Identification of a DICER1 mutation in a preeclamptic patient with ruptured ovarian Sertoli-Leydig cell tumor and renal allograft failure under hemodialysis: a case report.

BACKGROUND: Patients with renal allograft failure undergoing hemodialysis may be associated with an increased risk of preeclampsia. Preeclampsia can present with systemic manifestations, including organ bleeding. In this case, a suspected placental abruption was eventually confirmed to be caused by the rupture of an ovarian Sertoli–Leydig cell tumor (SLCT). A DICER1 mutation was subsequently identified in the patient. CASE PRESENTATION: A 30-year-old primigravid woman with a history of thyroidectomy and renal allograft failure on maintenance hemodialysis presented at 29 weeks of gestation with a blood pressure of 180/110 mmHg and sudden onset of abdominal pain. She was diagnosed with preeclampsia. Due to suspected placental abruption and acute fetal distress, an emergency cesarean section was performed, resulting in the delivery of a healthy baby girl. During the operation, approximately 600 g of intraperitoneal blood clots were found, secondary to a ruptured ovarian cyst. Histopathological examination revealed a moderately to poorly differentiated ovarian SLCT. Targeted next-generation sequencing identified a new DICER1 variant (c.3175 dup: p.Tyr1059LeufsTer32 in exon 20 of chr14:95571502) in peripheral blood samples. The frameshift variant induces a premature termination classified as likely pathogenic based on ACMG criteria. Analysis of the family pedigree reveals a clustering of earlier-onset renal disease. During the 22-month follow-up period, following the decline of adjuvant chemotherapy, the patient experienced a second unintended pregnancy that required medical termination. No evidence of SLCT recurrence was observed. CONCLUSIONS: This case report presents a unique pregnant patient with a history of thyroidectomy and living-renal allograft failure requiring hemodialysis, who developed preeclampsia and a ruptured ovarian SLCT. To our knowledge, this appears to be the first combination of a DICER1-mutation-associated ovarian SLCT in a pregnant patient with transplant failure. This highlights the pivotal need for systematic preconception counseling and effective contraceptive education in this population. A well-coordinated multidisciplinary team approach was imperative to secure optimal maternal and fetal outcomes.