RESUMEN
Congenital tumours and tumour-like lesions represent a group of rare disorders in both veterinary and human medicine that arise from tissue remnants and are detected during pregnancy or within the first 2-3 months of life. Different forms of congenital tumours and congenital tumour-like lesions have been reported in calves and their development is poorly understood. They often pose a diagnostic challenge and the referring nomenclature occasionally may be equivocal. Previous reports regarding tumour-like lesions, soft tissue tumours, vascular tumours, round cell tumours and neoplasms of the nervous, peritoneum and urogenital systems are summarized in this review, and the role of genetic factors in the development of these conditions is discussed.