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EN
Exact pretherapeutic staging is considered to be essential for decision-making in the therapeutic algorithm of gastric cancer.The aim of the study was to characterize the role and value of EUS in the diagnostic and therapeutic management of gastric cancer in daily surgical practice.Material and methods. Thousand one hundred thirty nine patients with primary gastric cancer from 80 hospitals of each profile of care were enrolled in this systematic clinical prospective multicenter observational study over a time period of 12 months. The characteristics of the diagnostic management, in particular, of EUS were documented. The preoperative EUS findings were compared with the T stage (T1 to T4) and the N category (N+ or N-) revealed by the histopathologic investigation of the surgical specimen. By the mean of X2 test, the impact of EUS on the therapeutic decision-making was determined.Results. Pretherapeutic EUS was only performed in 27.4% (n=312) of all patients. Overall, the diagnostic accuracy for the T stage was 42.6% in average. The subgroup analysis showed the following results: T1, 31.5%; T2, 42.6%; T3, 65.2%; T4, 17.6%. The correct predictive value of the N category was 71.3% reaching a sensitivity of 69.7% and a specificity of 73.3%. Overstaging was observed in 45.8%, understaging in only 10.8%. Additional diagnostic information by EUS was only provided in 4.7% of subjects.Conclusions. The present study indicates the variability, limited reliability and only moderate acceptance of EUS in diagnosing gastric cancer in daily practice. In particular, the prediction of the T stage does not reach the data reported in the literature, which were mostly achieved in specific EUS studies.
EN
A crucial technological task that must be solved in the production of sausage products is to stabilize the product’s red colour. In this paper, we propose a scheme to determine the most significant parameters of the quality of dry-cured sausages by their colour characteristics. For this purpose, colour digital images were obtained, which were further processed using two classical colour representation systems: RGB and xyY. We monitored changes in pH and the ratio of water to dry matter in meat products. These crucial sausage properties were changed by introducing chitin-containing supplements into their recipes, which allowed us to solve two tasks simultaneously. The first comprises, as already mentioned, changing the properties of sausages to obtain correlations with colour characteristics. The second is to enrich meat products with chitin complex for preventive purposes to improve people’s nutrition. The construction of correlation dependencies using each coordinate separately in two colour systems showed that each system (RGB and xyY) has one colour channel with a maximum correlation coefficient. This is due to the colour features of sausages, which can be represented to the greatest extent with the help of only one colour coordinate in the considered colour representation systems (RGB and xyY). Using these colour coordinates will allow one to achieve maximum measurement accuracy. Thus, two tasks are being solved: the enrichment of food with dietary supplement and the development of a method to control their content.
EN
The aim of the paper was to present the possibility of applying the novel method (RP-HPLC ion pair method) for the simultaneous dissolution determination of combined tablet dosage form containing acetylsalicylic acid and glycine in pharmaceutical industry. The samples were gradient eluted using a Pursuit XS Ultra C18 column (150x3.0 mm, with a particle size of 2.8µm) with variable composition of mobile phase A (1-heptanesulfonic acid sodium salt aqueous solution (2.8 g/L), pH 2.2 ± 0.05 adjusted with orthophosphoric acid) and phase B (methanol). The detection was carried out at 210 nm with a consist flow rate of 0.4 mL min−1. The method was validated by determining precision (repeatability and intermediate precision), accuracy, specificity, linearity, range, system suitability, robustness and stability in accordance with ICH guidelines. The method was accurate, precise and linear within the range of 0.03 – 0.18 mg mL−1 for acetylsalicylic acid and 0.016 – 0.096 mg mL−1 for glycine. The method is simple, convenient and suitable for analyzing acetylsalicylic acid and glycine in pharmaceutical formulations. The method could also be used for routine assay determination after small modification of sample preparation.
EN
High requirements on the API quality mean that the quality control of the starting material is crucial to the manufacturing process of drug substances. Three sensitive methods for the purity determination of the following starting materials: ethylene glycol (method I), 3-acetylpyridine (method II) and 4-chloromethyl-5-methyl-1,3-dioxol-2-one (method III) used in the synthesis of selected drug substances were developed using GC-FID techniques. All the methods were validated according to the International Conference on Harmonization guidelines. The correlation coefficient values were found about 0.99. The obtained RSD values from the replicate injections in the range of 20 - 120% of the nominal concentration ensured the precision.
