According to a recent article published in The Lancet, a type of genetic testing called comparative expressed sequence hybridization (CESH) appears to accurately predict the risk of a cancer relapse in patient with Wilms’ tumor.
Wilms’ tumor is the most common cancer of the kidney in children. It affects approximately one in 10,000 children. Treatment for Wilms’ tumor typically includes surgery, chemotherapy and/or radiation therapy. Although many patients are cured following therapy, some experience a cancer relapse. Researchers have been evaluating disease characteristics to predict which patients are at a higher risk for a relapse, so treatment can be individualized, with more intense treatment given to patients at a high relapse risk and less treatment given to patients at a low relapse risk.
Researchers from England recently conducted a small study to evaluate genetic associations between patients with Wilms’ tumor who relapsed versus those who were cured. CESH is a test that utilizes a small tissue sample from the tumor to analyze which genes are “turned on” or expressed in certain regions of a chromosome. Chromosomes are structures found inside cells which contain all of an individual’s DNA. This trial included 18 patients that were followed for a minimum of 3 years, since over 90% of cancer recurrences of Wilms’ tumor occur within the first 3 years following therapy. All of the 8 patients who relapsed demonstrated overexpression of genes in the chromosome region referred to as 1q. Conversely, none of the 10 patients who were cancer free demonstrated an overexpression in chromosome 1q. There were two regions on chromosome 1q that demonstrated overexpression, so researchers speculate that at least two different genes are related to a cancer recurrence in Wilms’ tumor.
These researchers concluded that overexpression of chromosome 1q, as detected through CESH, appears to accurately determine the risk of a relapse in patients with Wilms’ tumor. Patients at a high risk for a cancer relapse can be treated more intensely in order to reduce this risk, while patients at a low risk can be treated less aggressively and thus reduce the long-term side effects from treatment. Future clinical trials that include a larger patient population to further confirm these findings are warranted. Parents whose child has been diagnosed with Wilms’ tumor may wish to speak with their physician about the risks and benefits of participating in a clinical trial further evaluating CESH or other promising screening approaches.
Reference: Lu Y-J, Hing S, Williams R, et al. Chromosome 1q expression profiling and relapse in Wilims’ tumour.
The Lancet. 2002;360:385-386.