Increasing occurrence of urological cancers in Slovakia.

Similarly as in other developed countries of the world cancers of the upper and lower urinary tract are increasing also in Slovakia. Of greater importance are urological cancers in men participating recently worldwide with 17% on all newly diagnosed cancers. In women only 3% of all incident cases occur in urological sites. Data on incidence of urological cancers in the period 1968-1999 were derived from the National Cancer Registry, while those of mortality from the Statistical Office of the Slovak Republic. World standard population was used for the age-adjustment of both indicators. Temporal trends were evaluated using Poisson regression and computation of mean annual percent changes (MACP). Substantial and nearly parallel increase of incidence and of mortality has been observed for prostate cancer. Despite dramatic increase of testicular cancers incidence, corresponding mortality rates remained stable with the tendency to decrease recently. Incidence and mortality rates of urinary bladder cancer in men showed tendency to peaking while in women incidence increased and mortality showed tendency to stabilization. Incidence rates of kidney cancers increased in both sexes during the whole period, followed by slow increase of mortality at substantially lower levels. With the exception of mortality from testicular cancer all analyzed trends were statistically significant. In conclusion, only in the case of testicular cancer important reduction of mortality has been obtained despite dramatic increase of incidence. Reduction of smoking and improvement of industrial hygiene may influence the development of bladder cancer incidence and mortality. Limited resources for establishment of a concise cancer control program in this country do not allow to slow down in the near future the increase of incidence and mortality of prostate and kidneys cancers in Slovakia.

Lung cancer incidence rates by histologic type: an example of trends in Eastern Europe--Slovakia 1978-95.

During the period 1978-1995 43206 cases of lung cancer--37967 in men and 5239 in women--were recorded in Slovakia. Among 26240 microscopically confirmed cases in men squamous cell carcinomas were the most frequent (57.1%) followed by small cell carcinomas (18.3%) and adenocarcinomas (11.7%). In women from 3190 microscopically confirmed cases squamous cell carcinomas and adenocarcinomas had nearly the same frequency (31.9% and 32.2%, respectively), followed by small cell carcinomas (16.1%). In men after a marked increase of overall lung cancer incidence and mortality the rates started to flatten and even decline from the early 1990s. The main histologic types peaked in the late 1980s and declined thereafter but showed increase of percentage change when the rates at the beginning and the end of the studied period were compared; the highest one was marked for adenocarcinomas. The corresponding rates in women were much lower, but their increase was more pronounced than in men. Adenocarcinomas showed almost twofold increase in women during the first time-period of the study but after peaking in 1984-1986 they stabilized, while squamous cell carcinomas continued to increase also in recent years. The analysis of incidence rates by age groups showed that the initial increase and subsequent decrease of all microscopically confirmed cases in men as well as their gradual increase in women was influenced mainly by the trends of squamous cell carcinomas in younger age groups in men and in all age groups in women. Absence of higher increase and proportion of adenocarcinomas in Slovakia in both sexes could probably be explained by delayed introduction of filter tipped and low tar cigarettes.

Trends in the incidence of non-melanoma skin cancer in Slovakia, 1978-1995.

Non-melanoma skin cancer (NMSC) incidence in Slovakia in the period 1978-1995 was analyzed. A total of 38,629 microscopically confirmed NMSC cases (19,600 in males and 19,029 in females) were registered by the National Cancer Registry: 31,714 (82.1%) were basal cell carcinomas (BCC), 6,396 (16.6%) squamous cell carcinomas (SCC) and only 519 (1.3%) other NMSC. Age standardized rates of NMSC increased in the given period by 59.1% in males and 58.5% in females. The greatest increase was observed for BCC, 70.4% and 65.0% in males and females respectively, the smaller for SCC, 13.5 and 18.8%. In the period 1993-1995 age-standardized incidence rates per 100,000 were 38.0 for BCC, 6.7 for SCC and 45.5 for all NMSC in males and 29.2, 3.8 and 33.6, respectively in females. The observed marked increase of incidence with age was particularly pronounced for SCC. In both sexes, head and neck was the most common localization of BCC and SCC (84.2 to 74.7%), followed by trunk for BCC (17.0% in males and 10.8% in females) and by upper limbs for SCC (with 11.6% in males and 12.5% in females). Very fast increase of BCC incidence over time, its slower increase with age as compared to SCC incidence and body-site distribution suggest that BCC etiology is much more similar to melanoma etiology than SCC one. Registration of NMSC in relation to changes in possible risk factors (i.e. sun exposure/protection, ozone layer decrease) is important to study the mechanism of disease occurrence and to support public health interventions.

Larynx cancer in Slovakia and the role of anatomical subsites.

