Loss of heterozygosity on chromosome 13 and its association with delayed growth of retinoblastoma

✍ Scribed by Mitsuo V. Kato; Kanji Ishizaki; Yosuke Ejima; Akihiro Kaneko; Hiroshi Tanooka; Masao S. Sasaki

• Book ID: 102868882
• Publisher: John Wiley and Sons
• Year: 1993
• Tongue: French
• Weight: 751 KB
• Volume: 54
• Category: Article
• ISSN: 0020-7136
• DOI: 10.1002/ijc.2910540609

✦ Synopsis

Loss of heterozygosity (LOH) on chromosome I 3 and the age of patients at operation were studied in 46 cases of retinoblastoma (RB) tumors, of which 25 were hereditary and 21 were non-hereditary. The frequency of LOH was 70% for all informative tumors, but significantly higher in non-hereditary tumors (90%) than in hereditary ones (52%). Our results suggest that LOH might be involved in the initial somatic events in nonhereditary tumors. Age at operation of patients with hereditary tumors was significantly lower than that of patients with non-hereditary tumors. Even when tumors associated with a family history were omitted from among the hereditary cases, the difference was still significant. In the case of hereditary tumors, age at operation of LOH-negative patients was significantly lower than that of LOH-positive patients. When tumors associated with a family history were omitted, the difference was still significant. The delay in development of LOH-positive tumors suggests that LOH for one chromosome 13 may be disadvantageous with respect to growth of RB tumors.