Biomedical subjects

T Dyba

Publications and source records attributed to T Dyba.

15 recordsLinked to original sources

PubMed2000

Comparison of different approaches to incidence prediction based on simple interpolation techniques.

The paper compares three different methods for performing disease incidence prediction based on simple interpolation techniques. The first method assumes that the age-period specific numbers of observed cases follow a Poisson distribution and the other two methods assume a normal distribution for the incidence rates. The main emphasis of the paper is on assessing the reliability of the three methods. For this purpose, ex post predictions produced by each method are checked for different cancer sites using data from the Cancer Control Region of Turku in Finland. In addition, the behaviour of the estimators of predicted expected values and prediction intervals, crucial for investigation of the reliability of prediction, are assessed using a simulation study. The prediction method making use of the Poisson assumption appeared to be the most reliable of the three approaches. The simulation study found that the estimator of the length of the prediction interval produced by this method has the smallest coverage error and is the most precise.

Adult↗

PubMed2000

Correction

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Journal Article↗

PubMed1997

A simple non-linear model in incidence prediction.

A simple model is proposed for incidence prediction. The model is non-linear in parameters but linear in time, following models in environmental cancer epidemiology. Assuming a Poisson distribution for the age and period specific numbers of incident cases approximate confidence and prediction intervals are calculated. The major advantage of this model over current models is that age-specific predictions can be made with greater accuracy. The model also preserves in the period of prediction the age pattern of incidence rates existing in the data. It may be fitted with any package which includes an iteratively reweighted least squares algorithm, for example GLIM. Cancer incidence predictions for the Stockholm-Gotland Oncological Region in Sweden are presented as an example.

Adult↗

PubMed1997

Cancer survival in Estonian migrants to Sweden.

OBJECTIVE: To quantify the eventual extra loss of life incurred to cancer patients in Estonia compared with those in Sweden that was possibly attributable to differences in society. DESIGN: Population based survival of cancer patients in Estonia was compared with that of Estonian immigrants to Sweden and that of all cancer patients in Sweden. The cancer sites studied were female breast and ovary, male lung and prostate, and male and female stomach and colon. SETTING: Data on incident cases of cancer were obtained from the population based Swedish and Estonian cancer registries. PARTICIPANTS: Data from Estonian patients in Sweden, Estonian patients in Estonia, and patients from the total Swedish population were included in the study. MAIN RESULTS: Differences in survival among the three populations, controlling for follow-up time and age at diagnosis, were observed in breast, colon, lung, ovarian, and prostate cancers. The survival rates of Estonians living in Sweden and the total population of Sweden were better than that of the Estonians living in Estonia. For cancers of the breast and prostate, the excess mortality in the older age group (75 and above) was much greater in Estonia than in the other populations. CONCLUSIONS: Most differences in cancer survival between Estonian and Swedish populations studied could be attributed to a longer delay in diagnosis, and also to inferior treatment (including access to treatment) in Estonia compared with Sweden. Estonia's lag in socioeconomic development, particularly in its public health organisation and funding, is probably the main source of the differences observed.

Adolescent↗

PubMed1997

Evaluation of certain risk factors for lung cancer in Cracow (Poland)--a case-control study.

The relationship of lung cancer risk to cigarette smoking, occupational exposure, air pollution at permanent residence and usual frequency of consumption of fruits and vegetables was analysed in a case control study in Cracow, Poland. The cases were 176 male lung cancer patients diagnosed in 1992-1994 with histological confirmation of the diagnosis, obtained from the population-based Cracow Cancer Registry, and 341 controls randomly selected from the general population. Classification of exposure to outside air pollution was based on measured level of total suspended particular matter and sulphur dioxide by particular districts of town (from 1973 to 1980). Except calculation of odds ratios for male lung cancer associated with exposures among all study subjects, the association between lung cancer risk and frequency of consumption of fruit and vegetables was examined among drinkers of vodka above average. Risk of lung cancer was increased significantly with increasing number of pack-years of smoking (OR = 18.7 for more than 40 pack-years). The significant inverse association of frequent usual consumption of boiled vegetables was present both among all subjects and among vodka drinkers (OR = 4.6 and 12.5, respectively, for a rare consumption). The risk of male lung cancer was negatively associated with the level of air pollution but positively with the percentage of occupationally exposed. Our study provides no evidence of a significant harmful effect of air pollution and found a strong inverse association between frequent fruit and vegetables consumption and lung cancer risk.

