The prognostic significance of aortic lymph node metastasis in endometrial cancer: Potential implications for selective aortic lymph node assessment

Identifying safe diagnostic algorithms for sentinel lymph node mapping in high-risk endometrial cancer: The SENTIREC-endo study

INTRODUCTION

It is unclear if sentinel node (SLN) mapping can replace pelvic- (PLD) and paraaortic lymphadenectomy (PALD) for high-risk endometrial cancer (EC). A diagnostically safe surgical algorithm, taking failed mapping cases into account, is not defined. We aimed to investigate the diagnostic accuracy of SLN mapping algorithms in women with exclusively high-risk EC.

METHODS

We undertook a prospective national diagnostic cohort study of SLN mapping in women with high-risk EC from March 2017 to January 2023. The power calculation was based on the negative predictive value (NPV). Women underwent SLN mapping, PLD and PALD besides removal of suspicious and any FDG/PET-positive lymph nodes. Accuracy analyses were performed for five algorithms.

RESULTS

170/216 included women underwent SLN mapping, PLD and PALD and were included in accuracy analyses. 42/170 (24.7%) had nodal metastasis. The algorithm SLN and PLD in case of failed mapping, demonstrated a sensitivity of 86% (95% CI 74-100) and an NPV of 96% (95% CI 91-100). The sensitivity increased to 93% (95% CI 83-100) and the NPV to 98% (95% CI 94-100) if PLD was combined with removal of any PET-positive lymph nodes. Equivalent results were obtained if PLD and PALD were performed in non-mapping cases; sensitivity 93% (95% CI 83-100) and NPV 98% (95% CI 95-100).

CONCLUSION

SLN-mapping is a safe staging procedure in women with high-risk EC if strictly adhering to a surgical algorithm including removal of any PET-positive lymph nodes independent of location and PLD or PLD and PALD in case of failed mapping.

Construction and validation of a prognostic model for stage IIIC endometrial cancer patients after surgery

BACKGROUND

To explore the most predictive lymph node (LN) scheme for stage IIIC endometrial cancer (EC) patients after hysterectomy and develop a scheme-based nomogram.

METHODS

Data from 2626 stage IIIC EC patients, diagnosed between 2010 and 2014, were extracted from the Surveillance, Epidemiology, and End Results (SEER) registry. The predictive ability of four LN schemes was assessed using C-index and Akaike information criterion (AIC). A nomogram based on the most predictive LN scheme was constructed and validated. The comparison of the predictive ability between nomogram and FIGO stage was conducted using the area under the receiver operating characteristic curve (AUC) and decision curve analysis (DCA).

RESULTS

FIGO stage (stage IIIC1/stage IIIC2) was not an independent risk factor for OS in stage IIIC EC patients (P = 0.672) and log odds of positive lymph nodes (LODDS) had the best predictive ability (C-index: 0.742; AIC: 8228.95). A nomogram based on LODDS was constructed and validated, which had a decent C-index of 0.742 (0.723-0.762). The nomogram showed a better predictive ability than that of the FIGO staging system.

CONCLUSION

FIGO IIIC1/FIGO IIIC2 could not differentiate the prognosis for stage IIIC EC patients. We developed and validated a nomogram based on LODDS to predict OS for post-operative patients with stage IIIC EC.

Detection of the sentinel lymph node with hybrid tracer (ICG-[99mTc]Tc-albumin nanocolloid) in intermediate- and high-risk endometrial cancer: a feasibility study

PURPOSE

Indocyanine green (ICG) is frequently used for the detection of the sentinel lymph node (SLN) in gynecology, but it carries the loss of the presurgical SLN mapping provided by [99mTc]-based colloids. Hybrid tracers such as ICG-[99mTc]Tc-albumin nanocolloid combine the benefits of both components. The aim of this study was to evaluate the feasibility and applicability of this hybrid tracer injected by transvaginal ultrasound-guided myometrial injection of radiotracer (TUMIR) approach in the detection of SLNs in patients with intermediate- and high-risk EC.

METHODS

Fifty-two patients with intermediate- and high-risk EC underwent SLN biopsy after injection of a hybrid tracer using the TUMIR approach, followed by pelvic and paraaortic lymphadenectomy. SLNs were detected preoperatively by lymphoscintigraphic study and intraoperatively by gamma probe and near-infrared (NIR) optical laparoscopic camera.

