Assessing the role of low volume disease in endometrial cancer

Prognostic value of isolated tumor cells in sentinel lymph nodes in low risk endometrial cancer: results from an international multi-institutional study

OBJECTIVE

The prognostic significance of isolated tumor cells (≤0.2 mm) in sentinel lymph nodes (SLNs) of endometrial cancer patients is still unclear. Our aim was to assess the prognostic value of isolated tumor cells in patients with low risk endometrial cancer who underwent SLN biopsy and did not receive adjuvant therapy. Outcomes were compared with node negative patients.

METHODS

Patients with SLNs-isolated tumor cells between 2013 and 2019 were identified from 15 centers worldwide, while SLN negative patients were identified from Mayo Clinic, Rochester, between 2013 and 2018. Only low risk patients (stage IA, endometrioid histology, grade 1 or 2) who did not receive any adjuvant therapy were included. Primary outcomes were recurrence free, non-vaginal recurrence free, and overall survival, evaluated with Kaplan-Meier methods.

RESULTS

494 patients (42 isolated tumor cells and 452 node negative) were included. There were 21 (4.3%) recurrences (5 SLNs-isolated tumor cells, 16 node negative); recurrence was vaginal in six patients (1 isolated tumor cells, 5 node negative), and non-vaginal in 15 (4 isolated tumor cells, 11 node negative). Median follow-up among those without recurrence was 2.3 years (interquartile range (IQR) 1.1-3.0) and 2.6 years (IQR 0.6-4.2) in the SLN-isolated tumor cell and node negative patients, respectively. The presence of SLNs-isolated tumor cells, lymphovascular space invasion, and International Federation of Obstetrics and Gynecology (FIGO) grade 2 were significant risk factors for recurrence on univariate analysis. SLN-isolated tumor cell patients had worse recurrence free survival (p<0.01) and non-vaginal recurrence free survival (p<0.01) compared with node negative patients. Similar results were observed in the subgroup of patients without lymphovascular space invasion (n=480). There was no difference in overall survival between the two cohorts in the full sample and the subset excluding patients with lymphovascular space invasion.

CONCLUSIONS

Patients with SLNs-isolated tumor cells and low risk profile, without adjuvant therapy, had a significantly worse recurrence free survival compared with node negative patients with similar risk factors, after adjusting for grade and excluding patients with lymphovascular space invasion. However, the presence of SLNs-isolated tumor cells was not associated with worse overall survival.

Accuracy and Survival Outcomes after National Implementation of Sentinel Lymph Node Biopsy in Early Stage Endometrial Cancer

BACKGROUND

Sentinel lymph node (SLN) biopsy has recently been accepted to evaluate nodal status in endometrial cancer at early stage, which is key to tailoring adjuvant treatments. Our aim was to evaluate the national implementation of SLN biopsy in terms of accuracy to detect nodal disease in a clinical setting and oncologic outcomes according to the volume of nodal disease.

PATIENTS AND METHODS

A total of 29 Spanish centers participated in this retrospective, multicenter registry including patients with endometrial adenocarcinoma at preoperative early stage who had undergone SLN biopsy between 2015 and 2021. Each center collected data regarding demographic, clinical, histologic, therapeutic, and survival characteristics.

RESULTS

A total of 892 patients were enrolled. After the surgery, 12.9% were suprastaged to FIGO 2009 stages III-IV and 108 patients (12.1%) had nodal involvement: 54.6% macrometastasis, 22.2% micrometastases, and 23.1% isolated tumor cells (ITC). Sensitivity of SLN biopsy was 93.7% and false negative rate was 6.2%. After a median follow up of 1.81 years, overall surivial and disease-free survival were significantly lower in patients who had macrometastases when compared with patients with negative nodes, micrometastases or ITC.

CONCLUSIONS

In our nationwide cohort we obtained high sensitivity of SLN biopsy to detect nodal disease. The oncologic outcomes of patients with negative nodes and low-volume disease were similar after tailoring adjuvant treatments. In total, 22% of patients with macrometastasis and 50% of patients with micrometastasis were at low risk of nodal metastasis according to their preoperative risk factors, revealing the importance of SLN biopsy in the surgical management of patients with early stage EC.

The Sentinel Lymph Node in Treatment Planning: A Narrative Review of Lymph-Flow-Guided Radiotherapy

The sentinel lymph node technique is minimally invasive and used routinely by surgeons, reducing the need for morbid extensive lymph node dissections, which is a significant advantage for cancer staging and treatment decisions. The sentinel lymph node could also help radiation oncologists to identify tumor drainage for each of their patients, leading to a more personalized radiotherapy, instead of a probabilistic irradiation based on delineation atlases. The aim is both to avoid recurrence in unexpected areas and to limit the volume of irradiated healthy tissues. The aim of our study is to evaluate the impact of sentinel lymph node mapping for radiation oncologists. This concept, relying on sentinel lymph node mapping for treatment planning, is known as lymph-flow-guided radiotherapy. We present an up-to-date narrative literature review showing the potential applications of the sentinel lymph node technique for radiotherapy, as well as the limits that need to be addressed before its routine usage.

Role of Genomic and Molecular Biology in the Modulation of the Treatment of Endometrial Cancer: Narrative Review and Perspectives

Endometrial cancer (EC) is one of the most common gynecological malignancies in Western countries. Traditionally, loco-reginal dissemination and histological characteristics are the main prognostic factors. Nowadays, molecular and genomic profiling showed exciting results in terms of prognostication. According to the data provided by The Cancer Genome Atlas and other studies, molecular and genomic profiling might be useful in identifying patients al low, intermediate, and high risk of recurrence. However, data regarding the therapeutic value are scant. Several prospective studies are ongoing to identify the most appropriate adjuvant strategy in EC patients, especially for those with positive nodes and low volume disease. The molecular classification has offered the possibility to improve the risk stratification and management of EC. The aim of this review is to focus on the evolution of molecular classification in EC and its impact on the research approach and on clinical management. Molecular and genomic profiling might be useful to tailor the most appropriate adjuvant strategies in apparent early-stage EC.

Evaluating long-term outcomes of three approaches to retroperitoneal staging in endometrial cancer

OBJECTIVE

Sentinel lymph node mapping (SNM) has gained popularity in managing apparent early-stage endometrial cancer (EC). Here, we evaluated the long-term survival of three different approaches of nodal assessment.

METHODS

This is a multi-institutional retrospective study evaluating long-term outcomes of EC patients having nodal assessment between 01/01/2006 and 12/31/2016. In order to reduce possible confounding factors, we applied a propensity-matched algorithm.

RESULTS

Overall, 940 patients meeting inclusion criteria were included in the study, of which 174 (18.5%), 187 (19.9%), and 579 (61.6%) underwent SNM, SNM followed by backup lymphadenectomy (LND) and LND alone, respectively. Applying a propensity score matching algorithm (1:1:2) we selected 500 patients, including 125 SNM, 125 SNM/backup LND, and 250 LND. Baseline characteristics of the study population were similar between groups. The prevalence of nodal disease was 14%, 16%, and 12% in patients having SNM, SNM/backup LND and LND, respectively. Overall, 19 (7.6%) patients were diagnosed with low volume nodal disease. The survival analysis comparing the three techniques did not show statistical differences in terms of disease-free (p = 0.750) and overall survival (p = 0.899). Similarly, the type of nodal assessment did not impact survival outcomes after stratification based on uterine risk factors.

CONCLUSION

Our study highlighted that SNM provides similar long-term oncologic outcomes than LND.