EN
Quality control (QC) in radiology is meant to ensure that accurate diagnoses are obtained with radiation doses kept as low as reasonably achievable. It is also a fundamental requirement by the Regulatory Authorities in issuing operational license to operators of radiology facilities. In Nigeria, QC issues in Radiation Medicine have recently been introduced and are being enforced by the Nigerian Nuclear Regulatory Authority (NNRA). The level of QC practice in the radiology facilities in Cross River State, Nigeria was evaluated to obtain baseline information that could be relied on in the future to determine the level of improvement. It was observed that radiology practitioners appreciate QC and its importance in their practice, the present low level of its implementation notwithstanding.
EN
The aim of the study was to analyze epidemiologic parameters, treatment-related data and prognostic factors in the management of gastric cancer patients of a university surgical center under conditions of routine clinical care before the onset of the era of multimodal therapies. By analyzing our data in relation with multi-center quality assurance trials [German Gastric Cancer Study - GGCS (1992) and East German Gastric Cancer Study - EGGCS (2004)] we aimed at providing an instrument of internal quality control at our institution as well as a base for comparison with future analyses taking into account the implementation of evolving (multimodal) therapies and their influence on treatment results.Material and methods. Retrospective analysis of prospectively gathered data of gastric cancer patients treated at a single institution during a defined 10-year time period with multivariate analysis of risk factors for early postoperative outcome.Results. From 04/01/1993 through 03/31/2003, a total of 328 gastric cancer patients were treated. In comparison with the EGGCS cohort there was a larger proportion of patients with locally advanced and proximally located tumors. 272 patients (82.9%) underwent surgery with curative intent; in 88.4% of these an R0 resection was achieved (EGGCS/GGCS: 82.5%/71.5%). 68.2% of patients underwent preoperative endoluminal ultrasound (EUS) (EGGCS: 27.4%); the proportion of patients undergoing EUS increased over the study period. Diagnostic accuracy of EUS for T stage was 50.6% (EGGCS: 42.6%). 77.2% of operated patients with curative intent underwent gastrectomy (EGGCS/GGCS: 79.8%/71.1%). Anastomotic leaks at the esophagojejunostomy occurred slightly more frequently (8.8%) than in the EGGCS (5.9%) and GGCS (7.2%); however, postoperative morbidity (36.1%) and early postoperative mortality (5.3%) were not increased compared to the multi-center quality assurance study results (EGGCS morbidity, 45%); EGGCS/GGCS mortality, 8%/8.9%). D2 lymphadenectomy was performed in 72.6% of cases (EGGCS: 70.9%). Multivariate analysis revealed splenectomy as an independent risk factor for postoperative morbidity and ASA status 3 or 4 as an independent risk factor for early postoperative mortality. The rate of splenectomies performed during gastric cancer surgery decreased substantially during the study period.Conclusions. Preoperative diagnostics were able to accurately predict resectability in almost 90% of patients which is substantially more than the corresponding results of both the EGGCS and the GGCS. In the future, more wide-spread use of EUS will play an increasing role as stage-dependent differentiation of therapeutic concepts gains acceptance. However, diagnostic accuracy of EUS needs to be improved. Our early postoperative outcome data demonstrate that the quality standard of gastric cancer care established by the EGGCS is being fulfilled at our institution in spite of distinct characteristics placing our patients at higher surgical risk. Besides being a valuable instrument of internal quality control, our study provides a good base for comparison with ongoing analyses on future developments in gastric cancer therapy.
EN
The Nuclear and Energy Research Institute has produced, since 1998, iridium-192 wires used in low dose rate brachytherapy. In the paper the authors studied the influence of wire profile on the homogeneity distribution of radioactivity of iridium-192 along the wire. The authors propose the improvements in the quality control procedure that will provide more accurate measurement data and suggest changes in control devices.