RESULTS

Preoperative lymphatic drainage was obtained in 69% and intraoperative detection in 71.4% of patients. A total of 146 SLNs (4.17 SLNs/patient) were biopsied. Pelvic bilateral detection was observed in 57% of the women and paraaortic drainage in 34% of the patients. The radioactive component allowed the detection of SLN in 97.1% of the patients, while the fluorescent component detected 80%. In more than 17% of the patients with intraoperative detection, SLNs were detected only by the radioactive signal. Lymph node metastasis was identified in 14.3% of patients submitted to SLNB. The sensitivity and negative predictive value for metastatic involvement were 100%.

CONCLUSION

TUMIR injection of a hybrid tracer in patients with intermediate- and high-risk EC combines the benefits of the radiotracer and the fluorescence methods with a single tracer. The method increases the paraaortic detection rate and allows a potential increase in SLN detection. Notwithstanding, based on our findings, the radioactive component of the hybrid tracer cannot be obviated.

Paraaortic sentinel lymph node detection in intermediate and high-risk endometrial cancer by transvaginal ultrasound-guided myometrial injection of radiotracer (TUMIR)

Objective

We aimed to evaluate the accuracy of sentinel lymph node (SLN) mapping with transvaginal ultrasound-guided myometrial injection of radiotracer (TUMIR) to detect lymph node (LN) metastases, in patients with intermediate and high-risk endometrial cancer (EC), focusing on its performance to detect paraaortic involvement.

Methods

Prospective study including women with preoperative intermediate or high-risk EC, according to ESMO-ESGO-ESTRO consensus, who underwent SLN mapping using the TUMIR approach. SLNs were preoperatively localized by planar and single photon emission computed tomography/computed tomography images, and intraoperatively by gamma-probe. Immediately after SLN excision, all women underwent systematic pelvic and paraaortic lymphadenectomy by laparoscopy.

Results

The study included 102 patients. The intraoperative SLN detection rate was 79.4% (81/102). Pelvic and paraaortic drainage was observed in 92.6% (75/81) and 45.7% (37/81) women, respectively, being exclusively paraaortic in 7.4% (6/81). After systematic lymphadenectomy, LN metastases were identified in 19.6% (20/102) patients, with 45.0% (9/20) showing paraaortic involvement, which was exclusive in 15.0% (3/20). The overall sensitivity and negative predictive value (NPV) of SLNs by the TUMIR approach to detect lymphatic involvement were 87.5% and 97.0%, respectively; and 83.3% and 96.9%, for paraaortic metastases. After applying the MSKCC SLN mapping algorithm, the sensitivity and NPV were 93.8% and 98.5%, respectively.

Conclusion

The TUMIR method provides valuable information of endometrial drainage in patients at higher risk of paraaortic LN involvement. The TUMIR approach showed a detection rate of paraaortic SLNs greater than 45% and a high sensitivity and NPV for paraaortic metastases in women with intermediate and high-risk EC.

A Lymph Node Count-Based AJCC Staging System Facilitates a More Accurate Prediction of the Prognosis of Patients With Endometrial Cancer

Purpose

Both the International Federation of Gynecology and Obstetrics (FIGO) and the American Joint Committee on Cancer (AJCC) staging system for endometrial cancer (EC) defined the N category by the location of metastatic lymph nodes (LNs) rather than the metastatic LN count. We aimed to compare the accuracy of the AJCC staging system and the LN count-based staging system.

Patients and Methods

EC patients were selected from the Surveillance, Epidemiology and End Results (SEER) database between 2004 and 2016. Patients' characteristics were collected, including age, race, marital status, histological type, grade, therapeutic measures, the number of metastatic LNs, the number of dissected LNs, vital status, and survival in months. Overall survival (OS) was analyzed by the Kaplan-Meier (KM) method and the concordance index (C-index) was used to compare the prognostic value of the AJCC staging system and the LN count-based staging system.

Results

We identified 4,276 EC cases from the SEER database, including 2,693 patients with stage IIIC1 and 1,583 patients with stage IIIC2. Multivariate analyses showed that independent prognostic factors for patients with stage IIIC1 included age, race, marital status, grade, histology, chemotherapy, and radiotherapy. Independent prognostic factors for patients with stage IIIC2 included age, marital status, grade, histology, chemotherapy, and radiotherapy. The C-index of the AJCC staging system and the LN count-based staging system were 0.483 and 0.617, respectively. At least six LNs should be dissected to ensure the accuracy of the LN count-based staging system.

