Clinical Features and Imaging Findings of Low-Grade Endometrial Stromal Sarcoma: A Retrospective Case Series-Based Analysis.

OBJECTIVE

This case series presents six cases of low-grade endometrial stromal sarcoma (LGESS) and discusses their magnetic resonance imaging (MRI) findings in light of recent advancements in LGESS diagnosis.

METHODS

Data from six cases of LGESS treated at Fukui University Hospital between June 2007 and October 2024 were retrospectively analyzed. The clinical behavior, histopathological features, therapeutic approaches, and survival outcomes were evaluated. MRI images were assessed by two radiologists over multiple parameters that were considered specific to the LGESS.

RESULTS

Among the six patients with LGESS, four patients had tumors located within the myometrium, whereas two patients had tumors located in the submucosal layer. All cases were classified as International Federation of Gynecology and Obstetrics Stage Ⅰ, and no recurrence was observed during follow-up. On MRI, all six tumors exhibited high signal intensity on T2-weighted images (T2WI), compared to the myometrium, and high signal intensity on diffusion-weighted images (DWI), compared to the endometrium. In four of the five evaluable cases, the mean apparent diffusion coefficient (ADC) value was 0.86 × 10⁻³ mm²/s (range: 0.81-0.99).

CONCLUSION

Both clinically and based on imaging findings, distinguishing between LGESS and rare leiomyoma variants is challenging. MRI findings, including high signal intensity on T2WI and DWI as well as low ADC values, may prove valuable in differentiating these two entities.