Laparoendoscopic single-site surgery for ovarian mature teratomas in children and adolescents: a retrospective cohort study

Introduction

Ovarian mature teratoma (OMT) is a common benign ovarian tumor. It occurs mostly in women from adolescence to menopause, especially in young women (1). OMT is usually found incidentally on imaging performed for other indications (2). Although OMT is benign, a few are associated with various complications including tumor rupture, adnexal torsion, and malignant transformation, which can cause serious harm to patients (3). The main treating method of OMT is surgical removal, performed by laparotomy or laparoscopy (4). Laparotomy has the disadvantages of large trauma, slow recovery and more complications, and has been gradually replaced by laparoscopy. Laparoscopy has the advantages of small trauma, fast recovery and good cosmetic effect, and is the preferred method for OMT.

Laparoendoscopic single-site surgery (LESS) is a new type of laparoscopic surgery, which is performed through a 2–3 cm incision in the umbilicus, and the laparoscope and instruments are inserted to complete the operation (5). Compared with the traditional open surgery, LESS has less trauma, better cosmetic effect and higher patient satisfaction, especially for young female patients with OMT. Compared with standard laparoscopic surgery, specimen removal is easier with LESS, which has an incision of 3 cm at the umbilicus. However, there is a lack of evidences for children and adolescent girls with OMT using LESS. The aim of the present study is to evaluate the safety and efficacy of LESS for the management of children and adolescents with OMT. We present this article in accordance with the STROCSS reporting checklist (available at https://gpm.amegroups.com/article/view/10.21037/gpm-25-6/rc).

Methods

Participants

Patients who underwent LESS or open surgery in West China Second Hospital, Sichuan University, from 01/01/2019 to 31/12/2023, were enrolled in this study. Inclusion criteria were as follows: (I) female patients aged 18 years or younger; (II) preoperative transabdominal or transvaginal ultrasound suggested ovarian teratoma; (III) surgical methods were trans-umbilical LESS cystectomy + Zheng’s anchor suturing technique (6), or laparotomic cystectomy; (IV) paraffin pathology confirmed OMT. Exclusion criteria was as follow: paraffin pathology confirmed ovarian immature teratoma or other ovarian tumors.

Surgical methods

Trans-umbilical LESS cystectomy + Zheng’s anchor suturing technique

(I) The patient was placed in a supine position. After satisfactory anesthesia, routine disinfection and draping were performed. A 2 cm longitudinal incision was made at the umbilicus, cutting through the skin, subcutaneous fat, fascia, and peritoneum to enter the abdominal cavity. A disposable trocar was placed in the umbilical incision, and instruments were introduced through the trocar for operation; (II) the patient was placed in a Trendelenburg position, and a comprehensive exploration of the pelvic cavity was conducted; (III) the ovarian cyst was lifted with atraumatic forceps. Along the area with fewer blood vessels, the ovarian cortex was incised in an arc shape using a monopolar hook. The incision edge was lifted, and the cyst was bluntly dissected with the assistance of curved forceps, ensuring complete enucleation of the cyst; (IV) the ovary after cyst removal was sutured and reconstructed with absorbable sutures; (V) the excised ovarian cyst was placed in a specimen retrieval bag and removed through the umbilical incision; (VI) the pelvic cavity was repeatedly irrigated with saline, and hemostasis was confirmed. Surgical instruments and materials were counted and verified before removal; (VII) the apex of the peritoneal and fascial incision was pulled with a suture and fixed with a knot. The fascia and peritoneum were closed with a continuous suture using 2-0 absorbable sutures. A 2-0 absorbable suture was introduced from the base of the fascial incision, passed through the subcutaneous tissue of the area, and exited as close to the skin as possible before suturing the opposite side, leaving it untied temporarily for traction. The subcutaneous tissues at both apices and the central fixation area were intermittently sutured. A 4-0 absorbable suture was used for a continuous intradermal suture at the upper and lower ends, with downward pressure applied during suturing to further create a slope.