Conclusion

A modified AJCC staging system based on the count of metastatic LNs might be superior to the current AJCC staging system, which still had room for improvement and further refinements were required. For accurate staging, we recommended that at least six LNs should be examined in the modified AJCC staging system.

Establishment and evaluation of a risk-scoring system for lymph node metastasis in early-stage endometrial carcinoma: Achieving preoperative risk stratification

AIM

To establish a risk-scoring system for lymph node metastasis (LNM) of early-stage endometrial carcinoma (EC), and to stratify the preoperative risk of LNM.

METHODS

We retrospectively analyzed the clinical data of 507 patients diagnosed with the early-stage EC (i.e., confined to the uterine corpus). We determined the risk factors for LNM by logistic regression analysis; then constructed a simple logistic scoring system, and an additive scoring system based on the regression coefficient (β), and odds ratio, of each variable, respectively.

RESULTS

The overall rate of LNM was 9.1% (46/507). Multivariate analysis showed that preoperative serum cancer antigen 125 (CA125) ≥35 U/mL, histopathology of grade 3 and/or type II, depth of myometrial invasion ≥1/2 and positive immunostaining for Ki-67 ≥50%, were independent risk factors for LNM (P < 0.05). The simple logistic and additive scoring systems exhibited good predictive ability (area under the curve [AUC] >0.8). Based on the additive scoring system, the risk of LNM in patients with early-stage EC was classified into three groups: a low-risk group (total score: <5), an intermediate-risk group (total score: 5-10) and a high-risk group (total score: >10). The incidence of LNM differed significantly across these three groups (P < 0.05).

CONCLUSION

The risk-scoring system constructed in this study can effectively predict the risk of LNM in patients with early-stage EC, achieve preoperative risk stratification and provide a reference guideline for the use of lymphadenectomy.

Subdivision of IIIC Stage for Endometrioid Carcinoma to Better Predict Prognosis and Treatment Guidance

Objective: The prognostic value of Fédération Internationale de Gynécologie et d'Obstétrique (FIGO) IIIC staging in endometrioid carcinoma patients remains debatable. The current study aimed to compare the prognosis between IIIC1 and IIIC2 patients with endometrioid carcinoma and attempt to conduct a new subdivision.

Methods: By using the Surveillance, Epidemiology, and End Results (SEER) database, patients with endometrioid-type endometrial cancer diagnosed from 2004 to 2015 were identified and randomly divided into training and validation sets. We developed a Fine–Gray competing risk model to compare the cancer-specific mortality (CSM). The IIIC subdivision system was built based on the independent prognostic factors. The cumulative incidence curves were compared using Gray's test or log-rank test. Nomogram for predicting 3- or 5-years CSM was constructed and subsequently validated internally and externally.

Results: The IIIC subdivision defined by FIGO staging, including IIIC1 and IIIC2, exhibited no association with CSM in multivariate analysis [subdistribution hazard ratio [SHR] = 1.03, 95% CI [0.85–1.26], P = 0.760]. The IIIC category was subdivided into three subcategories based on the tumor (T) and nodes (N) stage, including IIICa (T1N1 and T1N2), IIICb (T2N1 and T2N2), and IIICc (T2N1 and T2N2). The prognosis across new IIIC subcategories with CSM remained significant [IIICb vs. IIICa: SHR = 1.53, 95% CI [1.18–1.98], P = 0.001; IIICc vs. IIICa: SHR = 2.64, 95% CI [2.13–3.28], P < 0.001]. Postoperative adjuvant chemotherapy or radiotherapy alone did not improve survival for patients categorized as IIICa or IIICb, and all IIIC patients benefited most from combination of postoperative chemotherapy and radiotherapy [IIICa: SHR = 0.59, 95% CI [0.43–0.82], P = 0.001; IIICb: SHR = 0.66, 95% CI [0.45–0.97], P = 0.036; IIICc: SHR = 0.44, 95% CI [0.34–0.58], P < 0.001]. A nomogram based on competing risk model was built to predict the long-term survival of IIIC patients, with a concordance index above 0.70 both in training and validation set.

