The aim of this study is to collect data on Korean patients with borderline ovarian tumors.

The researchers retrospectively collected data on Korean patients with borderline ovarian tumors (BOTs) diagnosed, treated, and followed between November 1994 and February 2015 at institutions where placed in the Republic of Korea. And the researchers prospectively will collect data on all Korean patients with BOTs at institutions where placed in the Republic of Korea since March, 2015. If patients agree to participate in this KOBOT registry, patient's data (such as age, body mass index, preoperative findings, laboratory findings, radiologic findings, operative findings, pathologic findings, postoperative findings) will be collected in a research database. The research database will be updated, every 6 month, to include data on patient's disease outcome and follow-up care. Although most data will be collected form the medical record, patient may agin be contacted so that researchers can collection some data if it is not in the medical record.

Inclusion Criteria:

• Patients with borderline ovarian tumors (BOTs) diagnosed, treated, and followed between November 1994 and February 2015 at institutions where placed in the Republic of Korea.
• All patients undergoing gynecologic surgery for BOTs at institutions where placed in the Republic of Korea since March, 2015

Exclusion Criteria:

• Patients who did not receive primary treatment or follow-up for at least 6 months at each institution were excluded from analysis

Korean patients with borderline ovarian tumors (BOTs)