Successful ovarian tissue cryopreservation with transvaginal natural orifice transluminal endoscopic surgery: A case report

Abstract

Chemotherapy and radiation therapy can cause gonadal dysfunction in women of reproductive age. Ovarian tissue cryopreservation is performed to restore fertility by allowing transplantation of the patient’s frozen-thawed ovarian tissue or through future in vitro maturation and in vitro fertilization of frozen-thawed oocytes. Herein, we describe our initial experience with vaginal natural orifice transluminal endoscopic surgery for ovarian tissue preservation in a young woman with malignant tumor. A 23-year-old woman with anaplastic lymphoma kinase-positive malignant lymphoma was scheduled for hematopoietic stem cell transplantation after experiencing relapse following R-cyclophosphamide, doxorubicin, vincristine, and prednisolone therapy. Ovarian tissue cryopreservation was selected as only MII2 oocytes were collected. Vaginal natural orifice transluminal endoscopic surgery was performed to excise the left ovary. Ovarian tissues were frozen using the vitrification method. The operative time was 37 min, and blood loss was minimal. Pathological examination revealed no metastatic findings of malignant lymphoma and no thermal damage to the ovarian tissue due to bipolar disorder. The patient was discharged on the first day postoperatively, and her postoperative course was uneventful. The vaginal natural orifice transluminal endoscopic surgery technique can provide a safe and effective alternative to laparoscopy or laparotomy for the cryopreservation of ovarian tissue in young patients with cancer. We believe this method has potential application in sexually mature female cancer survivors.

Plain language summary

Ovarian tissue cryopreservation with vaginal natural orifice transluminal endoscopic surgery

Chemotherapy and radiotherapy can affect a woman’s ability to have children by reducing ovarian function. This can make it hard to conceive even with fertility treatments. Freezing healthy ovaries before these treatments can help restore fertility. This can be done by freezing and later transplanting ovarian tissue or by fertilizing frozen eggs in a lab. Traditional surgery to remove ovaries can cause cosmetic issues and pain. But now, a new method called vaginal spontaneous opening transperitoneal endoscopic surgery is becoming more common. This surgery is less invasive, quicker, and causes less bleeding. We recently used this method to preserve ovarian tissue in young women with cancer. The surgery was successful with minimal complications. This new approach could offer a safer option for preserving fertility in female cancer survivors.

Introduction

Gonadotoxic systemic chemotherapy and pelvic radiation therapy compromise ovarian function in women of reproductive age, causing endocrine dysfunction and depletion of the ovarian reserve, leading to permanent infertility. Therefore, it is necessary to provide fertility preservation methods to such patients prior to treatment. There are currently three fertility preservation techniques that can be applied in such patients: fertilized oocyte cryopreservation, unfertilized oocyte cryopreservation, and ovarian tissue cryopreservation (OTC). The cryopreservation of fertilized oocytes requires sperm sources. On the contrary, the cryopreservation of unfertilized oocytes requires many oocytes because the low probability of fertilization after thawing. Therefore, if many oocytes cannot be retrieved at one time, we need to retrieve our oocytes many times. If chemotherapy or pelvic radiation therapy needs to be started immediately, these two options are not indicated because of the time required. In such cases, OTC, an invasive technique, is chosen.

In recent years, remarkable progress has been made in endoscopic surgical techniques, including the development of natural orifice transluminal endoscopic surgery (NOTES). Transvaginal natural orifice transluminal endoscopic surgery (vNOTES) has been increasingly indicated since the first vNOTES cholecystectomy was reported in 2007. ¹ This technique does not require an incision in the abdominal wall and can be performed cosmetically with minimal invasion for a variety of gynecologic procedures.

In the case reported here, we performed unfertilized oocyte freezing prior to bone marrow stem cell transplantation in a woman of reproductive age with a partner. However, this procedure was unsuccessful, and we subsequently opted for OTC. This is the first report of successful harvesting of intact ovarian tissue using vNOTES. This case report was written following the CARE guidelines. ²