EN
Introduction: Accurate reproducibility of the radiation field in all stages of radiotherapy is the basic condition for curing cancer permanently while preserving vital surrounding tissues and organs. The progress in information technology has made it possible to replace time-consuming and less accurate portal imaging that uses radiograms with electronic systems for recording and processing images of the radiation beam. Such devices detect possible geometric errors more effectively and enable their verification even during a single radiation fraction. The fact that the precision and individualization of contemporary radiotherapy is aimed at as well as new technical possibilities motivated the authors to search for individual patient-related factors that influence the reproducibility of radiation fields in individual radiotherapy sessions. Aim: The aim of the paper was to assess the influence of selected individual clinical factors on the reproducibility of the radiation field in patients treated due to gynecologic cancers. Material: The material comprised 88 patients with cervical and endometrial cancers in FIGO stages I, II and III, treated in the Department of Teleradiotherapy of Maria Skłodowska-Curie Memorial Cancer Center and Institute of Oncology in Warsaw, Poland. The radiotherapies conducted were radical, primary and adjuvant following previous surgical treatment. Method: Patients received irradiation according to the treatment plans with 6 and 15 MeV X-ray photons with a total dose of 45–60 Gy, 1.5–2.5 Gy in 12–39 (mean 25) fractions. In order to compare patient set-up accuracy with the reference positioning stored in the Vision system, verification images were made during subsequent radiation fractions with the use of electronic portal imaging system from the PA 0° and lateral 90° directions of radiation beams. Differences in relation to the reference images in three directions were compared and entered into tables. The reaction threshold was assumed when the differences between the simulator images and portal images in any of the examined directions were >7 mm. Then, following an error analysis, set-up was verified and corrected simultaneously (online). The size of displacement with respect to the reference image and the mean displacement value were specified in every patient for each of the three directions. For the purposes of the statistical analysis, a displacement vector was determined that expressed total displacement of a patient during radiotherapy with respect to the reference images. A description of the studied group of patients based on clinical features was presented in the table. It includes the performance status, body mass index, diagnosis, stage of the disease, data concerning combination treatment with radiotherapy, including previous surgical treatment and chemotherapy, as well as aggravation of early radiation reactions of the urinary bladder and intestine. The authors analyzed the influence of the selected individual clinical factors on the reproducibility of the radiation field, which was expressed with the displacement vector. The chi-square test of dependence was used to assess correlations between the value of the displacement vector and the aforementioned clinical and pathological features. The level of statistical significance of p = 0.05 referred to all comparisons. Results: The analysis involved 382 portal images that verified patient set-up, based on which a total of 1528 measurements were performed according to the above mentioned principles. For each analyzed patient, the value of the displacement vector was calculated. The mean value for all patients was 0.44 (0.02–1.82, standard deviation 0.27). The chi-square test of dependence revealed a statistically significant influence of obesity expressed as the body mass index (BMI) (p = 0.003), presence of early intestinal radiation reactions (p = 0.034) and previous surgical treatment (p = 0.046) on worse reproducibility of radiation fields expressed as the value of the displacement vector. Conclusions: Obesity expressed as the body mass index (BMI) ≥30.0, presence of acute intestinal radiation reactions during radiotherapy and surgical treatment conducted at the first stage of treatment deteriorate the reproducibility of the radiation field in a statistically significant way in patients treated due to gynecologic cancers.
