ABSTRACT
Although the inherited nature of some malignant and benign ocular tumors has been known for several generations, it has been viewed by many physicians as just another curiosity of their profession. Only since the second half of the 20th century has increased knowledge and understanding of the genetic background of these tumors evolved into practical tools in the clinical management of affected patients. Hereditary retinoblastoma has been known for many decades to be transmitted by a single autosomal dominant gene, but it has also been believed that only a small percentage of retinoblastomas are genetically transmitted. In the last decades, new studies into the nature of retinoblastoma have greatly improved genetic counseling, diagnosis, and even treatment of these patients. In addition, new cytogenetic studies performed in the United States, Canada, Japan, and some European countries have brought the subject of retinoblastoma into the forefront of all human cancer research.
