To what extent should para-aortic lymphadenectomy be carried out for surgically staged endometrial cancer?

Paraaortic lymph node metastasis in endometrial cancer patients: a comprehensive analysis of rates, survival outcomes, and risk factors through systematic review and meta-analysis

Introduction

This study aims to explore the incidence of different metastatic patterns in paraaortic lymph nodes and their corresponding survival outcomes in patients with endometrial cancer, as well as to identify the associated risk factors of such metastasis.

Material and methods

PubMed, Embase, Cochrane Central Register of Controlled Trials, International Clinical Trials Registry Platform, and Clinical Trials.gov were searched from inception to February 10, 2024.The analysis was conducted using R version 4.2.3.

Results

A total of 47 studies involving 33,425 endometrial cancer patients were analyzed. Meta-analysis results revealed that the rate of isolated paraaortic lymph node metastasis, where pelvic lymph nodes were negative but paraaortic lymph nodes were positive (PLN-PAN+), was found to be 2.58% (95% CI 0.0195-0.0329). The rates for PLN+PAN- and PLN+PAN+ were notably higher at 8.54% (95% CI 0.0642-0.1092) and 8.37% (95% CI 0.0613-0.1090), respectively. For clinical stage I EC, the occurrence rate was 5.92% for PLN+PAN- (95% CI 0.0258-0.1032), 1.00% for PLN-PAN+ (95% CI 0.0081-0.0120), and 2.99% for PLN+PAN+ (95% CI 0.0188-0.0431). The survival outcomes indicate a decreasing trend from the PLN-PAN+ and PLN+PAN- groups to the PLN+PAN+ group. Additionally, the survival outcomes of patients with isolated paraaortic lymph node metastasis appear to be comparable to, or not inferior to, those of the PLN+PAN- group. The analysis indicated that pelvic lymph node metastasis (OR 16.72, 95% CI 10.03-27.86), myometrial invasion ≥50% (OR 5.18, 95% CI 3.09-8.69), lymph-vascular space invasion (LVSI) (OR 3.46, 95% CI 2.49-4.81), cervical invasion (OR 4.00, 95% CI 2.09-7.66), and non-endometrioid cancer (OR 2.39, 95% CI 1.17-4.86) were risk factors for paraaortic lymph node metastasis.

Conclusions

Isolated paraaortic lymph node metastasis, though relatively rare, can still occur even in clinical stage I endometrial cancer. The survival outcomes of patients with isolated paraaortic lymph node metastasis appear to be comparable to, or not inferior to, those of the PLN+PAN- group. Even in patients with negative pelvic lymph nodes, careful consideration should be given to the possibility of paraaortic lymph node metastasis, especially in those with high-risk factors.

Systematic review registration

https://www.crd.york.ac.uk/prospero/, identifier CRD42024503959.

Implications of Isolated Para-Aortic Lymph Node Metastasis in Endometrial Cancer: A Large-Scale, Multicenter, and Retrospective Study

Objective: To systematically evaluate lymph node metastasis (LNM) patterns in patients with endometrial cancer (EC) who underwent complete surgical staging, which included systematic pelvic and para-aortic lymphadenectomy.

Methods: Four thousand and one patients who underwent complete surgical staging including systematic pelvic and para-aortic lymphadenectomy for EC were enrolled from 30 centers in China from 2001 to 2019. We systematically displayed the clinical and prognostic characteristics of patients with various LNM patterns, especially the PLN-PAN+ [para-aortic lymph node (PAN) metastasis without pelvic lymph node (PLN) metastasis]. The efficacy of PAN+ (para-aortic lymph node metastasis) prediction with clinical and pathological features was evaluated.

