Thursday, September 1, 2016
Colon cancer in African American patients is a different disease molecularly than it is in whites
Case Comprehensive Cancer Center researchers, a research collaboration which includes University Hospitals Seidman Cancer Center and Case Western Reserve University, who in 2015 identified new gene mutations unique to colon cancers in African Americans, have found that tumors with these mutations are highly aggressive and more likely to recur and metastasize. These findings partly may explain why African Americans have the highest incidence and death rates of any group for this disease. The study found 15 genes in African Americans that are rarely or never detected as mutated in colon cancers from whites. The current study investigated the outcomes associated with these mutations in African American colorectal cancer. The researchers examined 66 patients who had stage I - III colorectal cancer and found that those patients positive for the mutations had an almost three times higher rate of metastatic disease, and stage III patients positive with mutations were nearly three times more likely to relapse compared to patients without the mutations. "This study is significant because it helps shed further light on why colorectal cancers are more aggressive in African Americans compared to other groups," said the study's senior author Joseph E. Willis, MD, Chief of Pathology at University Hospitals Case Medical Center and Professor of Pathology at Case Western Reserve School of Medicine. "While mortality rates for Caucasian men with colorectal cancer have decreased by up to 30%, they have increased by 28% for African American men since 1960," said Dr. Willis, who is also director of tissue management in the Case Comprehensive Cancer Center. These findings and the earlier study only became possible because of technological advances in gene sequencing and computational analysis. These studies ultimately involved review of 1.5 billion bits of data.