Introduction/Background Conditional relative survival (CRS) considers changes in prognosis over time and thus, may offer more useful estimates for survivors and clinicians. We aimed to investigate the CRS among patients with ovarian cancer with comprehensive stratification by various factors that influence survival probabilities.

Methodology This nationwide retrospective cohort study used data from the Korean Central Cancer Registry. We included 78,606 patients diagnosed with cervical cancer as their first cancer between January 1, 1997 and December 31, 2016. CRS and the conditional probabilities of death for the following 1 year were calculated stratified by age at diagnosis, histology, stage at diagnosis, year of diagnosis, and social deprivation index.

Results The 5-year relative survival rate at the time of diagnosis was 61.1% for all cases. The probability of surviving an additional 5 years conditioned on having already survived 1, 2, 3, 4, and 5 years after diagnosis was 65.0%, 69.5%, 74.6%, 79.3%, and 83.9%. Patients with poorer initial survival estimates (older, advanced stage) generally showed the largest increases in CRS over time. Patients aged ≥70 years had the highest probability of death in the first year after diagnosis (34.9%), but the conditional probability of death in the 2nd, 3rd, 4th, and 5th year declined abruptly to 14.7%, 9.2%, 6.0%, and 4.9%, respectively.

Conclusion The CRS rates for patients with ovarian cancer improved over time, particularly among patients with poorer initial prognoses. Our estimates can enable patients to make better informed decisions regarding follow-up care and their personal life.

Disclosures I have no conflicts of interest.