Borderline ovarian tumours: balancing risks of recurrence over decades

摘要

Borderline ovarian tumours account for 10–15% of epithelial tumours. Women affected are on average 10 years younger than those with invasive ovarian epithelial tumours (Morice et al. Lancet Oncol 2012;13:103–15) and many will have fertility as a major concern. Often women are unexpectedly diagnosed after conservative surgery, following either cystectomy or unilateral oophorectomy. Frozen section can be useful for intra-operative management (Ratnavelu et al. Cochrane Database Syst Rev 2016;(3):CD010360), informing a conservative surgical approach of a suspicious mass. However, what should we do about staging, if the diagnosis was unsuspected, and about management of remaining ovarian tissue, in the short and longer term? In this issue Ouldamer et al. analysed outcomes of 360 women with borderline tumours and devised a risk scoring system for recurrence. This may help patients when considering whether to have further surgery or fertility-conservation. However, it has a few major limitations. The results have not been externally validated in a separate patient population, posing a significant challenge to the validity and applicability of the conclusions. Another limitation is the median follow up of 60 months. Borderline tumours can recur decades after the initial diagnosis, so recurrence risks in this study are likely to be an underestimate of the longer term risks. In addition, hazard ratios of several variables (age, serous histology, age), incorporated into the multivariate analysis, have wide confidence intervals that cross 1. This implies that factors may not be independently significant, perhaps due to sample size, length of follow up and small number of recurrences. Previous studies have examined risks of recurrence and survival after a diagnosis of a borderline ovarian tumour. A nationwide study from Denmark of 1042 women, confirmed after central review of histology, diagnosed between 1978 and 2002, found that extra-ovarian implants, especially invasive implants, were associated with an increase in recurrence and reduction in overall survival (Hannibal et al. Gynecol Oncol 2014;134:267–73). The ROBOTS study of 950 German women, diagnosed between 1998 and 2008 (Trilsch et al. Ann Oncol 2014;25:1320-7), found that extra-ovarian implants, incomplete staging surgery, fertility-preservation and residual macroscopic tumour were associated with relapse. As yet there are no data for overall survival. However, of the 74 women who relapsed, 30% had invasive disease (2.3% of all women), although this was less frequent in women <40 years of age at diagnosis compared with those >40 (12.0 versus 66.7%, P < 0.001). The scoring system in this issue (Ouldamer et al. BJOG 2017;124: 935–42) should be tested in these large independent patient cohorts. Further information about histological and molecular risk factors are to be expected from ROBOTS and other on-going studies, although, as studies need prolonged follow-up periods, this is likely to be sometime hence. In the meantime, our recommendations should acknowledge the limitations in data that inform us. Current data suggest that completion surgery should be offered, especially in women who have finished their families. Younger women appear to have lower risk of malignant transformation in conserved ovaries, although the risk of recurrent borderline tumours in conserved ovaries is high, especially after cystectomy. None declared. Completed disclosure of interests form available to view online as supporting Information. Please note: The publisher is not responsible for the content or functionality of any supporting information supplied by the authors. Any queries (other than missing content) should be directed to the corresponding author for the article.