Considerations Regarding the Use of Blood Samples in the Proteomic Identification of Biomarkers for Cancer Diagnosis

Blood is the most common source of biomarkers for use in the diagnosis and prognosis of malignant disease. Utilizing proteomic technology for biomarker identification offers greatly increased sensitivity. Such an increase in sensitivity requires precise sample preparation to eliminate any bias in analysis. Here, issues concerning the use of blood, plasma and serum for proteomic analysis are summarized. The development of technologies for the early identification of malignant disease would greatly assist in treatment. Ovarian cancer is a leading example of the case in point. Its early, definitive diagnosis would be a major benefit as most patients present with advanced disease (1); early diagnosis (Stage I disease) results in a far more favorable outcome than with advanced Stage III or Stage IV disease (2, 3). Success depends on the development of a technology that is both sensitive and specific (4).