Laparotomic cystectomy

(I) The patient was placed in a supine position. After satisfactory anesthesia, routine disinfection and draping were performed. A midline incision was made in the lower abdomen, sequentially cutting through the skin, fascia, rectus sheath, and peritoneum to enter the abdominal cavity; (II) a thorough exploration of the pelvic cavity was conducted; (III) the ovarian cyst was lifted, and along the area with fewer blood vessels, the ovarian cortex was incised in an arc shape using a scalpel. The incision edge was elevated, and the cyst was dissected with scissors to ensure complete enucleation; (IV) the ovary after cyst removal was reconstructed and sutured with absorbable sutures; (V) the pelvic cavity was repeatedly irrigated with saline, and hemostasis was confirmed. Surgical instruments and materials were counted and verified before removal; (VI) the abdomen was closed layer by layer.

Study design

This study was a retrospective cohort research and patients were divided into LESS cohort and open surgery cohort based on their surgical approaches. Basic information, surgical conditions and postoperative conditions were collected. Basic information included age, body mass index (BMI), history of previous abdominal surgery, menarche and symptoms. The primary outcomes of the study were the safety and efficacy of surgery. To evaluate the safety and efficacy, we collected surgical conditions, postoperative conditions and complications. Surgical conditions included tumor location and diameter, operation time and blood loss. In laparoscopic surgery, tumor size was measured visually, while in open surgery, it was measured with a ruler after cyst excision. Postoperative conditions included postoperative mortality, urination time, exhaust time, pain score and hospital stay. Urination time referred to the time from removing the catheter to the patients being able to urinate on their own; exhaust time referred to the time from the end of surgery to the patients feeling anal gas; pain score referred to the subjective score of pain by the patients within 24 hours after surgery, using the Visual Analogue Scale (VAS), 0 point for no pain, 10 points for the most intense pain. Besides, postoperative complications were collected. Patients were followed up one month and one year after surgery by phone-call, and recurrence was recorded.

Statistical analysis

Measurement data, including age, height, weight, BMI, diameter, time, score and stay, presented as mean ± standard deviation, were compared with a t-test. Count data, including previous history, symptoms, and complications, was compared with chi-square test. A two-sided P value less than 0.05 was considered significant difference. All analyses were performed with software STATA (version 17.0, Stata Corporation, USA).

Ethics approval and consent to participants

This study was approved by the ethics committee on human research at West China Second Hospital, Sichuan University (No. 2023100). The study was conducted in accordance with the Declaration of Helsinki and its subsequent amendments. The patients provided informed consent for the publication of their clinical data.

Results

We collected 178 cases and 9 cases were excluded due to paraffin pathology. The detailed data are provided in Figure 1. Among these included 169 cases, 14 cases were emergency surgeries due to adnexal torsion, 3 cases were accompanied by congenital heart disease, 1 case was accompanied by asthma, and 3 cases were accompanied by obesity. In total, 151 LESS cases and 18 open cases were included and patients’ basic characteristics are shown in Table 1. The average ages of two groups were 13.5±0.5 and 13.3±0.6 years, with no statistical difference (P=0.84). The average BMIs of two groups were 20.0±0.3 and 20.1±1.1 kg/m², with no statistical difference (P=0.93). As for menstrual history, no statistical difference was found (P=0.93). Irregular menstruation was the most common symptom in this study (16.0%, 27/169). However, we found a statistical difference in symptoms between groups (P<0.001).

Figure 1 Flow chart of inclusion and exclusion criteria for participants.

