Press Release: Intervention Studies That Use Cancer Patients from High-Risk Clinics May Be Subject to Bias

Extract

Many studies have tried to evaluate the effects of interventions to reduce cancer risk, such as tamoxifen therapy or prophylactic surgery, among patients that carry a mutation that increases their risk of cancer. However, some of the studies that use subjects from clinics that care for people at high risk of the disease may be subject to serious selection bias, according to a commentary that appears in the August 18 issue of the Journal of the National Cancer Institute.

Researchers who want to study the efficacy of interventions meant to reduce cancer risk in people who carry cancer-predisposing mutations, such as the BRCA1 and BRCA2 mutations for breast and ovarian cancers, face several challenges. Recruiting enough patients for a study can be difficult and expensive. In addition, patients who carry these mutations are rare and are often identified only after someone in their family has developed the cancer. Clinics that serve patients at high risk of developing these cancers can therefore be a tempting source of study participants.