Bevacizumab in retinopathy
Cancer treatment bevacizumab could replace laser surgery as a treatment for some forms of diabetic retinopathy, a study in Venezuela has suggested.Focal laser treatment is usually used to treat patients with diabetic macular oedema, a manifestation of diabetic retinopathy and the most common cause of moderate vision loss in people with diabetes. However, researchers have begun to examine drug treatments, because although laser treatment can reduce vision loss, it does not usually lead to an improvement in visual acuity.
In addition, diffuse diabetic macular oedema is often resistant to laser and other standard treatments.
Bevacizumab is an antibody directed against vascular endothelial growth factor. It is currently indicated for the treatment of patients with cancers of the breast, colon, kidney, lung and rectum.
In the study, researchers gave the drug as an intravitreal injection to 115 patients with diabetic macular oedema, 24 of whom had two eyes treated. Improvements in visual acuity were seen within one month. After two years, patients’ vision had improved in 51.8 per cent of cases and 91.7 per cent of eyes were either stable or improved.
The study was conducted by Dr Fernando Arevalo of the Caracas Central Ophthalmologic Clinic in Venezuela and colleagues from the Pan-American Collaborative Retina Study Group. They said the results of the study were ‘very promising’ and required further investigation.
‘This new treatment method may replace or complement focal or grid laser photocoagulation,’ they said. Combination therapies, using both bevacizumab and laser therapy, should also be considered, they suggested.
However, the researchers added that therapies using bevacizumab and other drugs remain at an experimental stage. ‘We should all consider laser therapy for patients with diabetic macular oedema while we await advances and better outcomes from new therapies still under investigation,’ they said.
Arevalo JF, Sanchez JG, Wu L et al for the Pan-American Collaborative Retina Study Group (PACORES). Ophthalmology online 2009, doi:10.1016/j.ophtha.2009.03.016
Ovarian cancer gene discovered
A gene mutation that increases the risk of ovarian cancer has been found by scientists from Cancer Research UK.
Researchers from the Genetic Epidemiology Unit at the University of Cambridge and UCL found that women’s ovarian cancer risk was increased by one-fifth if one chromosome carried the variant DNA. Approximately 40 per cent of women in the UK carry one copy.
The study analysed 8,800 women with ovarian cancer and 12,500 without the disease across the UK. The risk of developing ovarian cancer was increased by 40 per cent for women carrying the variant genetic coding on both chromosomes.
Ovarian cancer is the fifth most common cancer in women in the UK, with 130 women diagnosed every week.
Dr Lesley Walker, director of cancer information at Cancer Research UK, said: ‘This research could lead to new approaches to treat or prevent the disease.’ Professor Paul Pharoah, who led the study, said the hunt was on to find the rest of the genes that make up the risk.
Song H, Ramus SJ, Tyrer J et al. Nature Genetics online 2009, doi:10.1038/ng.424.