Results: Overall, 431 of the 4,001 patients (10.8%) showed definite LNM according to pathological diagnosis. The PAN+ showed the highest frequency (6.6%) among all metastatic sites. One hundred fourteen cases (26.5%) were PLN-PAN+ (PAN metastasis without PLN metastasis), 167 cases (38.7%) showed PLN+PAN-(PLN metastasis without PAN metastasis), and 150 cases (34.8%) showed metastasis to both regions (PLN+PAN+). There was also 1.9% (51/2,660) of low-risk patients who had PLN-PAN+. There are no statistical differences in relapse-free survival (RFS) and disease-specific survival (DSS) among PLN+PAN-, PLN-PAN+, and PLN+PAN+. The sensitivity of gross PLNs, gross PANs, and lymphovascular space involvement (LVSI) to predict PAN+ was 53.8 [95% confidence interval (CI): 47.6–59.9], 74.2 95% CI: 65.6–81.4), and 45.8% (95% CI: 38.7–53.2), respectively.

Conclusion: Over one-fourth of EC patients with LMN metastases were PLN-PAN+. PLN-PAN+ shares approximate survival outcomes (RFS and DSS) with other LNM patterns. No effective clinical methods were achieved for predicting PAN+. Thus, PLN-PAN+ is a non-negligible LNM pattern that cannot be underestimated in EC, even in low-risk patients.

Systemic Laparoscopic Para-Aortic Lymphadenectomy to the Left Renal Vein

Background

No large-scale clinical study has been done to show the standard surgical boundary and efficacy of laparoscopic para-aortic lymphadenectomy (LPAL).

Objectives

Therfore, this study aimed to evaluate the feasibility, efficacy, and standard surgical boundary of LPAL performed up to the left renal vein level in gynecological malignancies.

Methods

Medical records of 333 patients were retrospectively reviewed. All cases had gynecologic malignancies and had an operation including LPAL by a single surgical team between November 2003 and May 2018.

Results

Three hundred twenty-six patients underwent LPAL as part of their staging, restaging, or debulking surgery. Seven patients with isolated para-aortic lymph node recurrence underwent a repeat LPAL. The median age and body mass index were 54 years (range, 28-81 years) and 26.0 kg/m² (range, 20.3-37.2 kg/m²), respectively. The median operating time was 60 minutes (range, 24-135 minutes), and the median number of harvested para-aortic lymph nodes was 12 (range, 6-49). There were 11 cases of complications: 5 of major vessel injuries (3 inferior vena cava, 1 aorta, and 1 common iliac vein), 2 lymphocysts, 2 cases of chylous ascites, a cisterna chyli rupture, and 1 case of ureteric injury. There were 2 conversions to laparotomy: 1 left common iliac vein laceration that needed to be repaired and removal of an enlarged para-aortic lymph node completely.

Conclusion

It is feasible and efficient to perform LPAL to the left renal vein level for women with gynecologic malignancies by well-trained gynecologic oncology surgeons according to our suggested standard surgical boundary.

The Basics of Sentinel Lymph Node Biopsy: Anatomical and Pathophysiological Considerations and Clinical Aspects

Sentinel lymph node (SLN) is the first node to receive the drainage directly from a tumor. Detection and pathological examination of the SLN is an important oncological procedure that minimizes morbidity related to extensive nodal dissection. SLN biopsy was first reported in 1960 but took approximately 40 years to come into general practice following reports of good outcomes in patients with melanoma. After many years of observation and research on its use in various malignancies SLN biopsy has become the standard surgical treatment in patients with malignant melanoma, breast, vulvar, and cervical cancers. Along with the introduction of new technologies, such as the fluorescent dyes indocyanine green (ICG) and near-infrared fluorescence (NIR), and pathologic ultrastaging, SLN detection rate has increased and false-negative rate has decreased. This literature review aimed to present an overview of the basic concepts and clinical aspects of SLN biopsy in the light of the current research.

Robotic-Assisted Infrarenal Para-aortic Lymphadenectomy in Gynecological Cancers: Technique and Surgical Outcomes

OBJECTIVE

Mini-invasive surgery has essentially replaced open laparotomy in surgery for endometrial and cervical carcinoma. Of the procedures needed for a complete staging, especially para-aortic lymphadenectomy (PALND) is challenging to perform. The present study was undertaken to investigate the technical and surgical outcomes of robotic-assisted PALND for gynecological cancers in the setting of a tertiary university hospital in Finland.