Adult↗

PubMed1996

Dietary factors and risk of prostate cancer in Poland. Results of case-control study.

The relationship between cigarette smoking, vodka drinking and consumption of 44 food items typical of the Polish diet were analyzed in a case-control study performed in Cracow, Poland, among 76 cases of prostate cancer and 152 controls. Cigarette smoking and drinking of vodka were not significantly influencing the prostate cancer. The men who ate smoked or fried fish or liver at least once per week had almost half of the risk of prostate cancer of the men who ate those food rarely.

Aged↗

PubMed1995

Relationship of histology, DNA-values and proliferative activity in unselected breast cancer patients (a preliminary study).

Based upon a group of 108 consecutive mammary carcinomas a comparative analysis of morphological parameters, DNA-ploidy and indicators of proliferation activity was made. A correlation between Bloom-Richardson scale, mitotic index, PCNA-labeling index and DNA-index was shown. The ploidy of mammary carcinomas was significantly related to the values of proliferative fraction, as well as to PCNA-labeling index. Among patients with axillary metastases the tumor size and the value of PCNA-labeling index were significantly higher than those in patients with negative lymph nodes.

Adult↗

PubMed1995

[Ovarian cancer and selected life style habits].

Analysis of population based case-control study performed in Cracow Poland in 1988-1990 on 81 cases of histologically proven epithelial ovarian cancer and 162 age matched controls have shown that frequent consumption of legumes was associated with significantly decreased risk. Smoking and drinking of vodka were not significant related to ovary cancer risk.

Adult↗

PubMed1994

Reproductive history and prognosis in patients with operable breast cancer.

BACKGROUND: Late menarche, early menopause, high parity, and early first birth decrease the risk of development of breast cancer. The influence of these factors on the survival of breast cancer patients has not been explained. METHODS: A group of 1885 patients with operable breast cancer was studied retrospectively. A univariate analysis was used to calculate 10-year overall survival (OS) and disease free survival (DFS) in relation to age, menopausal status, age at menarche and menopause, and number of pregnancies and deliveries. A multivariate analysis (Cox model) was performed in which classic prognostic factors (tumor size and grade, lymph node involvement) were included in addition to reproductive factors. RESULTS: Univariate analysis demonstrated better prognosis in patients who had never been pregnant compared with those who had (OS, 62% vs. 54%, respectively; P = 0.01; DFS, 53% vs. 44%, respectively; P = 0.005) and in nulliparous compared with parous patients (OS, 62% vs. 53%, respectively; P = 0.006; DFS, 52% vs. 44%, respectively; P = 0.004). Survival rates decreased with the number of pregnancies and deliveries. Patients with late menarche had worse survival then those whose first menstruation occurred before the age of 16 years (DFS, 47% vs. 41%, respectively; P = 0.04). By multivariate analysis, parity remained an independent prognostic indicator in addition to classic highly significant prognostic factors (nodal involvement, tumor grade and size). CONCLUSIONS: Results suggest that reproductive factors known to decrease the risk of breast cancer development have an adverse effect on prognosis.

Abortion, Spontaneous↗

PubMed1994

Precision of incidence predictions based on Poisson distributed observations.

