal devoted to the applications of physics to medicine and biology : official journal of the Italian Association of Biomedical Physics (AIFB) | Year: 2015

To investigate skin dose in Computed Tomography (CT) and its dependence on scanning geometry.Measurements of entrance surface air kerma (ESAK) in free air and entrance skin dose (ESD) on an anthropomorphic phantom were performed in a 64-slice CT scanner, using two different instruments: the Dose Profiler (DP) and the QED skin diode (QEDSD). Using DP and QEDSD, the ESAK rate profiles at the isocenter and at different distances from it, were measured using axial scans. Using DP and helical scans the ESAK rate profile in the Z-axis was acquired. The same profile was acquired with the QEDSD also, using many axial scans and manual table translation. ESD measurements were performed with the DP and QEDSD, in axial and helical scan mode.ESAK measurements with DP and QEDSD were in good agreement, for both point dose and profile measurements. The agreement was also good for ESD measurements but not for helical scans, due to variable X-ray beam overlapping and different tube angular positions at each scan start. It was observed that the ESD values at different Y-axis offsets were comparable to the respective ESAK values recorded at the same Y-axis offset distances without the phantom.Both DP and QEDSD were proven suitable for performing point ESD measurements. However, calculating the skin dose distribution in CT examinations is a very challenging task. A practical approach would be for CT scanners to provide a conservative estimate of the peak skin dose using the isocenter ESAK value.


Tsapaki V.,Konstantopoulio Hospital | Tsalafoutas I.A.,Agios Savvas Hospital | Triantopoulou C.,Konstantopoulio Hospital | Kolliakou E.,Konstantopoulio Hospital | And 2 more authors.
Physica Medica | Year: 2014

Objective: To calculate the cumulative effective and skin doses in patients that underwent repeated CT guided radiofrequency ablations (RFA). Materials and methods: From all patients that had undergone RFA during a five years period those which had three or more RFAs were selected. Using the CT images DICOM data, the dose length product (DLP), effective dose (E), skin dose profiles as well as the peak skin dose (PSD) were calculated, using appropriate methods and software developed for this purpose. For each patient, cumulative DLP and E were also calculated from the sum of the respective figures of each individual procedure. To calculate PSD, the skin dose profiles of each procedure were overlaid on the same Z-axis scale using anatomical landmarks for reference and the skin doses to each point were summed up. Results: Five patients were studied; four had undergone 3 RFAs and one 10 RFAs. Cumulative DLP, E and PSD ranges were 5.6-22.3Gycm, 0.08-0.36Sv and 0.8-3.4Gy, respectively. Median E and PSD values per RFA were 35mSv and 0.4Gy, respectively. For comparison purposes it must be noted that in this CT department a routine abdomen-pelvis scan results to an E of about 10mSv. Conclusions: Patients that undergo repeated RFAs are exposed to considerably high radiation exposure levels. When these patients are in the final stage of malignant diseases, stochastic effects may not be of major concern. However, optimization of the exposure factors and monitoring of these patients to avoid skin injuries are required. © 2013 Associazione Italiana di Fisica Medica.


Tsalafoutas I.A.,Agios Savvas Hospital | Georgolopoulou P.,Agios Savvas Hospital | Abatzoglou I.,University General Hospital of Alexandroupolis
Physica Medica | Year: 2012

Purpose: To experimentally investigate the effect of the scan field of view (SFOV) selection and table height settings on the Computed Tomography Dose Index (CTDI) and the implications concerning patient effective and skin dose. Methods: Air-kerma length product (AKLP) measurements were carried out in a helical CT scanner using a pencil type dosimeter positioned in air and inside the holes of a head and a body phantom, using all available SFOV selections and different table height settings. Furthermore, using radiotherapy verification films placed on the CT table surface, the entrance surface air kerma (ESAK) profiles were derived with different SFOV and table height selections, both with and without a phantom on top of the films. Results: The AKLP is strongly dependent on the SFOV selection and the table height settings. Different SFOV selections correspond to the selection of different bowtie filters that shape the X-ray beam intensity, resulting in different ESAK values at the isocenter and at the other points within the scanning plane. With the off-center positioning the calculated CTDI values within the center and the periphery of the phantom change also, as a result of the different intensity and width of the X-ray beam to which are exposed to. Conclusions: The existing protocols for calculating effective dose are limited to only two patient anatomy-SFOV combinations and cannot account for off-center positioning. Therefore, more work will be required to estimate the effective and skin dose for non-standard SFOV-patient anatomy combinations and off-center patient positioning. © 2011 Associazione Italiana di Fisica Medica.


