Objectives At present there is no predictive value univocally associated with the success of chemotherapy. Biomarkers produced by ovarian cancer (HE4 and Ca125) could have a good prognostic significance. The aim of this study is to prove the ability of biomarkers to identify patients with the highest risk of not optimal response during the chemotherapy and to predict which patients will most probably develop recurrence of disease.

Methods We analyzed 78 patients with EOC who underwent surgery in the biennium 2016–2017. All the patients performed chemotherapy after surgery or interval debulking surgery following neoadjuvant therapy. Serum levels of HE4 and Ca125 were measured at the diagnosis and at each cycle of chemotherapy. We established the degree of response to the treatment by CT-scan and the patients were followed up (FU median: 10 months). The parameters PFS and DFS were related to serum levels of biomarkers.

Results The average markers values became both negative at the fourth cycle in the patients with good response to chemotherapy. HE4 compared earlier than Ca125. The parameters that best correlated with a long PFS were: negativization of the marker after the third cycle of chemotherapy (HE4: OR 5.5; Ca125: OR 9.1) and biomarker serum levels lower than the mean value in the affected population at the time of diagnosis (HE4: OR 3.4; Ca125: OR 3.7).

Conclusions We can conclude that the monitoring of HE4 and Ca125 during chemotherapy, especially at the third cycle, is recommended, because their variation is a good prognostic factor.