Endometrial cancer (EC) is a common malignant tumor of the female reproductive system. In recent years, its incidence has been increasing year by year, showing a younger trend. In some economically developed cities, the incidence of EC has surpassed that of cervical cancer, making it one of the most common gynecological malignant tumors. Although the overall prognosis of EC is good, with a 5-year survival rate of over 90% for early-stage patients, the application of minimally invasive techniques in its diagnosis and treatment has also brought a certain risk of tumor dissemination. With the popularization of minimally invasive techniques such as hysteroscopy and laparoscopy, how to reduce tumor spread while ensuring treatment efficacy has become an important clinical issue that urgently needs to be addressed.
This article sorts out the content of the newly released "Minimally Invasive Tumor-Free Defense Management Guidelines for the Diagnosis and Treatment of Endometrial Cancer" led by the Reproductive Health Branch of the Chinese Preventive Medicine Association in 2025, to help everyone better study and understand.
Histopathological examination is the "gold standard" for the diagnosis of EC. Currently, common clinical methods for obtaining endometrial tissue include:
Endometrial cytological sampling and low-pressure endometrial aspiration biopsy can be used as first-line screening methods for EC (Evidence level: 1B, Recommendation level: Category 2B). A systematic review and meta-analysis showed that for EC precursor lesions and malignant tumors, the sensitivity of endometrial cytological sampling brushes was 95% (95%CI 90%-98%) and the specificity was 92% (95%CI 90%-94%), which can be used for the screening of endometrial diseases.
The traditional pathological sampling method does not require uterine distension and does not increase the risk of positive abdominal cytology. For patients with typical symptoms and highly suspected EC by imaging, especially those with vaginal bleeding, diagnostic curettage is the first-line method for confirmation (Evidence level: 1A, Recommendation level: Category 2A). However, due to non-direct visualization, it may miss focal lesions in the uterine cavity and lesions in special locations. Improper operation may lead to uterine perforation and the risk of tumor dissemination. If the curetted tissue is fish-flesh-like and endometrial cancer is highly suspected, curettage should be stopped immediately.
Hysteroscopic directed biopsy has a high overall diagnostic accuracy for endometrial cancer, but there is still controversy about whether uterine distension pressure and irrigation of distension fluid lead to positive abdominal cytology and affect prognosis. Most large-sample retrospective studies and systematic reviews have shown that under standardized operation with pressure <80mmHg, hysteroscopy does not significantly increase abdominal dissemination. There are no statistically significant differences in the proportion of stage Ⅲ-Ⅳ, DFS and OS compared with the curettage group, and it is also safe for non-endometrioid carcinoma. In view of tumor heterogeneity, selective application is recommended, with strict control of uterine distension pressure and avoidance of rapid perfusion, to achieve both accurate diagnosis and tumor-free principle. In clinical practice, hysteroscopic examination with directed biopsy can be used for patients with suspected early EC, but the operation time should be shortened as much as possible, and the uterine distension pressure should be reduced, recommended to be ≤80mmHg (Evidence level: 1A, Recommendation level: Category 2A).
In the surgical treatment of endometrial cancer (EC), laparoscopy and laparotomy are the two main surgical approaches. Laparoscopic surgery includes conventional laparoscopy, single-port laparoscopy, and robot-assisted surgery. Studies have shown that there are no significant differences in survival time and recurrence rate between different surgical methods, but minimally invasive surgery has a lower complication rate compared with laparotomy, especially similar long-term survival rates. In addition, vaginal natural orifice transluminal endoscopic surgery (vNOTES), as a new minimally invasive surgical method, has shown good safety and feasibility. Especially in sentinel lymph node detection, it is equivalent to traditional laparoscopic surgery, and helps to shorten the length of hospital stay and reduce postoperative complications, especially in obese patients or those with multiple comorbidities. However, this method has high technical requirements for surgeons, and more large-scale studies are needed to verify its clinical effect.
This guideline emphasizes that in the process of selecting clinical surgical approaches, the tumor-free defense principle should be fully followed, and blind pursuit of the application of minimally invasive techniques should be avoided. The most suitable surgical approach for the patient should be determined based on comprehensive consideration of gynecological examination results, patient's comorbidities, body mass index, presence of contraindications and other factors, combined with the surgeon's experience. The following recommendations are given:
For EC patients with tumors confined to the uterus without special circumstances, minimally invasive surgery is recommended as the surgical approach (Evidence level: 1A, Recommendation level: Category 2A). Laparoscopic surgery is not recommended for patients with severe cardio-cerebrovascular diseases, pulmonary insufficiency, etc., who cannot tolerate pneumoperitoneum or special body positions. Laparoscopic surgery is not recommended for patients with abdominal hernia or diaphragmatic hernia, diffuse peritonitis with intestinal obstruction, severe pelvic and abdominal adhesions, etc., where puncture risk is high or pneumoperitoneum pressure cannot be tolerated.
For obese patients with multiple comorbidities, BMI measurement is recommended. For surgeons skilled in minimally invasive surgery, V-NOTES can be selected. At the same time, robotic surgery is recommended as the preferred surgical approach for obese patients (BMI≥30) (Evidence level: 1B, Recommendation level: Category 2B).
