Exploring isolated tumor cells entity in endometrial cancer

Area of Science:

• Gynecologic Oncology
• Cancer Pathology
• Molecular Oncology

Background:

• Endometrial cancer (EC) management relies on nodal staging and molecular classification.
• The clinical significance of isolated tumor cells (ITC) in EC nodal staging remains unclear.
• Understanding ITC biology is crucial for accurate risk stratification and treatment planning.

Purpose of the Study:

• To characterize the pathological and molecular features of isolated tumor cells (ITC) in endometrial cancer.
• To compare ITC with negative nodal status (N0) and established nodal metastases (N+).
• To evaluate the biological significance of ITC in EC progression.

Main Methods:

• Multicenter, retrospective analysis of 1821 EC patients (June 2018 - May 2024).
• Surgical staging via sentinel lymph node (SLN) biopsy and molecular profiling.
• Comparison of ITC cases (detected by ultrastaging or OSNA) with N0 and N+ groups.

Main Results:

• ITC were found in 5.1% of patients.
• ITC cases showed significantly higher rates of deep myometrial invasion (67.7%) and lymphovascular space invasion (LVSI) (52.1%) compared to N0.
• MMR deficiency was more frequent in ITC (33.3%) vs. N0 (25.0%), while p53 abnormalities were less common in ITC (7.3%) than N+ (19.4%).

Conclusions:

• ITC in EC may represent an early, biologically distinct form of nodal involvement.
• The association with MMR deficiency and lack of p53 abnormalities suggests a potentially less aggressive profile for ITC.
• Integrating molecular and pathological data can refine risk stratification for EC patients with ITC.