During the time period 1968-92, 6958 laryngeal cancers (6602 in men and 356 in women) were diagnosed in Slovakia and notified to the National Cancer Registry. We analysed long-term trends in incidence, mortality and survival. Mortality and incidence rates in Slovakian men rose rapidly until 1980 and more slowly subsequently. The mortality-to-incidence ratio initially was 40% and increased to 70% in the period 1985-88. A log-linear model showed that the more recent generations experienced the slowest increase in incidence. Incidence and mortality rates in women remained stable and did not exceed 1 per 100,000. The 5-year survival probability from invasive larynx cancer was 47%. Survival rates had shown no particular trend by year and age at diagnosis. The main finding was that 5-year survival from supraglottis cancer is 20% poorer than survival from glottis cancer. Supraglottis is the prevalent larynx subsite in countries with high larynx, oropharynx and oesophagus incidence rates. This supports the hypothesis that supraglottis cancer is more strongly linked to a synergistic effect of smoking and alcohol than glottis cancer.

Increasing occurrence of oropharyngeal cancers among males in Slovakia.

The gradual decline of oropharyngeal cancers in postwar period was followed by their rapid increase during recent two decades among males in Slovakia. Overall age-adjusted incidence rates of cancers of oral cavity and pharynx increased from 4.5 in 1968-1970 to 20.7 in 1990-1992 and corresponding mortality rates from 2.8 to 14.0 per 100,000 males. Oropharyngeal cancers have recently accounted for 6.5% of all newly diagnosed cancers yearly and present the fourth most frequent cancer site among males in this country. The cancers of tongue, floor of mouth, oropharynx and hypopharynx are responsible for the dramatic increase of this combined site in males. The culmination of the age-specific incidence and mortality rates of these cancers in the age groups 40-59 confirms the leading role of middle-aged men in their increase and dominant position. The occurrence of cancers of major salivary glands and nasopharynx in males, as well as the incidence and mortality rates of all oropharyngeal cancers in females remained very low and an unchanged (less than 1% of total). Increasing and extremely high incidence and mortality rates from oropharyngeal cancers among males in Slovakia require more effective primary prevention, above all substantial reduction of smoking.

Improving survival for childhood cancer in Slovakia.

Data from the National Cancer Registry of Slovakia were used to evaluate survival for 2,958 childhood cancer patients registered between 1968 and 1987 and aged 0-14 years at diagnosis. Actuarial survival rates were computed for children diagnosed in 4 successive 5-year periods and compared. Overall 5-year survival rose from 20% for the period 1968-1972 to 46% for the period 1983-1987. The increase was statistically significant in age groups 1-4, 5-9 and 10-14 years. Survival for children aged less than l year also increased slightly, but this was not statistically significant. In most of the major diagnostic groups, survival increased markedly. Five-year survival rose significantly for leukaemias, lymphomas, CNS neoplasms, Wilms' tumours, bone tumours, soft-tissue sarcomas and germ-cell tumours. Despite this progress, survival in Slovakia remains lower than the corresponding figures from registries in Western Europe and the United States.

Mapping in epidemiological studies and control of cancer: experiences from Slovakia.

This article reviews our experience with the use of the cancer atlas of Slovakia, published in 1989 which presented simultaneously the cancer incidence and mortality rates derived from national population-based cancer registries. Contrary to all expectations, the role of the environmental pollution was confirmed only for nonmelanoma skin cancer and arsenic exposure. Valuable information was obtained also for the study of dynamics of cancer distribution, which revealed a shift in the incidence of stomach cancer to the east and its replacement with colorectal cancer in the western part of the country. Of enormous importance for the comprehensive cancer care and control is the knowledge of incidence and mortality rates at the level of individual districts.

Epidemiological features of gastric and oesophageal cancers in Slovakia.

Data from Slovakia were analysed to determine whether, in accordance with observations made in western Europe and the United States, there is an increasing occurrence of tumours around the oesophagogastric junction. However, the increase in oesophageal cancers in this area was found to be attributable to squamous cell carcinomas. This is in keeping with observations made in central and eastern Europe of an increase in the incidence of tobacco- and alcohol-related cancers.

Thyroid cancer in Slovakia, 1968-1990: incidence, mortality and histological types.

Data on thyroid cancer incidence and mortality from the national cancer registry in Slovakia have been analysed for 1968-90, representing one of the first such descriptive epidemiological studies from Eastern Europe. The incidence of thyroid cancer has increased over this period, particularly among women, from approximately 1.5 to 2.5 per 100,000. These increases occurred primarily in papillary carcinomas, and to a lesser extent follicular carcinomas; the greatest proportional increase was in the younger age groups. In contrast to data reported from other areas, mortality also increased over the same period. The reasons for such increases are not evident, but the increases in mortality certainly indicate the potential for improvements in the treatment of thyroid cancer in Slovakia, as well as further study on the aetiological factors involved in the disease.

Oral and pharyngeal cancer incidence in Slovakia 1968-1989.

