Recurrent Giant Ovarian Cysts in Biological Sisters: 2 Case Reports and Literature Review—Giant Ovarian Cysts in 2 Sisters

<b>Background:</b> Ovarian follicular cysts often resolve spontaneously, with giant forms being a rarity. Cases of giant ovarian follicular cysts in biological sisters without clear familial predisposition are even exceptional. <b>Cases Presentation:</b> Two biological sisters presented to our hospital with large pelvic masses in the setting of a clinical and biological hyperandrogenism. After surgical removal, pathology confirmed the diagnosis of ovarian follicular cysts. Recurrence was detected shortly after surgery, with both sisters displaying similar clinical courses. Chromosomal screening showed no abnormalities. Hormonal analysis revealed elevated anti-Müllerian hormone (AMH), prolactin (PRL), and testosterone, alongside low FSH and LH levels. Family exome sequencing also showed no significant findings. After treatment with bromocriptine and short-acting contraceptive pills, the recurrent ovarian cysts resolved spontaneously, and hormonal levels returned to normal ranges. <b>Conclusions:</b> In women of childbearing age, it is important to conduct thorough endocrine evaluations and genetic screenings following the occurrence of large ovarian follicular cysts. Once endocrine levels are balanced, follicular cysts may decrease in size substantially, which helps to avoid unnecessary ovarian surgery.