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.