Preoperative differentiation between tumor-related ovarian torsion and rupture of ovarian cyst preoperatively diagnosed as benign: a retrospective study.

INTRODUCTION: Patients with ovarian cyst sometimes present with acute abdomen caused by ovarian torsion or rupture, which are difficult to differentiate preoperatively. The purpose of this study was to determine preoperative features of patients with ovarian cyst that could be used in differentiation.

MATERIAL AND METHODS: Among 1723 patients with a preoperative diagnosis of benign ovarian cyst who underwent surgery between 1995 and 2010, 77 patients with ovarian torsion and 21 patients with ruptured ovarian cyst were retrospectively evaluated. The mean preoperative age, serum C-reactive protein (CRP) level, white blood cell count, body temperature, cyst size, and rate of acute abdomen were compared between the two groups, and postoperative pathological data were also collected.

RESULTS: There were significant differences between the torsion and rupture groups in the mean preoperative CRP levels (0.9 mg/dL vs 6.6 mg/dL, respectively; P<0.01) and in the mean ovarian cyst sizes (9.7 cm vs 6.7 cm, respectively; P=0.04).

CONCLUSION:   In this study, the patients with ruptured ovarian cyst had elevated CRP levels. Another study has demonstrated that there was risk for necrosis in torsion patients with elevated CRP levels who presented more than 10h after the onset of acute abdomen. Therefore, preoperative differential diagnosis between ovarian torsion and rupture may be possible by combining the findings from preoperative imaging, data on the time from onset of acute abdomen, and CRP values.