Orbital space-occupying lesions in Denmark 1974-1997.

. Purpose: To determine the frequency, distribution according to diagnosis and the recurrence frequency of orbital space-occupying lesions in Denmark, to determine sex and age of the patients and to establish a national orbital data register. Methods: All biopsied/surgically removed orbital lesions collected by Danish pathological departments during the period 1974–1997 were identified by SNOMED codes. In addition, in each case gender and age of the patients and number of recurrences were registered. Results: 965 orbital lesions from 841 patients were identified during the 24-year period. The incidence of orbital lesions increased significantly over the study period and at present about 80 cases/year are registered. The ratio benign/malignant lesion per year remained constant during the observation period. Lesions in children constituted a total of 152 (16%), the percentage of lesions in children being constant during the period. Malignant tumors comprised a total of 364 (45%) in adults and 34 (22%) in children. Malignant tumors were in adults distributed with 43% primary, 48% secondary invading and 9% metastatic tumors, and in children with 65% primary, 29% secondary invading and 6% metastatic tumors. Normal tissue was only found in 6% of the cases recorded. Conclusion: A registration of all histologically evaluated orbital space-occupying lesions in Denmark during a period of 24 years was performed and a national orbital database established. Orbital lesions are rare and primarily benign.