Of these six proteins, two in particular proved to be of interest based on previously reported biological significance in the literature for ovarian cancer and other types of cancer: protein S100-A8 and cystatin A. Protein S100-A8 (m/z 10,835 ± 40 ppm, supplemental Fig. S1) was found to be downregulated over time in vaginal lavages as tumor burden increased, whereas cystatin A (m/z 11,007 ± 30 ppm) was found to be upregulated over time. Here, CSTA is linked to ovarian cancer.