Disease incidence predictions are useful for a number of administrative and scientific purposes. The simplest ones are made using trend extrapolation, on either an arithmetic or a logarithmic scale. This paper shows how approximate confidence prediction intervals can be calculated for such predictions, both for the total number of cases and for the age-adjusted incidence rates, by assuming Poisson distribution of the age and period specific numbers of incident cases. Generalizations for prediction models, for example, using power families and extra-Poisson variation, are also presented. Cancer incidence predictions for the Stockholm-Gotland Oncological Region in Sweden are used as an example.

Adult↗

PubMed1994

Classical prognostic factors for survival and loco-regional control in breast cancer patients treated with radical mastectomy alone.

A retrospective analysis of clinical and pathological prognostic factors was performed in 1,068 breast cancer patients treated with radical mastectomy alone in 1952-1980. Three endpoints were considered: 10-year survival, 10-year disease-free survival and 10-year loco-regional relapse-free survival. Both univariate and multivariate analyses confirmed the prognostic significance of tumour size, histological type and grade (Bloom classification) and involvement of axillary nodes for all three endpoints. Additionally, young age appeared to be a significant risk factor for loco-regional disease-free survival. Prognostic subgroups were defined by the use of 3 main indicators. In node negative patients with T1 tumours the prognosis seemed to be good regardless of histological grade (80-90% 10-year disease-free survival), in T2 tumours the survival was significantly dependent on histological type and grade. In node positive patients increasing number of involved nodes and higher histological grade had an independent adverse effect on all three endpoints. The study demonstrates that classical, commonly available prognostic factors clearly distinguish subgroups with different prognosis, which may be helpful when deciding on the use of adjuvant local and/or systemic therapies.

Adult↗

PubMed1994

Comparative flow cytometric DNA analysis on fresh and paraffin-embedded tumor tissue in different neoplasms.

The results of flow cytometric DNA-analysis on fresh and paraffin-embedded tissue were compared in four various groups of tumors. The best correlation of the results was observed in the group of non Hodgkin's lymphomas. Comparative analysis of the ploidy on fresh and paraffin embedded tissue demonstrated discordance in particular in mammary carcinoma and malignant melanoma groups. The values of proliferative fraction assessed on fresh and paraffin embedded tissues were interrelated.

Breast Neoplasms↗

PubMed1994

[Second primary malignant neoplasms in patients treated radically for carcinoma of oral cavity, larynx and lungs].

About 1% of the patients with oral cavity, larynx, and lung cancer get second primary malignant neoplasms every year. For laryngeal cancer the percentage exceeds 10. Second primary tumors in oral cavity, larynx, and lung cancer patients are also tobacco-related neoplasms. Smoking cessation by patients with oral cavity, larynx, and lung cancer may have significant influence on the prognosis. Vitamin A (retinol) and its analogues are promising for human cancer prevention.

Humans↗

PubMed1993

Adjuvant progestagen therapy improves survival in patients with endometrial cancer after hysterectomy. Results of one-institutional prospective clinical trial.

A prospective study was conducted to determine the effectiveness of adjuvant hormonotherapy in endometrial cancer after surgery. Two hundred and five patients were randomly assigned to adjuvant progestagen treatment or were given no additional therapy. The follow-up was 5-years. We concluded that there was evidence of gain from adjuvant progestagen therapy in postoperative endometrial cancer. The group of patients who received progestagens had significantly longer survival than the control group without hormonotherapy (Logrank test; P < 0.001).

17 alpha-Hydroxyprogesterone Caproate↗

PubMedDate not supplied

[Predicting the incidence of malignant neoplasms in Cracow in the year 2000].

In connection with the data of the Cracov Tumor Registry concerning the 1970-1985 period and the population prognoses of the city of Cracov the expected incidence and the number of patients with most common malignant neoplasms in the year 2000 has been estimated. One can foresee the continuance of the decrease of the risk and incidence of malignant neoplasms of the stomach in both sexes and of cancer of the lung and breast in women. The incidence of malignant neoplasms in general as compared with the year 1985 will in the year 2000 increase by ca. 60% in men and by ca. 39% in women.

Adult↗