Researchers in Cleveland Clinic’s Genomic Medicine Institute have found a strong correlation between large head circumference and cancer risk in patients with Cowden syndrome.
Published in the December 2010 issue of the journal Gastroenterology, the research focused on 127 patients who carry the genetic mutation that causes Cowden syndrome, which is associated with an increased risk of breast, thyroid and uterine cancers. Among these patients, large head circumference was the most common clinical trait.
“What this means is that people with big heads – defined as greater than 58 centimeters in men and 57 centimeters in women – should see a genetic counselor to determine whether they should be screened for colon, breast, thyroid and uterine cancers,” said lead researcher Charis Eng, MD, PhD, Hardis Chair of the Genomic Medicine Institute in Cleveland Clinic’s Lerner Research Institute.
Prior to Cleveland Clinic’s research, the medical literature estimated that just 25 percent of Cowden patients had large head circumferences. This study, though, found a much higher correlation, with 74.8 percent of the Cowden patients exhibiting large head size.
The study found a similar association with colon polyps. Before this study, colon polyps were not seen as a strong indicator of Cowden. However, the Cleveland Clinic study found that the presence of gastrointestinal polyps in these patients signifies increased risk of early-onset colorectal cancer that warrants routine colonoscopies starting at age 35, instead of at age 50 as recommended for the general population.
“Before these findings, I told my patients that there’s no need for unusually aggressive colon cancer screenings,” Eng said. “As we can see now from our research, however, we need to start screening these patients for colon cancer in their early- to mid-30s at the latest – and it should be annual screenings, not every 10 years.”
Cowden syndrome affects about 1 in 200,000 people, although the exact prevalence is unknown because it can be difficult to diagnose. The Cleveland Clinic study may improve diagnosis by including gastrointestinal polyps and head circumference among the diagnosis criteria. Under previous guidelines, 16.5 percent of this study’s patients would have erroneously escaped Cowden diagnosis upon enrollment.
The study also links mutations of the PTEN gene – a known cause of Cowden syndrome – to an increased risk of early-onset colorectal cancer at a rate that is 200-times as common as that of the general population.
The current study is the largest, most targeted study to date regarding the evaluation of benign and malignant growths in the GI tract of Cowden patients.
About Cleveland Clinic
Cleveland Clinic, located in Cleveland, Ohio, is a not-for-profit multispecialty academic medical center that integrates clinical and hospital care with research and education. It was founded in 1921 by four renowned physicians with a vision of providing outstanding patient care based upon the principles of cooperation, compassion and innovation. U.S.News & World Report consistently names Cleveland Clinic as one of the nation’s best hospitals in its annual “America’s Best Hospitals” survey. About 2,100 full-time salaried physicians and researchers and 11,000 nurses represent 120 medical specialties and subspecialties. In addition to its main campus, Cleveland Clinic operates nine regional hospitals and 15 Family Health Centers in Northeast Ohio, Cleveland Clinic Florida, the Lou Ruvo Center for Brain Health in Las Vegas, Cleveland Clinic Canada, and opening in 2012, Cleveland Clinic Abu Dhabi. In 2009, there were more than 4.6 million visits throughout the Cleveland Clinic health system and 170,000 hospital admissions. Patients came for treatment from every state and from more than 100 countries. Visit us at www.clevelandclinic.org.
About the Lerner Research Institute
The Lerner Research Institute is home to Cleveland Clinic’s laboratory, translational and clinical research. Its mission: to promote human health by investigating in the laboratory and the clinic the causes of disease and discovering novel approaches to prevention and treatments; to train the next generation of biomedical researchers; and to foster productive collaborations with those providing clinical care. The total annual research expenditure was $272 million in 2009 (including $100 million in federal funding). More than 2,000 people (including ~200 principal investigators, 290 postdoctoral fellows, and 185 graduate students) in 11 departments work in research programs focusing on cardiovascular, cancer, neurologic, musculoskeletal, allergic and immunologic, eye, metabolic, and infectious diseases. The Institute includes more than 700,000 square feet of space. Institute faculty oversee the curriculum and teach students enrolled in the Cleveland Clinic Lerner College of Medicine of Case Western Reserve University – training the next generation of physician-scientists, and they participate in multiple doctoral programs, including a new Molecular Medicine PhD Program supported in part by the Howard Hughes Medical Institute.
Dan Doron, [email protected], 216-636-5874
Tracy Wheeler, [email protected], 216-444-4235