Lege Artis Medicinae

[When to stop a clinical trial of a medicine?]

STUART Pocock

MARCH 31, 1993

Lege Artis Medicinae - 1993;3(03)

[Most randomised clinical trials require periodic evaluation of the data collected. On the one hand, monitoring the data increases the effectiveness of the trial and, on the other hand, ethical considerations are based on the partial results, which may lead to the termination or modification of the trial. This article discusses the ethical question of when to stop a clinical trial of a drug, and presents the statistical rules for stopping trials related to these ethical decisions. Other topics include the question of the organisation of data assessment committees, premature publication and the problem of overestimation in discontinued trials. A number of examples on this topic help to ensure that the issues discussed can be applied in daily practice.]

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[In 1987 breast cancer occupied the 3rd place among female cancers in the world. In Hungary, 13.577 women died due to cancer in 1990, 15,4% from breast cancer. The author uses international, and Hungarian data (at the country and county level) and also the data from his own research results. Incidence of breast cancer has risen continuously and shows a wide range in different parts of the world from 14,1 %000/year to 121,2%8000/year. The 5 year crude survival rate is between 40–65% and is slowly improving. In addition to the well-known risk-factors, the author emphasizes the role of mastopathy because in his patient group of 843 cases 2,3%, but in the mastopathy group 4,1% developed cancer. Therefore, this alteration should be considered as a high risk factor. Among close female relatives of breast cancer patients breast and other cancer has occurred much more frequently, than in that of a control group. Prostate cancer occurs significantly more frequently among 1 st degree male relatives. Therefore it is necessary to study the risk factors with epidemiologic methods and to broaden screening, detection and therapy in order to reduce the incidence and mortality of breast cancer. ]

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[There is no data in the medical literature concerning the late results of breast physical exam by paramedical personnel as a screening test. In a population screening for breast cancer in Debrecen, nearly 70 thousand women were observed from 1981 to 1985 and 298 new breast cancer patients were detected. 198 patients were from the screened population and 100 patients from the non screened population. All of the breast cancer patients were followed up, and the analysis was completed on 31st December 1991 with the help of statistical methods. The author analysed the overall survival, cumulative death rate and relative risk of dying according to age group. The difference of overall survival was 29% for the screened group. This result is nearly the same as that produced by mammographic screening.]

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[The author interpretes and evaluates the diagnostic methods of breast cancer. Detailed description is given on physical examination, mammography, ultrasound examination, cytology, histology and miscellaneous methods, expressing their advantages and drawbacks. On clinical experience nowadays the combinative application of these by the same expert seems to be the most effective method, possibly in large breast clinic centres.]

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Although vertigo is one of the most common complaints, intracranial malignant tumors rarely cause sudden asymmetry between the tone of the vestibular peripheries masquerading as a peripheral-like disorder. Here we report a case of simultaneous temporal bone infiltrating macro-metastasis and disseminated multi-organ micro-metastases presenting as acute unilateral vestibular syndrome, due to the reawakening of a primary gastric signet ring cell carcinoma. Purpose – Our objective was to identify those pathophysiological steps that may explain the complex process of tumor reawakening, dissemination. The possible causes of vestibular asymmetry were also traced. A 56-year-old male patient’s interdisciplinary medical data had been retrospectively analyzed. Original clinical and pathological results have been collected and thoroughly reevaluated, then new histological staining and immunohistochemistry methods have been added to the diagnostic pool. During the autopsy the cerebrum and cerebellum was edematous. The apex of the left petrous bone was infiltrated and destructed by a tumor mass of 2x2 cm in size. Histological reexamination of the original gastric resection specimen slides revealed focal submucosal tumorous infiltration with a vascular invasion. By immunohistochemistry mainly single infiltrating tumor cells were observed with Cytokeratin 7 and Vimentin positivity and partial loss of E-cadherin staining. The subsequent histological examination of necropsy tissue specimens confirmed the disseminated, multi-organ microscopic tumorous invasion. Discussion – It has been recently reported that the expression of Vimentin and the loss of E-cadherin is significantly associated with advanced stage, lymph node metastasis, vascular and neural invasion and undifferentiated type with p<0.05 significance. As our patient was middle aged and had no immune-deficiency, the promoting factor of the reawakening of the primary GC malignant disease after a 9-year-long period of dormancy remained undiscovered. The organ-specific tropism explained by the “seed and soil” theory was unexpected, due to rare occurrence of gastric cancer to metastasize in the meninges given that only a minority of these cells would be capable of crossing the blood brain barrier. Patients with past malignancies and new onset of neurological symptoms should alert the physician to central nervous system involvement, and the appropriate, targeted diagnostic and therapeutic work-up should be established immediately. Targeted staining with specific antibodies is recommended. Recent studies on cell lines indicate that metformin strongly inhibits epithelial-mesenchymal transition of gastric cancer cells. Therefore, further studies need to be performed on cases positive for epithelial-mesenchymal transition.

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[In this paper we present the Comprehensive Aphasia Test-Hungarian (CAT-H; Zakariás and Lukács, in preparation), an assessment tool newly adapted to Hungarian, currently under standardisation. The test is suitable for the assessment of an acquired language disorder, post-stroke aphasia. The aims of this paper are to present 1) the main characteristics of the test, its areas of application, and the process of the Hungarian adaptation and standardisation, 2) the first results from a sample of Hungarian people with aphasia and healthy controls. Ninety-nine people with aphasia, mostly with unilateral, left hemisphere stroke, and 19 neurologically intact control participants were administered the CAT-H. In addition, we developed a questionnaire assessing demographic and clinical information. The CAT-H consists of two parts, a Cognitive Screening Test and a Language Test. People with aphasia performed significantly worse than the control group in all language and almost all cognitive subtests of the CAT-H. Consistent with our expectations, the control group performed close to ceiling in all subtests, whereas people with aphasia exhibited great individual variability both in the language and the cognitive subtests. In addition, we found that age, time post-onset, and type of stroke were associated with cognitive and linguistic abilities measured by the CAT-H. Our results and our experiences clearly show that the CAT-H provides a comprehensive profile of a person’s impaired and intact language abilities and can be used to monitor language recovery as well as to screen for basic cognitive deficits in aphasia. We hope that the CAT-H will be a unique resource for rehabilitation professionals and aphasia researchers in aphasia assessment and diagnostics in Hungary. ]

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[A short chronicle of three decades ]

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[Hungarian professional periodicals started quite late in European context. Their publish­ing, editing and editorial philosophy were equally influenced by specific historical and political situations. Certain breaking points of history resulted in termina­tion of professional journals (War of In­de­pendence 1848-1849, First and Se­cond World Wars), however there were pe­riods, which instigated the progress of sciences and founding of new scientific journals. Both trends were apparent in years after the fall of former Hungarian regime in 1990. The structure of book and journal publishing has changed substantially, some publishers fell “victim” others started successfully as well. The latters include the then-established publishing house Literatura Medica and its own scientific journal, Lege Artis Me­di­cinae (according to its subtitle: New Hun­garian Medical Herald) issued first in 1990. Its appearance enhanced significantly the medical press market. Its scientific publications compete with articles of the well-established domestic medical journals however its philosophy set brand-new trends on the market. Concerning the medical community, it takes on its problems and provides a forum for them. These problems are emerging questions in health care, economy and prevention, in close interrelation with system of public health institutions, infrastructure and situation of those providing individual health services. In all of them, Lege Artis Medicinae follows consequently the ideas of traditional social medicine.]

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