Characterization of Conditional Disease-Free Survival in Patients With Ovarian Cancer


Key Points

  • Conditional disease-free survival increased from 64% to 98% after 1 to 5 years of survival.
  • Conditional disease-free survival increases were greatest in patients with poorer initial prognosis.

In a study reported in the Journal of Clinical Oncology, Kurta et al calculated conditional disease-free survival estimates among ovarian cancer patients, showing that odds of remaining disease free improve with a longer disease-free period from initial remission.

Improved Conditional Disease-Free Survival Over Time

The study involved 404 patients form the Hormones and Ovarian Cancer Prediction case-control study who had achieved remission after diagnosis of ovarian, fallopian tube, or peritoneal cancer.

Median disease-free survival was 2.54 years (range = 0.03–9.96 years), and 3-year disease-free survival was 48.2%. The probabilities of surviving an additional 3 years without recurrence after surviving 1, 2, 3, 4, and 5 years were 63.8%, 80.5%, 90.4%, 97.0%, and 97.7%, respectively.

Greatest Increase in Women With Poorer Baseline Prognosis

Initial differences in 3-year disease-free survival according to age, stage, histology, and grade decreased over time. For example, whereas 3-year disease-free survival estimates ranged from 28.8% to 95.2% for histology subgroups at baseline, the range of estimates according to subgroup for patients surviving 5 years was 90.9% to 100%. The greatest increases in the conditional 3-year disease-free survival estimates were observed in older women and those diagnosed with stage III/IV disease, serous tumors, and poorly differentiated tumors.

The investigators concluded: “[Disease-free survival] estimates for patients with ovarian cancer improved dramatically over time, in particular among those with poorer initial prognoses. Conditional [disease-free survival] is a more relevant measure of prognosis for patients with ovarian cancer who have already achieved a period of remission, and time elapsed since remission should be taken into account when making follow-up care decisions.”

Brenda Diergaarde, PhD, of University of Pittsburgh Cancer Institute, is the corresponding author for the Journal of Clinical Oncology article.

The study was supported by grants from the National Institutes of Health. The study authors reported no potential conflicts of interest.

The content in this post has not been reviewed by the American Society of Clinical Oncology, Inc. (ASCO®) and does not necessarily reflect the ideas and opinions of ASCO®.