Conclusion: There was no prognostic difference between FIGO IIIC1 and IIIC2 patients with endometrioid-type endometrial cancer. A new subdivision of IIIC category facilitates prognosis prediction and treatment modalities. A combination of postoperative chemotherapy and radiotherapy exerted as the optimal choice for endometrioid cancer patients with IIIC stage.

The characteristics of isolated para-aortic lymph node metastases in endometrial cancer and their prognostic significance

Background

The aim of this study was to clarify the features and prognostic significance of isolated para-aortic lymphatic metastasis of endometrial cancer.

Methods

A retrospective study of patients with stage IIIC endometrial cancer was performed based on the Surveillance, Epidemiology, and End Results (SEER) database. A total of 2767 patients were divided into three groups according to the lymphatic metastasis patterns: isolated pelvic lymphatic metastasis, isolated para-aortic lymphatic metastasis and dual lymphatic metastasis. The clinic-pathological characteristics and prognosis of patients were compared among the three groups.

Result

The proportion of patients with isolated para-aortic lymphatic metastasis was 13.70%. Patients with isolated pelvic lymphatic metastasis or isolated para-aortic lymphatic metastasis shared similar histological characteristics, except that patients with isolated para-aortic lymphatic metastasis had a lower proportion of tumors over 5 cm in diameter than patients with isolated pelvic lymphatic metastasis (35.1% versus 45.7%, p = 0.001). Compared with patients with dual lymphatic metastasis, isolated para-aortic lymphatic metastasis was more common in patients with endometrioid tumors (78.6% versus 67.3%, p < 0.001), grade 1-2 cancers (53.3% versus 36.3%, p < 0.001) and negative peritoneal cytology (76.2% versus 61.1%, p < 0.001). Dual lymphatic metastasis was an independent predictive factor for the poor outcomes of patients at stage IIIC. However, in stage IIIC endometrioid tumors, patients with isolated pelvic lymphatic metastasis and those with isolated para-aortic lymphatic metastasis shared similar prognosis. Patients at stage IIIC with nonendometrioid tumors and patients at stage IV could not be further divided into subgroups according to lymphatic metastasis patterns in terms of prognosis.

Conclusion

Endometrioid patients with isolated pelvic lymphatic metastasis and isolated para-aortic lymphatic metastasis share similar clinical pathological characteristics and prognoses.

Optimizing the treatment algorithm for sentinel lymph node mapping in endometrial cancer

The incidence of endometrial cancer, the most common gynecological malignancy, is increasing as life expectancy and obesity both rise. Lymph node status is the most important predictor for outcome, yet routine lymphadenectomy does not confer a survival benefit and is associated with substantial surgical morbidity. In the last decade, sentinel lymph node (SLN) mapping has emerged as a feasible and accurate alternative to full lymphadenectomy. Yet, SLN has introduced a distinction between micro- and macrometastasis, and the entity of non-SLN involvement with their attendant impact on outcome. Included among the raised issues is the question of whether positive sentinel nodes should be followed by pelvic and/or para-aortic lymphadenectomy dependent on the presence of macrometastasis at frozen section or other criteria. Moreover, the proper adjuvant treatment for individual cases with micrometastasis and/or isolated tumor cells is unclear. Recently published data on this topic are summarized in order to optimize the current treatment algorithm as it relates to the results of SLN assessment in endometrial cancer.

Clinicopathological study of organ metastasis in endometrial cancer

Aim: Our aim was to analyze the clinicopathological features of lung, liver, bone and brain metastasis in patients with endometrial cancer (EC). Patients & methods: We screened patients diagnosed with EC between 2010 and 2015 from the Surveillance, Epidemiology and End Results database. Results: Among 69,027 eligible EC patients, lung metastasis was the most common. Patients with lung or liver metastasis were at higher risk of bone and brain metastases than those without lung and liver metastasis. Brain metastasis has the lowest survival time (5.0 months) in single organ metastasis. Liver and brain metastasis have the highest death rate in two organ metastasis, and lung, liver and brain metastasis had the lowest survival time (1.0 month) in multi-sites metastasis. Conclusion: Lung metastasis was the most common in EC patients. Assessing distant organ metastasis may help clinicians to determine appropriate follow-up strategy for patients with EC.

Comparison of outcomes between the one-step and two-step sentinel lymph node mapping techniques in endometrial cancer

INTRODUCTION

Fluorescence image-guided sentinel lymph node (SLN) biopsy using a two-step mapping technique incorporates sequential injection of indocyanine green into the bilateral uterine cornus, followed by cervical injection. Outcomes were compared with the conventional cervical (one-step) method .