Laparoscopic surgery is not recommended for EC patients with large uterus (volume ≥12 gestational weeks, weight 280g) or poor vaginal conditions, or experienced surgeons may consider removing the specimen through the vagina after bagging (Evidence level: 1B, Recommendation level: Category 2B).
Tumor seeding at laparoscopic port sites (port site metastasis, PSM) must be taken seriously enough. The occurrence of PSM is related to factors such as port site contamination, tumor cell atomization, chimney effect, CO2 pneumoperitoneum effect, and immune response. To reduce the risk of PSM, the following measures should be taken: use an appropriate size trocar to reduce the gap between the trocar and the abdominal wall, fix the trocar to reduce repeated entry and exit; place the specimen into a retrieval bag as soon as possible after removal; clear abdominal fluid and rinse before removing the trocar, and place a drainage tube if necessary; remove the trocar under pneumoperitoneum-free state; thoroughly rinse the abdominal wall and close each layer of the abdominal wall layer by layer before closing the port site (Evidence level: 1B, Recommendation level: Category 2B).
The use of uterine manipulators is not recommended (Evidence level: 1B, Recommendation level: Category 2B).
In endometrial cancer (EC) surgery, early clamping of bilateral fallopian tubes can block the dissemination of tumor cells to the pelvic and abdominal cavities through the fallopian tubes. Secondly, high ligation of ovarian arteries and veins helps to improve prognosis; common methods include vascular clips, sutures or electrocoagulation. Lymph node resection is of great significance in EC staging and prognosis evaluation. Lymph node resection may not be performed in low-risk patients, while systematic resection is required in high-risk patients. Sentinel lymph node mapping is recommended by domestic and foreign guidelines for cases with low risk of lymph node metastasis confined to the uterus. It is recommended to resect sentinel lymph nodes first, and then resect the uterus (Evidence level: 1B, Recommendation level: Category 2B). Para-aortic lymph node metastasis mostly occurs above the inferior mesenteric artery, so it is recommended to resect up to the renal vein level in high-risk patients, especially focusing on the left para-aortic lymph nodes. The surgical operation should follow a systematic sequence, starting from the pelvic cavity, from lateral to medial, from far to near, and gradually expanding to the para-aortic region. Ensure en bloc resection and timely bagging, and combine neoadjuvant therapy if necessary, to minimize the risk of dissemination and improve surgical safety (Evidence level: 1A, Recommendation level: Category 2A).
Before the end of the operation, irrigate the pelvic cavity with a large amount (not less than 1000mL) of distilled water or normal saline (Evidence level: 1B, Recommendation level: Category 2B).
Except for hereditary EC and BRCA gene mutation, ovaries can be preserved in early-stage low-risk EC patients under 45 years old (histological type: endometrioid carcinoma G1/G2, superficial myometrial invasion, no lymphovascular space involvement, no cervical stromal or extrauterine involvement) after careful evaluation (Evidence level: 1A, Recommendation level: Category 2A).
The incidence of endometrial cancer (EC) is increasing and tends to be younger, leading to an increase in the demand for fertility-preserving treatment. Studies have shown that high-efficiency progestin combined with hysteroscopic lesion resection can significantly improve the complete remission rate (>90%) and pregnancy rate (34%~47.8%), and reduce the recurrence rate. Compared with curettage, hysteroscopy has the advantages of direct visualization evaluation and precise resection, which helps to preserve normal endometrium and improve fertility outcomes. However, there are still risks of tumor dissemination and surgical complications, which need to be strictly prevented and controlled during operation. For hysteroscopic operations, the guideline gives the following recommendations:
If progestin combined with surgical resection of lesions is needed during fertility-preserving treatment of EC, hysteroscopic surgery is preferred. During the operation, low uterine distension pressure should be maintained, and the pressure is preferably 70～80mmHg (Evidence level: 1A, Recommendation level: Category 2A).
For hysteroscopic surgery performed in fertility-preserving treatment of EC, once perforation occurs, tumor cells will disseminate into the abdominal cavity, which should be avoided as much as possible. Attention should be paid to protecting the normal endometrium during hysteroscopic surgery (Evidence level: 1A, Recommendation level: Category 2A).
The operation time should be shortened as much as possible if conditions permit (Evidence level: 1B, Recommendation level: Category 2B).
During the follow-up period, gynecological ultrasound and endometrial pathological examination should be performed every 6 months. After complete remission of the disease, endometrial aspiration biopsy is preferred for follow-up. If pathology suggests abnormalities or ultrasound indicates endometrial space-occupying lesions, hysteroscopic examination is recommended (Evidence level: 1B, Recommendation level: Category 2B).
Endometrial cancer is a common gynecological malignant tumor, and surgical treatment remains crucial in its diagnosis and treatment. Although minimally invasive techniques such as laparoscopy and hysteroscopy have significant advantages, violations of the tumor-free principle often occur in practical operations, which seriously threaten patient safety. Therefore, strictly following the tumor-free principle for minimally invasive surgery is not only an inheritance of the tumor-free principle, but also an important guarantee in the era of minimally invasive surgery, with great clinical significance.
