Successful Fertility Preservation in a Case of Low-Grade Endometrial Stromal Sarcoma: A Multidisciplinary Approach Through the Oncofertility Network

Abstract

Low-grade endometrial stromal sarcoma (LGESS) is a rare disease, accounting for less than 1% of all uterine malignancies. Standard treatment is total hysterectomy and bilateral tubal oophorectomy, although fertility preservation may be desirable because of the young age of onset. We document a case of fertility preservation in a 27-year-old nulligravida diagnosed with LGESS, which not only enabled the successful birth of two live infants but also underscores the efficacy of a multidisciplinary approach to patient treatment through the Hyogo Oncofertility Network (HOF-net). The patient underwent laparoscopic removal of a lesion initially suspected to be either a uterine myoma or an adnexal tumor. Through the HOF-net, a pioneering collaboration among patients, oncologists, and fertility specialists, she was connected to our department with the aim of achieving pregnancy in the future, even amidst her cancer diagnosis. Following the surgery, and during a medically advised period of contraception, assisted reproductive technology with the double stimulation (DuoStim) method was utilized to cryopreserve six embryos, followed by high-dose progestin therapy to mitigate the risk of cancer recurrence. Once the contraceptive mandate had been concluded, the implantation of the first thawed embryo during a hormone replacement cycle led to a viable pregnancy and the subsequent birth of a healthy child by cesarean section. Similarly, during the contraceptive period, after undergoing high-dose progestin therapy, a second thawed embryo transfer was performed, resulting in a successful pregnancy and the birth of a second child. Subsequently, she underwent a total hysterectomy and bilateral salpingectomy with preservation of both ovaries at another hospital 39 months after the initial surgery. No recurrence or residual disease was observed. The necessity for comprehensive informed consent was underscored by the potential for LGESS recurrence. Furthermore, the efficient coordination facilitated by the HOF-net enabled swift access to assisted reproductive services, aligning with the patient's primary healthcare plan. This case highlights the critical role of early engagement with assisted reproductive technologies and a multidisciplinary treatment strategy in facilitating successful outcomes for patients with LGESS, demonstrating the feasibility of fertility preservation in managing this condition.

Keywords: fertility preservation; frozen-thawed embryo transfer; lgess; medroxyprogesterone acetate; progesterone receptor.

Figure 1. Contrast-enhanced MR images

(A) Horizontal section T2. (B) Horizontal section T1. The arrow highlights an area with relatively weak contrast enhancement within the mass. This region exhibits a mildly high signal intensity on T2WI and a mildly low signal intensity on T1WI, suggesting it as the probable location of the malignant component. T2WI: T2-weighted imaging; T1WI: T1-weighted imaging

Figure 2. Laparoscopic surgery findings

(A) Pre-enucleation imaging: A tumor, measuring approximately 10 cm in diameter, is located on the posterior wall of the uterine fundus. (B) Post-enucleation imaging: This image demonstrates the postoperative state following tumor enucleation. The tumor was successfully extracted through a small transverse incision in the lower abdomen, utilizing an enucleation bag for containment during laparoscopy. Although there was a partial leakage of the tumor contents during the procedure, there was no evidence of extensive dissemination or seeding of tumor cells.

Figure 3. Microscopic and immunohistochemical analysis of the tissue obtained during the initial surgery

(A) H&E staining. (B) ER. (C) PgR. (D) CD10. (E) αSMA. Immunohistochemistry showed ER (+), PgR (+), CD10 (+), αSMA (+), CD34 (-), h-caldesmon (-), and desmin (-). The image of the bundle-like proliferation of oval to short spindle-shaped cells is seen. There are small intervening vessels between cells. Vitrification and cystic voids were partially observed in the interstitium, with areas showing a tendency to invade the muscle layer. The number of fission images was 0-1/10 HPFs, and there were no coagulation necrosis images or lymphatic infiltrates.