Early Detection of Relapse in Ovarian Cancer Using Capillary Home-sampling and a Multiplex Protein Biomarker Test - a Pilot Study

Early detection of relapse in ovarian cancer using capillary home-sampling and a multiplex protein biomarker test - a pilot study

PURPOSE AND AIMS Epithelial ovarian cancer (EOC) is the deadliest of all gynecologic cancers, with 700 incident cases per year in Sweden. Even though almost three out of four women with EOC relapse within 2-3 years, there is a striking lack of prospective trials on optimized follow-up after EOC treatment. The research group have previously identified a plasma marker protein panel with high accuracy for ovarian cancer diagnosis and follow-up. The aim with this pilot study is to validate the protein panel for its capacity to detect early relapse in symptom-free patients in a user-friendly, non-invasive way i.e., a home-administered capillary sampling. Further, the results will be the foundation for a forthcoming national prospective randomized trial (RCT) - the FOLL-OV trial.

SURVEY OF THE FIELD/PRELIMINARY RESULTS One of the main purposes with a follow-up program is to find cancer relapse at an early stage and thereby improve the patient's chance of successful treatment and prolonged survival. Yet, there is a striking lack of prospective studies in the field.

A recent RCT demonstrated eight months prolonged overall survival when treated with surgery at first relapse, compared to chemotherapy alone, however, the survival benefit was limited to women where complete surgical resection was achieved (3). Hence, it has become more important than ever to detect relapse as soon as realistically possible, when the tumor burden is limited.

As of present, the Swedish National Guidelines for EOC recommend follow-up 3-4 times/year during the first two years after completed treatment. The follow-up consists of physical (and gynecologic) examination, transvaginal ultrasound, and is many times complemented with the EOC biomarker CA125, but this is optional. CA125 is an unspecific marker, and not elevated in all types of EOC. In a Cochrane review evaluating follow-up strategies of women with EOC, only one RCT was included, and thus further RCTs are needed to evaluate different types of follow-up strategies, using outcomes such as survival, quality of life (QoL), cost and psychological effects. Importantly, in two recent retrospective studies, almost no relapses were detected exclusively on physical examination and the need for regular in-clinic visits were questioned in favor of virtual meetings with a review of symptoms and measurements of tumor marker.