High-grade uterine cancer with ambiguous features - a clinicopathological study

Area of Science:

• Gynecologic Oncology
• Pathology
• Cancer Research

Background:

• Endometrial endometrioid carcinoma FIGO grade 3 (EC3) and endometrial serous carcinoma (SEC) can be diagnostically challenging due to overlapping features.
• The prognostic significance of histological subtyping in high-grade endometrial carcinomas remains debated due to conflicting clinical data.

Purpose of the Study:

• To compare clinicopathologic characteristics and prognosis of definite and ambiguous EC3 and SEC cases.
• To investigate the potential of ambiguous cases as an intermediate prognostic group.

Main Methods:

• Retrospective analysis of 129 patients with EC3 and SEC diagnosed between 2006-2022.
• Pathological slide review and classification into definite or ambiguous EC3 and SEC categories.
• Analysis of survival, progression-free survival, and associations between histologic type and clinicopathologic features.

Main Results:

• Definite SEC showed significantly higher mortality than definite EC3 (68.2% vs. 41.4%, p=0.023).
• Ambiguous SEC also exhibited higher mortality than ambiguous EC3 (68.8% vs. 37.5%, p=0.020).
• Ambiguous cases demonstrated intermediate rates of lymph node, broad ligament, and omental involvement compared to definite EC3 and SEC.

Conclusions:

• Ambiguous EC3/SEC cases may represent an intermediate group with more aggressive features than EC3 but more favorable than SEC.
• Identifying this intermediate group has implications for refining prognostic evaluations and treatment strategies in high-grade endometrial carcinomas.