Shiyu Chen

Unilateral hyperreactio luteinalis of the ovary during pregnancy mimics ovarian malignancy: A case report

Rationale: Hyperreactio luteinalis (HL) involving a unilateral ovary is extremely rare, and the clinical presentation of HL can mimic that of ovarian malignancy, resulting in potential misdiagnosis and unnecessary surgical interventions. Patient concerns: A 34-year-old female (gravida 6, para 1), pregnant for 6 weeks according to her menstrual records, presented with nausea and abdominal distension. Diagnoses: Ultrasonography revealed unilateral ovarian enlargement with multilocular cysts and ascites. Cancer antigen 125 (CA125) was elevated at 337.6 U/mL, raising suspicion of ovarian malignancy. Interventions: Surgery was performed due to the initial impression of malignancy. Intraoperative frozen section examination revealed multiple luteinized cysts, confirming HL. Outcomes: The final diagnosis of HL was established, and unnecessary radical surgical procedures were avoided. The patient has followed up for >3 years, and there are no abnormalities in her serum CA125 and gynecological ultrasound results. Lessons: HL can mimic as ovarian malignancy, when encountering pregnant women with ovarian enlargement, elevated CA125 levels, and ascites, HL should be considered as a potential differential diagnosis. This awareness is crucial for accurate diagnosis and appropriate management, helping to avoid unnecessary surgical interventions.