METHODS

Patients with FIGO stage I-III endometrial cancer who underwent laparoscopic or robotic staging, including SLN biopsy, from May 2014 to December 2018, were retrospectively reviewed. Patient characteristics, pre-operative imaging, SLN detection pattern, pathologic result, adjuvant, and recurrence locations were analyzed.

RESULTS

A total of 199 patients received one-step (n=123) and two-step (n=76) SLN biopsy. Para-aortic SLN were more frequently identified in the two-step group. Lower and upper para-aortic SLN were identified in 67.1% and 38.2%, respectively, in the two-step group and in 18.7% and 5.7% in the one-step group (p<0.001). The number of para-aortic SLN harvested was superior in the two-step group (p<0.001). Metastatic para-aortic SLN were found in 7.9% of the two-step group and 2.4% of the one-step group (p=0.070). In detecting nodal metastasis, the sensitivities of the one- and two-step methods were 91.7% and 100.0%, negative predictive values were 99.0% and 100.0%, false-negative rates were 8.3% and 0%, and accuracy rates were 99.1% and 100.0%, respectively. The one-step method identified only three out of eight para-aortic lymph node metastases and missed five para-aortic lymph node metastases. There was no missed para-aortic lymph node metastasis in the two-step group. Recurrence was observed in two patients (2.6%; vaginal vault and adrenal gland) in the two-step group and seven patients (5.7%) including three nodal recurrences in the one-step group (p=0.307).

DISCUSSION

Two-step SLN mapping improved the para-aortic SLN detection rate, a known pitfall of conventional cervical injection. Proper evaluation of aortic nodal status will assist in the tailoring of adjuvant and prevent undertreatment of patients with isolated para-aortic metastasis.

Sentinel lymph node mapping in endometrial cancer: performance of hysteroscopic injection of tracers

OBJECTIVE

To report on the performance of hysteroscopic injection of tracers (indocyanine green (ICG) and technetium-99m (Tc-99m)) for sentinel lymph node (SLN) mapping in endometrial cancer.

METHODS

Single-center retrospective evaluation of consecutive patients who underwent SLN mapping following hysteroscopic peritumoral injection of tracer. Detection rate (overall/bilateral/aortic) diagnostic accuracy, and oncologic outcomes were evaluated.

RESULTS

A total of 221 procedures met the inclusion criteria. Mean patient age was 60 (range 28-84) years and mean body mass index was 26.9 (range 15-47) kg/m² . In 164 cases (70.9%) mapping was performed laparoscopically. The overall detection rate of the technique was 94.1% (208/221 patients). Bilateral pelvic mapping was found in 62.5% of cases with at least one SLN detected and was more frequent using ICG than with Tc-99m (73.8% vs 53.3%; p<0.001). In 47.6% of cases SLNs mapped in both pelvic and aortic nodes, and in five cases (2.4%) only in the aortic area. In eight patients (3.8%) SLNs were found in aberrant (parametrial/presacral) areas. Mean number of detected SLNs was 3.7 (range 1-8). In 51.9% of cases at least one node other than SLNs was removed. Twenty-six patients (12.5%) had nodal involvement: 12 (46.2%) macrometastases, six (23.1%) micrometastases, and eight (30.7%) isolated tumor cells. In 12 cases (46.8%) the aortic area was involved. Overall, 6/221 (2.7%) patients had isolated para-aortic nodes. Three false-negative results were found, all in the Tc-99m group. All had isolated aortic metastases. Overall sensitivity was 88.5% (95% CI 71.7 to 100.0) and overall negative predictive value was 96.5% (95% CI 86.8 to 100.0). There were 10 (4.8%) recurrences: five abdominal/distant, four vaginal, and one nodal (in the aortic area following a unilateral mapping plus side-specific pelvic lymphadenectomy). Most recurrences (9/10 cases) were patients in whom a completion lymphadenectomy was performed. No deaths were reported after a mean follow-up of 47.7 months.

CONCLUSIONS

Hysteroscopic injection of tracers for SLN mapping in endometrial cancer is as accurate as cervical injection with a higher detection rate in the aortic area. ICG improves the bilateral detection rate. Adding lymphadenectomy to SLN mapping does not reduce the risk of relapse.