Epithelial borderline ovarian tumors (BOT) are distinctive from benign tumors and carcinoma. They occur in younger women more often than carcinoma, and there is some difficulty making correct diagnosis of BOT. Two subtypes of BOT, serous and mucinous borderline tumor have different characteristics and very different clinical behavior. Serous borderline tumor (SBT) with micropapillary pattern shows more incidence of extra ovarian disease and often coexists with invasive implant. SBT with micropapillary pattern in advanced stage has showed a worse prognosis than typical SBT. Huge mucinous borderline tumors have histologic heterogeneity, and the accuracy of frozen section diagnosis is relatively low. Extensive sampling is required to reach a correct pathological diagnosis. Mucinous adenoma (intestinal type) also runs the risk of recurrence after cystectomy, or intraoperative rupture of cyst. Laparoscopic procedure for BOT has not increased the risk of recurrence. Fertility preserving procedures are generally accepted, except in advanced stage SBT with invasive implants. Only cystectomy shows a significant risk of recurrence. Re-staging surgery and full staging surgery is not necessary for all BOT. We should not attempt to treat them uniformly, by the single diagnosis of "borderline tumor". It depends on histologic type. Close communication with the pathologist is necessary to gain more detail and ask more pathological samples in order to make the optimal treatment strategy for each individual patients.
Keywords: Borderline ovarian tumor; Laparoscopy; Mucinous borderline tumor; Recurrence; Serous borderline tumor.