Case presentation

Patient information

The present patient was a 23-year-old woman with nulliparity and a regular 28-day menstrual cycle who was diagnosed with anaplastic lymphoma kinase-positive anaplastic large cell lymphoma. After diagnosis, she underwent six courses of cyclophosphamide, doxorubicin, vincristine, and prednisolone (CHOP) therapy and had been under observation since then. A total of 4500 mg/m² of cyclophosphamide, gonadotoxic chemotherapy, was administered, but her menstruation after administration remained a regular cycle. She had not been offered fertility preservation treatment prior to this treatment. Three years later, the patient presented with recurrence in the right buttock. After tumor resection, the patient was treated with 40 Gy adjuvant radiotherapy administered in 20 fractions of 2 Gy, and a 12-MeV electron beam from the dorsal side. At this time point, there was no calculated effect of therapy on the reproductive organs. Two years later, the patient presented with recurrent pelvic and left inguinal lesions. Unfertilized oocytes were collected for cryopreservation prior to allogeneic hematopoietic stem cell transplantation. After three injections of recombinant follicle-stimulating hormone (FSH) 900 units, human menopausal gonadotropin 675 units, and gonadotropin-releasing hormone antagonist 0.25 mg, choriogonadotropin alfa 250 µg was administered, and 36 h later, three MII and two MI oocytes were collected and cryopreserved. Because the number of unfertilized frozen oocytes was low, the patient was referred to our hospital for subsequent OTC.

OTC

The patient’s hormone levels on fourth day of her period were 7.25 U/L FSH and 1.03 ng/mL anti-Mullerian hormone. The timeline to OTC was performed during a natural cycle. Transvaginal ultrasound revealed a right ovary with a long diameter of 50 mm, four corpora lutea, and a left ovary with a long diameter of 30 mm and one corpora lutea. It was decided to remove the left ovary since the ovarian cortex could be easily cryopreserved. Subsequently, a left oophorectomy was performed using vNOTES. Surgery was performed under general anesthesia in the lithotomy position. Based on our hospital policy, intravenous prophylaxis of 2 g of cefmetazole was administered at induction of anesthesia. Access to the peritoneal cavity was created by making a 2-cm posterior colpotomy using electrocautery and opening the peritoneum using cold scissors. After vaginal placement of the GelPoint^® Vpath (Applied Medical), carbon dioxide (CO₂) is insufflated at 10 mm Hg to maintain an adequate pneumoperitoneum. The uterine side of the left ovarian intrinsic ligament was grasped with bipolar forceps, and the ovarian side was incised with cold scissors. Bipolar coagulation was then applied to stop the bleeding. The operation was performed from the uterine side to the pelvic funnel ligament, and oophorectomy was performed. The ovary was retrieved transvaginally. The operative time was 37 min. Blood loss was less than 50 mL (Supplementary Video 1). She was discharged on the day 1 postoperatively but developed fever and cough on postoperative day 6. The SARS-CoV-2 molecular test was carried out, which was positive. This shows that our patient had symptomatic SARS-CoV-2 infection. Therefore, after home rest until 10 days symptom resolution, hematological treatment was resumed as scheduled on day 28 postoperatively.

The ovary were cryopreserved by vitrification (closed method), ³ with the medulla removed, and the cortex was stripped to a size of 10 × 10 × 1 mm and divided into a total of 20 sections (Figure 1). Biopsy of a portion of the ovary revealed numerous healthy preantral follicles and free of any potential malignant cells. Histological examination with hematoxylin and eosin staining of the portion of the fallopian mesentery closest to the ovary revealed no burns (Figure 2). During processing, we punctured of one antral follicle and cryopreserved one additional MII oocyte.

Figure 1.

(a) The ovarian tissue immediately after removal. (b) The cortex was divided into 20 sections before cryopreservation.

Figure 2.

Pathology of the resected ovarian tissue (hematoxylin and eosin staining). Primordial follicles are observed in the cortex (yellow arrows). No thermal injury can be observed at the resected margin (red arrow). Magnification, 10×. White bar is 10 µm.

Discussion

This is the first case of OTC with unilateral oophorectomy using vNOTES. This technique is minimally invasive, cosmetic, and allows for early patient discharge, with minimal impact on the treatment schedule of the underlying disease. Our experience has also shown that oophorectomy using the vNOTES technique can be performed without triggering thermal damage to the ovaries.

