A method for detecting cancer in an individual comprising detecting a deletion in the nucleic acid sequence between residues 10743 and 14125 in mitochondrial DNA, obtaining a biological sample from the individual, extracting the mitochondrial DNA (mtDNA) from the sample, quantifying the amount of mtDNA in the sample having a deletion in the nucleic acid sequence between residues 10743 and 14125 of the mtDNA genome, and comparing the amount of mtDNA in the sample having the deletion to at least one known reference sample.