Epidemiology of central nervous system tumors in Labin area, Croatia, 1974-2001

Aim. To establish the incidence of tumors of the central nervous system (CNS) in the population of Labin area in Istria, Croatia, characterized by very little population migration. Method. We retrospectively analyzed data on 175 patients (102 men and 73 women) diagnosed with CNS tumor according to the Word Health Organization´s diagnostic criteria in the period 1974-2001. Patient data were retrieved from multiple sources: files of general practitioners in Labin area ; registers of admissions and discharges of the Pula General Hospital and Rijeka University Hospital Center ; and medical records of the Hospital Departments of Neurology, Surgery, Neurosurgery, Oncology and Radiotherapy, and Pathology. Annual incidence, anatomic location, and pathohistological classification of CNS tumors were determined, as well as age at disease onset. Results. Out of 175 subjects, 95 had primary CNS tumors and 80 had metastases. Intravcranial tumors were found in 88.4% of patients with primary CNS tumors (annual incidence, 11.8/100, 000 population) and intraspinal in 11.6% of patients (annulal incidence, 1.6/100, 000). Similar distribution was observed for CNS metastases (70 intracranial vs 10 intraspinal), with annual incidence of 9.9 and 1.4/100, 000 respectively. The most frequent intrcranial tumors were those of neuroepithelial tissue, accounting for 58.3% of all CNS neoplasms (annulal incidence, 6.9/100, 000 population). The most frequent intraspinal tumors were tumors of the meninges (54.5%). There was no particular temporal clustering of CNS tumors. The age at disease onset corresponded with that reported in the literature: 50.5 (SD 17.0) years for primary intracranial tumors, and 59.7 (SD 12.2)years for primary intraspinal tumors. Conclusion. Primary CNS tumors showed high, but temporally stable incidence in population of Labin area over the last 27 years, indicating that the alleged increase in CNS tumors incidence was not true.