METHODS

This was a retrospective chart review of 283 robotic-assisted para-aortic lymphadenectomies using the single-docking transperitoneal technique performed at the Department of Obstetrics and Gynecology of Tampere University Hospital, in 2009-2016. The primary outcome measure was the extent of the operation in terms of the height, that is, how often the level cranial to the inferior mesenteric artery (IMA) was achieved. The secondary outcome measures included operation time and surgical outcome.

RESULTS

The majority of operations (n = 239 [84.4%]) were performed for endometrial carcinoma. The most common operation type was robotic-assisted hysterectomy, bilateral salpingo-oophorectomy, and pelvic lymphadenectomy and PALND, which took a median of 3:38 hours or 218 minutes (range, 140-341 minutes) to perform. The high PALND (above the level of IMA) succeeded in 235 operations (83%). In the total cohort, the median number of para-aortic lymph nodes removed was 12 (range, 0-38), with a learning curve approximately more than 40 operations. Para-aortic lymph node metastases were found in 43 patients (15.2%). Seven conversions to laparotomy (2.5%) were done. The conversion and intraoperative complication rates were 2.5% and 3.5%, respectively, and postoperative complications was 18%, according to the classification of Clavien-Dindo. The median length of the postoperative hospital stay was 2 days (range, 1-8 days).

CONCLUSIONS

Using the transperitoneal technique for PALND, the area between IMA and the renal veins can be reached in more than 80% of the operations, with a very low or 2.5% conversion rate.

A feasibility study of sentinel lymph node mapping by cervical injection of a tracer in Japanese women with early stage endometrial cancer

OBJECTIVE

The aim of this study was to investigate the feasibility of sentinel lymph node mapping characterized by a cervical tracer injection in endometrial cancer.

MATERIALS AND METHODS

This retrospective study was carried out using data for 57 patients with endometrial carcinoma who had undergone intraoperative sentinel lymph node mapping and subsequent surgical staging. Technetium colloid and/or indocyanine green was injected into the uterine cervix and a gamma-detecting probe and/or photodynamic eye camera system was used intraoperatively to locate hot spots.

RESULTS

Of the 57 patients, 52 (91.2%) had FIGO Stage I disease. Successful unilateral or bilateral mapping occurred in 54 patients (94.7%) and 46 (80.7%), respectively. The median number of sentinel lymph nodes detected was two (range, 0-5). Following sentinel lymph node mapping, 41 patients (71.9%) underwent pelvic lymphadenectomy alone and 16 (28.1%) full lymphadenectomy. The median number of lymph nodes resected was 17 (range, 8-110). Sentinel lymph nodes were involved in four patients (7.0%), two with macrometastases and two with low-volume metastases. The sensitivity and negative predictive value for detecting lymph node metastasis were both 100%.

CONCLUSION

Sentinel lymph node mapping with the use of cervical tracer injection is highly feasible in Japanese women with early stage endometrial cancer.

Implications of para-aortic lymph node metastasis in patients with endometrial cancer without pelvic lymph node metastasis

Objective

The aim of this study was to confirm the incidence and implications of a lymphatic spread pattern involving para-aortic lymph node (PAN) metastasis in the absence of pelvic lymph node (PLN) metastasis in patients with endometrial cancer.

Methods

We carried out a retrospective chart review of 380 patients with endometrial cancer treated by surgery including PLN dissection and PAN dissection at Hokkaido Cancer Center between 2003 and 2016. We determined the probability of PAN metastasis in patients without PLN metastasis and investigated survival outcomes of PLN−PAN+ patients.