PL
Wstęp: Dokładna odtwarzalność obszaru napromieniania we wszystkich etapach radioterapii jest podstawowym warunkiem trwałego wyleczenia przy jednoczesnym oszczędzeniu ważnych dla zdrowia otaczających tkanek i narządów. Postęp techniki informatycznej pozwolił zastąpić czasochłonną i mniej dokładną metodę obrazowania portalowego z użyciem radiogramów systemami elektronicznej rejestracji i przetwarzania obrazu wiązki promieniowania. Urządzenia te skuteczniej wykrywają zaistniałe błędy geometryczne i pozwalają weryfikować je nawet w czasie tej samej frakcji napromieniania. Dążenie do zwiększenia precyzji i indywidualizacji nowoczesnej radioterapii oraz nowe możliwości techniczne skłoniły autorów do poszukiwania indywidualnych czynników związanych z pacjentem, które wpływają na odtwarzalność pól napromieniania w poszczególnych seansach radioterapii. Cel pracy: Celem pracy jest ocena wpływu wybranych indywidualnych czynników klinicznych na odtwarzalność obszaru napromieniania u chorych leczonych z powodu nowotworów ginekologicznych. Materiał: Analizowany materiał stanowiło 88 kolejnych chorych na raka szyjki i trzonu macicy w I, II i III stopniu zawansowania wg FIGO, leczonych w Zakładzie Teleradioterapii Centrum Onkologii – Instytutu im. Marii Skłodowskiej-Curie w Warszawie. Stosowano napromienianie z założeniem radykalnym, pierwotne i uzupełniające po uprzednim leczeniu chirurgicznym. Metoda: Chore były napromieniane według planów leczenia fotonami X o energii 6 i 15 MeV, dawką całkowitą 45–60 Gy, frakcjonowaną 1,5–2,5 Gy w 12–39 (średnia 25) frakcjach. W czasie kolejnych frakcji napromieniania w celu porównania poprawności ułożenia chorej w stosunku do ułożenia referencyjnego zapisanego w systemie Vision wykonano obrazy weryfikacyjne w elektronicznym systemie obrazowania portalowego z kierunków wejścia wiązek PA 0° i bok 90°. Różnice w stosunku do obrazów referencyjnych w trzech kierunkach zostały porównane i zapisane w tabelach. Przyjęto próg reagowania, gdy różnice między obrazem uzyskanym z symulatora i z obrazu portalowego w dowolnym z badanych kierunków wynosiły >7 mm, wówczas podejmowano po analizie błędów weryfikację ułożenia z korektą jednoczasową (online). U wszystkich chorych określono dla każdego z trzech kierunków wielkość przesunięcia względem obrazu referencyjnego i średnią wartość przesunięcia. Na potrzeby analizy statystycznej wyznaczono wektor przesunięcia wskazujący całkowite przesunięcie chorego w trakcie napromieniania względem obrazów referencyjnych. Charakterystykę badanej grupy chorych pod względem cech klinicznych zestawiono w tabeli, uwzględniając stopień sprawności, indeks masy ciała, rozpoznanie, stopień zaawansowania nowotworu, stosowane leczenie skojarzone z radioterapią, w tym przebyty zabieg chirurgiczny i chemioterapię, nasilenie wczesnych odczynów popromiennych ze strony pęcherza moczowego i jelit. Analizowano wpływ wybranych czynników klinicznych na odtwarzalność obszaru napromieniania wyrażoną wartością wektora przesunięcia. Testem zależności chi-kwadrat oceniono korelację pomiędzy wartością wektora przesunięcia a wymienionymi cechami klinicznymi i patologicznymi. We wszystkich porównaniach przyjęto poziom istotności statystycznej p = 0,05. Wyniki: Poddano analizie 382 obrazy portalowe weryfikujące ułożenie pacjentek, na których dokonano łącznie 1528 pomiarów według powyższych zasad. Obliczono dla każdej analizowanej chorej wartość wektora przesunięcia. Średnia wartość dla wszystkich chorych wynosiła 0,44 (0,02–1,82, odchylenie standardowe 0,27). Testem zależności chi-kwadrat wykazano znamienny statystycznie wpływ otyłości wyrażonej wskaźnikiem masy ciała (BMI) (p = 0,003), występowania wczesnego odczynu popromiennego z jelit (p = 0,034) oraz przebytego leczenia chirurgicznego (p = 0,046) na gorszą odtwarzalność pól napromieniania wyrażoną wartością wektora przesunięcia. Wnioski: Otyłość wyrażona wskaźnikiem masy ciała BMI ≥30,0, wystąpienie ostrego odczynu popromiennego z jelit w trakcie radioterapii oraz przebyty w pierwszym etapie leczenia zabieg chirurgiczny istotnie statystycznie pogarszają odtwarzalność obszaru napromieniania u chorych leczonych z powodu nowotworów ginekologicznych.
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