Surgical outcomes are shown in Table 2. There was no postoperative mortality. Unilateral cystectomy was performed for 154 patients and bilateral cystectomy was performed for the other 15 patients. No patients required additional ports or conversion to laparotomy to complete the planned surgery. The average size of the tumors in LESS group was 6.5±0.2 cm, and Figure 2 showed the distribution of different tumor sizes, which was relatively normal. Compared with open group, the tumors in LESS group were smaller and the difference was statistically significant (6.5±0.2 vs. 18.9±1.0 cm, P<0.001). For surgical duration, statistical difference was found between LESS group and open group (92.4±2.6 vs. 132.5±14.0 min, P<0.001). Besides, we found statistical difference for blood loss between groups (24.1±3.4 vs. 93.9±29.9 mL, P=0.02). As for postoperative complications, statistical difference was found (P<0.001). One case of wound infection in LESS group was noted. This 11-year-old patient was infected by Pseudomonas aeruginosa. Doctors changed the dressing of the incision twice a day and the patient was discharged on Day 12 after surgery with good wound healing. One case of intestinal obstruction in open group was recorded. This 12-year-old patient complained abdominal distension and pain on the Day 3 after surgery. Gastrointestinal decompression was given and abdominal CT revealed intestinal obstruction. After treatment with traditional Chinese medicine, the patient was released on Day 5 after surgery. Besides, for urinary retention, one case of LESS group and two cases of open group were recorded. Compared with open group, the postoperative conditions in LESS group were better. We found statistical differences for exhaust time (17.0±0.2 vs. 24.7±3.3 hours, P<0.001) and hospital stay (4.1±0.1 vs. 5.8±0.5 days, P<0.001) between LESS group and open group. However, statistical difference was not found for urination time (2.4±0.1 vs. 2.3±0.3 hours, P=0.68), and pain score (3.3±0.1 vs. 3.8±0.3, P=0.15). Patients were followed up in the clinic or by phone-calls, 40 out of 169 patients were lost (34 from LESS and 6 from open group). No umbilical hernia was noted but 2 cases of poor wound healing were recorded. Among the 27 patients with irregular menstruation, 21 recovered normal menstruation but 6 were lost. One patient became pregnant and delivered in the LESS group. No patients had recurrence.

Figure 2 The distribution of tumor diameter in laparoendoscopic single-site surgery group.

Discussion

This study aimed to compare the safety and efficacy of LESS and open surgery for the treatment of OMT. Our results suggested that LESS was safe and feasible in the surgical management of OMT. The results showed that LESS group had significantly less operation time, blood loss, complications, and faster recovery than the open group, indicating that LESS had better minimally invasive and fast recovery characteristics.

LESS is a novel minimally invasive technique that enters the abdominal cavity through the umbilicus and uses special instruments to perform the operation, avoiding the trauma and complications caused by multiple incisions (7). This study further confirmed the advantages of LESS in the treatment of OMT. Compared with laparotomy, LESS can reduce surgical trauma, shorten hospital stay, and improve patients’ satisfaction. Compared with traditional multi-port laparoscopy (MPL), LESS was associated with less postoperative pain and required less analgesia, leading to improved patient satisfaction (8). Besides, OMT may contain hard tumor components such as bone or cartilage, making them difficult to dissect and requiring an abdominal wall incision of about 3 cm for removal. Therefore, removal is easier with LESS, which has an incision of 3 cm at the umbilicus, than with MPL. LESS is not inferior to MPL in OMT surgery, and LESS is useful for the surgery of OMT. In our study, limited complications were recorded, demonstrating that LESS confers feasibility, convenience, and safety regarding cystectomy of MPL (9).

The appropriate surgical treatment for pediatric patients with ovarian lesions is heterogeneous, but ovarian preservation is desirable. Indeed, the right balance between adequate and appropriate tumor resection and maximal fertility preservation is the main objective in this subset of patients. Cerovac et al. found a high trend in ovarian-sparing surgery using the endoscopic approach in management of adnexal tumors (10). And Paulette et al. revealed that benign ovarian lesions in children can be treated successfully with ovarian-sparing surgery with MPL (11). In this study, all patients underwent cystectomy to preserve ovarian function as much as possible, regardless of the size of OMT, which was in keeping with the new finding (12). Except for the 6 lost patients, 21 patients with irregular menstruation all recovered normal menstruation after surgery, indicating LESS is suitable for young patients with ovarian preservation desire. We also noticed that there were fewer menstrual abnormalities in open group. We speculate that the reason may be that the large tumor has destroyed the ovary on that side, and usual endocrine function of the patient is compensated by the normal ovary on the other side; the surgery does not affect her menstruation. The menstrual abnormalities in the LESS group may be related to the tumor or the fact that the patient is in puberty and a normal menstrual cycle has not yet been established. With the removal of the tumor and the increase in age, her menstruation gradually returned to normal. Additionally, our study revealed that 102 cases were asymptomatic, suggesting that guardians should schedule regular health check-ups for their daughters to prevent potential ovarian function impairment caused by tumor growth.

