Can mitochondrial DNA mutations in circulating white blood cells and serum be used to detect breast cancer?

Circulating mitochondrial DNA (mtDNA) affected by mutations have been detected in melanoma, prostate cancer, and digestive neoplasms involving the pancreas, liver, and the colon. We sought to detect such mutations in women with breast cancer to assess if the method could be used to aid in the diagnosis of breast cancer. Blood was collected and mtDNA extracted; 27 samples included 14 patients who had breast cancer and 13 healthy controls. White blood cells and serum were separated. The mitochondrial D-loop region was amplified using PCR followed by automated DNA sequencing. The collected data was analyzed with computer software to detect both polymorphisms and mutations. mtDNA sequencing was successful in 93% of the samples (n=23). No mutations were found in any of the study groups. Polymorphisms were detected in all specimens, three of which had not been previously reported. The method used did not detect mtDNA mutations in the blood of women with breast cancer, but was extremely sensitive in polymorphism detection.