Epidemiology of primary CNS tumors in Greece

Doctoral Dissertation uoadl:2858602 478 Read counter

Unit:
Τομέας Κοινωνικής Ιατρικής - Ψυχιατρικής και Νευρολογίας
Library of the School of Health Sciences
Deposit date:
2019-02-11
Year:
2019
Author:
Papathoma Paraskevi
Dissertation committee:
Ελένη Πετρίδου, Καθηγήτρια, Ιατρική Σχολή, ΕΚΠΑ
Λεωνίδας Στεφανής, Καθηγητής, Ιατρική Σχολή, ΕΚΠΑ
Αχιλλέας Χατζηιωάννου, Καθηγητής, Ιατρική Σχολή, ΕΚΠΑ
Παναγιώτα Σουρτζή, Καθηγήτρια, Τμήμα Νοσηλευτικής, ΕΚΠΑ
Γεώργιος Παρασκευάς, Αναπληρωτής Καθηγητής, Ιατρική Σχολή, ΕΚΠΑ
Μαρία Μοσχόβη, Επίκουρη Καθηγήτρια, Ιατρική Σχολή, ΕΚΠΑ
Μαρία Καντζανού, Επίκουρη Καθηγήτρια, Ιατρική Σχολή, ΕΚΠΑ
Original Title:
Επιδημιολογία των πρωτοπαθών όγκων κεντρικού νευρικού συστήματος στην Ελλάδα
Languages:
Greek
Translated title:
Epidemiology of primary CNS tumors in Greece
Summary:
Primary central nervous system (CNS) tumors comprise a heterogeneous group of
malignancies. The epidemiology of these neoplasms is still considered inconclusive
and reports from countries with comparable epidemiological data reveal spatial and
temporal variations, which need to be further investigated.
Following the completion of the first 5-year nationwide childhood registration in
Greece, the quality of which follows the IARC criteria, patterns and temporal trends
of childhood CNS tumors are presented along with comparison to data from several
regional and national registries in the Region of Southern and Eastern Europe (SEE).
In the absence of data for greek Adolescents and Young Adults (AYAs),
epidemiological data of CNS tumors of this distinct age group in the SEE area were
examined and comparisons with the publicly available US data from SEER were
undertaken.
In Greece, for the first study period 2009-2014, the age-adjusted incidence rate of
malignant childhood CNS tumors was 22.4 per million children, which was
comparable with the average incidence rate observed in the 12 participating SEE
Registries (23 per million children). During the whole study period (1983-2014), a
slight predominance of males was observed, and the incidence rates were declining
gradually with the age. Astrocytomas were overall the most common subgroup (30%),
followed by embryonal tumors. The latter was the predominant subgroup in six
registries, including Greece. For the further evaluation of the observed bidirectional
temporal trends and the various geographical disparities, factors affecting the
registration quality should be considered.
Substantial variations in mortality and survival were observed among the 14 SEE
participating registries. In most countries, mortality time trends were rather stable,
except for Bulgaria, which demonstrated the highest rate during the initial registration period followed by a steadily decreasing annual mortality rate. A steep decrease in
survival was evident before the second year of follow-up. After adjusting for
diagnostic groups, age, gender and the year of diagnosis, Greece presented higher
survival compared to the other contributing countries, although the follow-up period
was short. Irrespective of the country, rural residence was found to impose substantial
adverse repercussions on survival.
In the age group of AYAs, the overall age-adjusted incident rate of malignant CNS
tumors was significantly higher (28.1 per million) in SEE (11.438 cases for the period
1990-2014) compared to SEER (24.7 per million, 13.573 cases for the period 1990-
2012). Astrocytomas comprised almost half of the cases in both regions, albeit the
higher proportion of unspecified cases in SEE registries (30% versus 2.5% SEER).
We observed similar age and gender distributions across SEE and SEER with a male
to female ratio of 1.3 and an overall increase of incidence by age. The observed
increase in incidence rates, documented in four SEE registries, namely Greater
Poland, Portugal North, Turkey-Izmir and Ukraine, could potentially be the result of
improvements in registrations. Finally, a decreasing trend in Croatia (-2.5%), and a
rather stable rate in SEER (-0.3%) were noted.
Mortality rates in SEE (range: 11.9-18.5 deaths per million) were higher overall than
the SEER rate (9.4 deaths per million), with decreasing trends in both regions.
Survival rates increased during a comparable period (2001-2009) in SEE and SEER.
The 5-year survival rate was considerably lower in the SEE registries (46%) versus
SEER (67%), mainly because of the extremely low rates of Ukraine; this finding was
consistent across age groups and diagnostic subtypes. The highest 5-year survival
rates were recorded for ependymomas (76% SEE, 92% SEER), and the worst were
recorded for glioblastomas and anaplastic astrocytomas (28% SEE, 37% SEER).
Advancing age, male sex, and rural residency at diagnosis adversely affected
outcomes in both regions.
In conclusion, epidemiological data on CNS tumors from the NARECHEM-ST and
other registries in the SEE area are reported for the first time in this thesis. The results
of the Greek registration are comparable with those reported by other developed
European countries, whereas the observed heterogeneity in registration practices and
incidence rates of childhood CNS tumours across the SEE area necessitates further investigation. The cross-country mortality and survival variations possibly reflect
suboptimal levels of health care delivery and cancer control in some regions of SEE.
Regarding the AYAs age group, the higher incidence rates of malignant CNS tumors
recorded in the SEE area compared to the United States of America could be also
explained by possible environmental and/or genetic factors. The considerable
outcome discrepancies between some registries and the overall worse prognosis of
patients residing in rural areas reflect inequalities in health care delivery. Albeit the
complexity of the interpretation of temporal trends affected by registration
improvements, no significant increase in incidence rates appears while survival rates
improve with some time lag in the SEE area. The results of the thesis can contribute
to an evidence-based health-care planning in order to diminish inequalities for a
disease with an unfavorable outcome compared to other cancers affecting young age
groups.
Main subject category:
Health Sciences
Keywords:
Epidemiology, Tumours, CNS
Index:
No
Number of index pages:
0
Contains images:
Yes
Number of references:
174
Number of pages:
196
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