We used the vNOTES technique to allow OTC with a short operative time, minimal blood loss, no scarring, and short hospital stay. A prior systematic review investigating the safety of the vNOTES technique compared to conventional laparoscopic (CL) surgery found that vNOTES was significantly safer than CL surgery, with superior operative time, estimated blood loss, and length of hospital stay. ⁴ On the contrary, patients with a narrow vagina or a frozen pelvis may have difficulty accessing the peritoneal cavity. Cryopreservation of ovarian tissue is a relatively new and promising option to preserve fertility in women diagnosed with cancer. Among the fertility preservation therapies available for young female cancer patients, OTC has the advantage of preserving a large number of oocytes, can be performed on prepubertal girls, and autologous transplantation can be expected to preserve natural pregnancy and gonadal function other than fertility. In 2004, Donnez et al. ⁵ reported the first case of pregnancy and delivery from OTC and autologous transplantation; since then, more than 130 similar births have been reported. ⁶ However, given the need to minimize delays in cancer treatment, a procedure with a minimal recovery time and fewer complications is desirable. Comparing the results of CL and vNOTES techniques for benign adnexal lesions, the operative time and hospital stay were significantly shorter in the vNOTES group, and postoperative visual analog scale (VAS) pain scores were also significantly lower in the vNOTES group. ⁷ Our experience with fertility-sparing oophorectomy using the vNOTES technique suggests that this technique fulfills these requirements.

In the present case, we examined a piece of ovarian tissue after surgery, finding no evidence of thermal injury. The following three processes are necessary for fertility preservation in surgical procedures: (1) ovarian removal, (2) ovarian thinning and cryopreservation, and (3) ovarian transplantation. Ovarian damage is inevitable in all of these processes, resulting in the loss of 70%–80% of the oocytes from removal to transplantation, compared to normal ovaries.^8,9 Blood flow disturbance during ovarian tissue thawing is the most influential factor for oocyte loss; a deficiency in nutritional supply from the surrounding tissues and hypoxia are thought to last approximately 3–5 days after transplantation, and it takes approximately 10 days for blood flow to resume. ⁸ Therefore, it is necessary to devise methods to avoid damage to the ovaries as much as possible during oophorectomy. In particular, it is necessary to prevent thermal coagulation associated with hemostatic manipulation from reaching ovarian tissue. When we perform partial oophorectomy, it is necessary to grasp the large part of the ovary to be removed, and there is concern about damage to the follicle. There are also complications, such as the need to cauterize the resection surface of the remaining ovary, which may reduce residual ovarian function, and the risk of postoperative hemorrhage. We therefore perform total ovarian ablation with the aim of avoiding these risks. Removal of the ovary first with cold scissors and subsequent electrocoagulation of the resected segment can reduce damage to the ovary.^10,11 Laparoscopic surgery is also preferable to open surgery in terms of perioperative pain, length of hospital stay, and abdominal aesthetics. ¹⁰ In the present case, we performed conventional laparoscopic oophorectomy, with good results. The vNOTES technique also allowed us to remove ovarian tissue without coagulation, with cold scissors and bipolar forceps minimizing the thermal damage to the ovaries.

We performed total removal of the left ovary, which had a lower corpus luteum. In FertiPROTEKT, only a portion of the ovarian tissue is cut and removed for freezing in 97% of cases ¹² ; however, unilateral ovariectomy allows more sections to be frozen. ¹³ In the present case, the ovary was removed from the left side, where there was little luteal residue, as luteal residue can complicate freezing of the ovaries. A similar report of a case in which an ovary was removed after chemotherapy for leukemia, and the ovarian tissue was transplanted after remission, resulting in pregnancy has also been published. ¹⁴ Although cryopreservation was also performed after chemotherapy in this case, it was confirmed that numerous follicles remained in the tissue, and future pregnancy was expected.

Unfortunately, the general indications for vNOTES oophorectomy are limited. First, it is limited to mature postmenopausal female patients with sexual intercourse. Second, patients with serious hematologic diseases such as leukemia may be at a higher risk of postoperative infection. Third, there is a potential risk of recurrence upon reimplantation of ovarian tissue. Thus, the safety of vNOTES oophorectomy requires further investigation.

Conclusion

In conclusion, unilateral oophorectomy by vNOTES for fertility preservation allows early discharge with minimal impact on the treatment schedule of the primary disease and can be performed without thermal injury to the ovary, similar to conventional laparoscopic surgery.

Supplemental Material

sj-docx-1-whe-10.1177_17455057241239308 – Supplemental material for Successful ovarian tissue cryopreservation with transvaginal natural orifice transluminal endoscopic surgery: A case report

Supplemental material, sj-docx-1-whe-10.1177_17455057241239308 for Successful ovarian tissue cryopreservation with transvaginal natural orifice transluminal endoscopic surgery: A case report by Tetsuro Hanada, Akimasa Takahashi, Yuji Tanaka, Akie Takebayashi, Yoshie Matsuda, Makiko Kasahara, Shunichiro Tsuji and Takashi Murakami in Women’s Health