Results

The median numbers of PLN and PAN removed at surgery were 41 (range: 11–107) and 16 (range: 1–65), respectively. Sixty-four patients (16.8%) had lymph node metastasis, including 39 (10.3%) with PAN metastasis. The most frequent lymphatic spread pattern was PLN+PAN+ (7.9%), followed by PLN+PAN− (6.6%), and PLN−PAN+ (2.4%). The probability of PAN metastasis in patients without PLN metastasis was 2.8% (9/325). The 5-year overall survival rates were 96.5% in PLN−PAN−, 77.6% in PLN+PAN−, 63.4% in PLN+PAN+, and 53.6% in PLN−PAN+ patients.

Conclusion

The likelihood of PAN metastasis in endometrial cancer patients without PLN metastasis is not negligible, and the prognosis of PLN−PAN+ is likely to be poor. The implications of a PLN−PAN+ lymphatic spread pattern should thus be taken into consideration when determining patient management strategies.

Surgical treatment of endometrial cancer in developing countries: reasons to consider systematic two-step surgical treatment

OBJECTIVE

The aim of this study was to determine the lymph node status in a large cohort of women with endometrial cancer from the public health system who were referred to an oncology reference center in Brazil to identify candidates for the omission of lymphadenectomy based on clinicopathological parameters.

METHODS

We retrospectively analyzed a cohort of 310 women with endometrial cancer (255 endometrioid, 40 serous, and 15 clear cell tumors) treated between 2009 and 2014. We evaluated the histological type, grade (low vs. high), tumor size (cm), depth of myometrial invasion (≤50%, >50%) and lymphovascular space invasion to determine which factors were correlated with the presence of lymph node metastasis.

RESULTS

The factors related to lymph node involvement were tumor size (p=0.03), myometrial invasion (p<0.01), tumor grade (p<0.01), and lymphovascular space invasion (p<0.01). The histological type was not associated with the nodal status (p=0.52). Only twelve of 176 patients (6.8%) had low-grade endometrioid carcinoma, tumor size ≤2 cm and <50% myometrial infiltration.

CONCLUSIONS

The omission of lymphadenectomy based on the histological type, grade, tumor size and depth of myometrial invasion is not likely to have a large impact on the surgical treatment of endometrial cancer in our population because most patients present with large and advanced tumors. New strategies are proposed that prioritize hysterectomy performed in a general hospital as soon as possible after diagnosis, followed by an evaluation of the need for lymph node dissection at a reference center.

Lymphovascular space invasion and positive pelvic lymph nodes are independent risk factors for para-aortic nodal metastasis in endometrioid endometrial cancer

OBJECTIVE

Para-aortic lymph node dissemination in endometrioid endometrial cancer is uncommon, and systematic para-aortic lymph node dissection increases morbidity. The purpose of this study was to identify a subgroup of endometrioid endometrial cancer patients who did not require para-aortic lymphadenectomy.

STUDY DESIGN

All patients who had undergone surgery for endometrioid endometrial cancer between 1 January 1995 and 31 December 2012 were retrospectively reviewed. Patients with higher risk factors for nodal metastasis and inadequate lymphadenectomy were excluded. Para-aortic lymph node dissemination was defined as nodal metastasis when pelvic and para-aortic lymph node dissection was performed, when para-aortic lymph node recurrence occurred after negative para-aortic lymph node dissection or when para-aortic lymph node dissection was not performed. Multivariate logistic regression models were used to identify the pathological features as predictors for para-aortic lymphatic dissemination.

RESULTS

A total of 827 patients were assessed, 516 (62.4%) of whom underwent pelvic and para-aortic lymph node dissection. Sixty-seven (13%) patients (37 with only pelvic, 26 with pelvic and para-aortic, and 4 with only para-aortic metastasis) had positive lymph nodes in the pelvic and para-aortic lymph node dissection group. Multivariate analysis confirmed positive pelvic nodes (odds ratio 20.58; p<0.001) and lymphovascular space invasion (odds ratio 8.10; p=0.022) as independent predictors of para-aortic lymphatic dissemination. When these two factors were absent (in 83% of patients), the predicted probability of para-aortic lymph node metastasis was 0.1%.

CONCLUSION

Positive pelvic nodes and lymphovascular space invasion are highly associated with para-aortic lymph node metastasis. These markers may be useful for identifying those patients who require para-aortic lymph node dissection.

