A prospective clinical parametric study comprising women afflicted by breast cancer and otherwise healthy participants was undertaken. The mean plasmatic concentration of putative leucine amino peptidase and nucleoside diphosphate phosphotransferase enzymatic complex in breast cancer cases was significantly elevated [43.9±2.8 μg ml⁻¹ (n=9)] when compared to those found in otherwise healthy women [8.07±0.14 μg ml⁻¹ (n=8)]. Women without images compatible with any tumours (n=13) had a mean concentration of 10.77±1.49 μg ml⁻¹. The mean value obtained in women with fibroadenomas was 10.15±0.81 μg ml⁻¹ (n=6) and with cystic fibrosis mastopathy 8.75±0.28 μg ml⁻¹ (n=7). The efficacy of a tandem quantitative biodiagnostic system as a parametric screening tool for the early detection of breast cancer is underlined, raising the possibility of increasing the cost effectiveness of current imaging non-parametric technologies.