Stamatopoulou S.,Agios Savvas Hospital
Memo - Magazine of European Medical Oncology | Year: 2013

Hodgkin lymphoma (HL) and systemic anaplastic large-cell lymphoma (sALCL) are lymphoproliferative types of cancer. The chemotherapy regimens of HL such as ABVD (doxorubicin, bleomycin, vinblastine, decarbazine) and BEACOPP (bleomycin, etoposide, doxorubicin, cyclophospamide, vincristine, procarbazine, prednisone) have made the most curable malignancies. Unfortunately, 15-30 % of these patients will relapse again and treatment options become limited, so we need to develop new therapeutic approaches. ALCL has unique molecular and immunohistochemical features that make it an ideal model for developing targeted therapies. Antibody-drug conjugates (ADCs), consist of an antibody, a cytotoxic agent, a stable linker and allow delivery of high doses of cytotoxic drugs to cancer cells while sparing normal tissues exposure to high systemic concentration of the cytotoxic agent. Brentuximab vedotin is an anti-CD30 monoclonal antibody conjugate with a potent microtubule inhibitor monomethyl auristatin E. In August 2011, the United States Food and Drug Administration (FDA) approved brentuximab vedotin to treat HL after failure of autologous stem cell transplantation or at least two combination chemotheraphy regimens and for sALCL after failure of at least one prior multidrug chemotherapy regimen. With this approval, brentuximab vedotin is a promising ADC directed against the CD30 antigen. © 2013 Springer-Verlag Wien.


Tsalafoutas I.A.,Agios Savvas Hospital | Metallidis S.I.,Computer Services
British Journal of Radiology | Year: 2011

Objective: The dosimetric calculations in CT examinations are currently based on two quantities: the volume weighted CT dose index (CTDIvol) and the dose - length product (DLP). The first quantity is dependent on the exposure factors, scan field of view, collimation and pitch factor selections, whereas the second is additionally dependent on the scan length. Methods: In this study a method for the calculation of these quantities from digital imaging and communication in medicine (DICOM) CT images is presented that allows an objective audit of patient doses. This method was based on software that has been developed to enable the automatic extraction of the DICOM header information of each image (relating to the parameters that affect the aforementioned quantities) into a spreadsheet with embedded functions for calculating the contribution of each image to the CTDIvol and DLP values. The applicability and accuracy of this methodwas investigated using data from actual examinations carried out in three different multislice CT scanners. These examinations have been performed with the automatic exposure control systems activated, and therefore the tube current and tube loading values varied during the scans. Results: The calculated DLP values were in good agreement (±5%) with the displayed values. The calculated average CDTI vol values were in similar agreement with the displayed CTDI vol values but only for two of the three scanners. In the other scanner the displayed CTDIvol values were found to be overestimated by about 25%. As an additional application of this method the differences among the tube modulation techniques used by the three CT scanners were investigated. Conclusion: This method is a useful tool for radiation dose surveys. © 2011 The British Institute of Radiology.


Tsalafoutas I.A.,Agios Savvas Hospital
Physica Medica | Year: 2011

Helical scanning requires the irradiation of larger lengths than those planned. This is referred to as overscan and results to an increase of patient dose. Its impact on patient dose was investigated for three first generation multislice CT scanners; a six-, a quad- and a dual-slice. The amount of overscan was determined using the scanners' dose-length product (DLP) indications and films positioned on the CT table. With the preset protocol for the chest examination selected in all CT scanners, the overscan length calculated from the DLP indications was 6.3, 3.5 and 2 cm respectively, whereas the corresponding figures derived from the films were 6.6, 4.8 and 2.5 to 3.2. cm. For a 30 cm scan length, the respective contributions of overscan to the DLP values were 17, 10 and 6%, whereas for a scan length of 20 cm the respective values increased to 24, 15 and 9%. For the smallest scan lengths allowed in helical mode, the respective contributions reached 53, 88 and 67% because for the six-slice scanner the smallest scan length was limited to twice the collimation, whereas in the quad and dual scanners no limitation existed. For small scan lengths the presence of overscan cancels out any dose reduction offered by helical scanning with pitch factor values larger than one and therefore the axial mode should be preferred, when this is not prohibited by the diagnostic task in question. © 2010 Associazione Italiana di Fisica Medica.

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