Robotic transperitoneal infra-renal aortic lymphadenectomy in early-stage endometrial cancer

OBJECTIVES

To assess the clinical performance of robotic-assisted infra-renal aortic lymphadenectomy (IRL) using a single center-docked approach for patients with endometrial cancer.

METHODS

Robotic-assisted hysterectomy with pelvic and aortic lymphadenectomy was performed in 97 clinical stage I endometrial cancer (EC) patients with the intent to remove infra-renal aortic lymph nodes. Peri-operative data was contemporaneously accessioned and a retrospective database analysis was performed to examine clinical outcomes.

RESULTS

IRL versus infra-mesenteric artery (IMA) dissections were accomplished in 88 (90.7%) and nine (9.3%) cases, respectively. There were no laparotomy conversions. Histology included 20.6% G1, 41.2% G2, and 38.1% G3 (endometrioid and Type II histologies). Forty-four (45.4%) cases had >50% depth-of-invasion and 43 (44.3%) cases had lymphovascular space invasion. Lymph node metastases were detected in 39 (40.2%) cases [37 (38.1%) pelvic, 16 (16.5%) pelvic+aortic, two (2.1%) isolated aortic lymph nodes]. Aortic metastasis was identified in 16/37 (43.2%) pelvic node positive cases, and 6/34 (17.7%) IRL cases with positive pelvic nodes had infra-renal metastasis, yet normal aortic nodes below the IMA. Harvested aortic lymph nodes for IRL exceeded IMA cases (15.9±6.3 vs. 8.9±4.6; p<0.01). Mean BMI for IMA cases exceeded IRL cases (37.4±3.3 vs. 31.4±7.1kg/m(2); p<0.001). Twenty-five (81%) patients with BMI >35kg/m(2) underwent successful IRL (range 36-47kg/m(2)) compared to 95% of cases <35kg/m(2) (p=0.03).

CONCLUSIONS

IRL was accomplished in 95% of EC patients with BMI <35kg/m(2) and 81% with BMI >35kg/m(2) using a single center-docked approach. A strict 35kg/m(2) BMI cut-off for avoiding IRL is therefore not advised.

Prospective assessment of the prevalence of pelvic, paraaortic and high paraaortic lymph node metastasis in endometrial cancer

OBJECTIVE

To prospectively define the prevalence of lymph node metastasis (LNM) in at risk endometrial cancer (EC).

METHODS

From 2004 to 2008, frozen section based Mayo Criteria prospectively identified patients "not at-risk" of LNM (30% EC population; grade I/II, <50% myometrial invasion and tumor diameter ≤ 2 cm) where lymphadenectomy was not recommended. The remaining 70% EC cohort was considered "at-risk" of LNM; where a systematic pelvic and infrarenal paraaortic lymphadenectomy was recommended. Patients were prospectively followed. The area between renal vein and inferior mesenteric artery (IMA) was labeled as high paraaortic area. For calculating the prevalence of LNM in high paraaortic area, the denominator was the population with known anatomic location of nodal tissue in relation to the IMA.

RESULTS

Of the 742 patients, 514 were at risk; of which 89% underwent recommended lymphadenectomy. A mean (± standard deviation) of 36 (± 14) pelvic and 18 (± 9) paraaortic nodes were harvested. The prevalence of pelvic and paraaortic LNM was 17% and 12%, respectively. In presence of pelvic LNM, 51% had paraaortic LNM. In absence of pelvic LNM, 3% had paraaortic LNM; of which 67% was located exclusively in high paraaortic area. Among patients with paraaortic LNM, 88% had high paraaortic LNM; and 35% had only high paraaortic LNM. The cases of paraaortic LNM with negative pelvic nodes seemed to cluster in moderate to high grade endometrioid EC with ≥ 50% myometrial invasion.

CONCLUSION

We present reference data for the prevalence of LNM in at-risk EC patients to guide lymphadenectomy decisions for clinical and research purposes.