We found that all gynecologists in our hospital chose laparotomy when the tumor size was larger than 15 cm, suggesting that larger tumors may lead to poor surgical field exposure, heavy instrument interference, and thus increase the difficulty of surgery and risk of switching to open surgery. The operation time and blood loss of the open group were longer and more than those of the LESS group, which may be due to: (I) the average tumor diameter of the open group was larger than that of the LESS group, requiring more time to remove; (II) the abdominal incision of the open group was longer, and the time spent on opening and closing the abdomen was longer than that of the LESS group closing the umbilical incision. Therefore, the tumor size in the treatment of OMT with LESS may be related to its selection criteria, that is, it is only suitable for smaller tumors. Open surgery can be applied to larger or complex tumors. However, this finding was just a conclusion of retrospective reports, but there was no relevant literature to support this finding. We suggest that further research is needed to confirm this hypothesis.

This study also had some limitations that need to be improved in future research. Firstly, this study was a retrospective design and the low number of patients in open surgery, so the strength of the evidence may not be high. Secondly, patients were followed up for a short time, which made it hard to understand the impact of surgery on patients’ long-term fertility and recurrence. Thirdly, in terms of the choice of surgical approach, our evidence showed that the open approach was more suitable for larger tumors but this study did not calculate the threshold. Therefore, future studies should extend the follow-up time, determine the threshold of tumor size, and evaluate the long-term effects of surgery, especially its impacts on menstruation and pregnancy.

Conclusions

In summary, this study provides evidence and support for the application of LESS in gynecology and shows that LESS is a safe and effective method for female children and adolescents with OMT. A tumor diameter <15 cm may serve as one of the factors favoring LESS, but the final surgical approach should be determined through comprehensive consideration of tumor characteristics, the patient’s general condition, and fertility requirements.

Acknowledgments

None.

Footnote

Reporting Checklist: The authors have completed the STROCSS reporting checklist. Available at https://gpm.amegroups.com/article/view/10.21037/gpm-25-6/rc

Data Sharing Statement: Available at https://gpm.amegroups.com/article/view/10.21037/gpm-25-6/dss

Peer Review File: Available at https://gpm.amegroups.com/article/view/10.21037/gpm-25-6/prf

Funding: This work was supported by Natural Science Foundation of Sichuan Province, China (No. 2025ZNSFSC0541), National Natural Science Foundation for Young Scientists of Sichuan province, Sichuan Science and Technology Program (No. 2025ZNSFSC1670), China Health Promotion Foundation (No. 23H1547), China Health & Medical Development Foundation (No. 24H114), and Sichuan Medical Science and Technology Innovation Research Institute Fund (No. YCH-KY-YCZD2024-279).

Conflicts of Interest: All authors have completed the ICMJE uniform disclosure form (available at https://gpm.amegroups.com/article/view/10.21037/gpm-25-6/coif). J.Z. serves as an unpaid editorial board member of Gynecology and Pelvic Medicine from January 2025 to December 2025. The other authors have no conflicts of interest to declare.

Ethical Statement: The authors are accountable for all aspects of the work in ensuring that questions related to the accuracy or integrity of any part of the work are appropriately investigated and resolved. The study was conducted in accordance with the Declaration of Helsinki and its subsequent amendments. This study was approved by the ethics committee on human research at West China Second Hospital, Sichuan University (No. 2023100). The patients provided informed consent for the publication of their clinical data.

Open Access Statement: This is an Open Access article distributed in accordance with the Creative Commons Attribution-NonCommercial-NoDerivs 4.0 International License (CC BY-NC-ND 4.0), which permits the non-commercial replication and distribution of the article with the strict proviso that no changes or edits are made and the original work is properly cited (including links to both the formal publication through the relevant DOI and the license). See: https://creativecommons.org/licenses/by-nc-nd/4.0/.

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