Slovakia currently has one of the highest incidence rates of oral cancer in Europe. Incidence data from the Slovakian Cancer Registry relating to oropharyngeal cancer are analyzed for the period 1968-1989 to examine trends in the incidence of these malignancies, representing the first such reported time-series from Central Europe. Over this period, rates in males have increased from 4.5 per 100,000 in 1968-1970 to 17.9 per 100,000 in 1987-1989, with more marked increases noted amongst middle-aged males (35 to 64 years), among whom rates have increased from 6.8 to 47.9 per 100,000 over the same period. Rates in women have been relatively low and stable. Changes in rates in men follow a period during the 1950s and 1960s when there was a marked increase in alcohol and tobacco consumption. The magnitude of the increases have resulted in oropharyngeal cancer becoming an important public health problem in Slovakia and emphasizes the importance of measures to prevent further increases in the consumption of tobacco and alcohol.

The role of the registry in the study of relation between cancer and environment experiences from Slovakia.

Highly complete and detailed data on cancer incidence collected in National Cancer Registry of Slovakia in the years 1968-1988 contributed largely to the study of the relations between cancer occurrence and environment. The study of temporal trends of age-adjusted rates revealed the rapid increase of overall cancer incidence and mortality rates in males influenced mainly by extreme increase and high proportion of lung cancer. The lower but increasing overall incidence rates in females could be related to the increase in breast, other skin and genital organs cancers, while the stabilized mortality trends were caused by improving prognosis of these major cancers in females. The possible role of environmental factors in adults could be stressed also by the temporal trends of childhood malignancies which remained fairly stable during the same period. The role of environmental factors in cancer etiology is further documented with the dramatically increasing incidence of malignant skin melanoma caused probably by the overexposition to the sunlight and with prevailing incidence of the majority of cancer sites in urban areas. Finally, the significantly increased incidence rates of other skin cancers are shown in two districts and in both sexes in relation to the environment, highly polluted with arsenic.

[Incidence of malignant tumors in Slovakia. I. Levels and trends 1968-1989]. / Incidencia zhubných nádorov na Slovensku. I. Hodnoty a trendy v rokoch 1968-1989.

In the period from 1968-1989 an increase in the overall incidence of malignant tumors was recorded in men. Of the individual localizations a particularly marked increase was recorded in tumors of the lung, followed by tumors of the oral cavity, pharynx, esophagus, pancreas, urinary bladder, kidney (related to smoking), as well as of the testis and prostate gland. In women the values of overall incidence were lower and the trends were relatively stabilized. This is due to the relatively slow increase in the incidence in cancer of the breast and female reproductive organs and to the slight increase in cancer of the lung. Cancer of the kidney, urinary bladder and pancreas exhibited increased incidence. Low values, stabilized and even decreasing trends were recorded in the incidence of cancer of the oral cavity, pharynx, esophagus, and larynx, as compared to values found in men. In both sexes the incidence of cancer of the stomach showed a pronounced decrease, while the incidence of cancer of the colon and rectum was increasing. A smaller or greater rise was found also in the incidence of tumors of the hematopoietic and lymphatic tissues (except Hodgkins's disease). The trends observed in the incidence of malignant tumors in Slovakia are suggestive of their uncontrolled course, not affected by preventive measures. Yet the findings provide important information for directing the measures so as to aim at localizations of priority. (Tab. 2, Fig. 7, Ref. 20.)

Survival rates for childhood malignancies in Slovakia.

Survival rates (SR) for population-based series of 1564 cases of cancer in children aged 0-14, diagnosed during the decade 1978-1987 in Slovakia and derived from the National Cancer Registry, were examined. The overall 5-year SR (all types of childhood malignancies combined) was 49.8%. Different SR were ascertained for leukemias -43.8%, lymphomas -59.1%, CNS tumors -42.7% and for other remaining diagnostic groups and subgroups of childhood malignancies. Generally, the SR were slightly better for girls than for boys. Cancer patients being diagnosed during the first two years of age showed worse prognosis with a 5-year survival rate of 36.8% as compared to 52.6% for children aged 2-14 at diagnosis. Differences in 5-year survival were also found between urban and rural areas: 56.8% and 48.8%, respectively. The 5-year SR increased during the study period from 48.5% for 1978-1982 to 50.0% for 1983-1987. Comparison of SR from Slovakia with the corresponding rates observed recently in some developed countries indicated possibilities to improve prognosis of childhood malignancies in this country.

Development of registration and cancer incidence rates and trends in Slovakia.

The development of cancer registration, from the introduction of obligatory notification and the establishment of National Cancer Registry of Slovakia, is described. The activity of the registry is illustrated by the list of publications which have emanated from this institution in recent years. The survey is completed by the analysis of the incidence rates of individual cancer sites in the last 5-year period (1984-1988) and by their trends in the decade 1979-1988. The positive role of the registry in the establishment of a cancer control programme and the investigation of cancer epidemiology is stressed.