Risk factors analysis
In univariate analysis, increase of age, large palpable mass, bilateral synchronous forms at diagnosis and perioperative rupture had a statistical impact on the risk of second tumor events (Table 1, Fig. 1B and C). In the multivariate analysis, the same variables except age remained prognostic (Table 1). Neither the type of surgical approach (laparoscopy and laparotomy) nor the type of tumor resection (TO and OSS) influenced the risk of recurrence (Table 1). In the subgroup that benefited from OSS, the second event was not influenced by the initial surgical approach. Perioperative rupture was considered a risk factor for a second event, with a 2-year EFS of 85.0% [95% CI, 60.4 – 94.9] vs. 96.0% [95% CI, 92.3 – 98.0] (Fig. 1B). Twenty-four percent of patients with second events experienced a perioperative tumor rupture during an OSS procedure (Table 3). The second event was, however, on the contralateral ovary in all cases except two, where recurrence was bilateral or with JCGT in the ipsilateral ovary. Perioperative rupture during OSS was thus not associated with a second event in the ipsilateral ovary (p=0.41).