Therefore, we inquired (a) whether we can detect MACC1 and S100A4 mRNA transcripts in serum of ovarian cancer patients at a level that significantly differs from healthy controls and (b) whether MACC1 and S100A4 transcript levels at primary diagnosis and in the course of surgery and adjuvant chemotherapy could have the potential as liquid biopsy markers for ovarian cancer. The gene discussed is S100A4; the disease is ovarian cancer.