Adenomyosis and Endometrial Carcinoma-Prognostic Significance of Coexistence. A Retrospective Analysis

Although frequently identified in hysterectomy specimens of women with endometrial carcinoma, the impact of adenomyosis on the prognosis of endometrial carcinoma remains uncertain. Therefore, we aimed to evaluate the prognostic significance of coexistent adenomyosis and endometrial carcinoma, focusing on histopathological features, staging, and recurrence rates.

We conducted a retrospective analysis of 142 women treated during 2013-2023 for endometrial carcinoma, categorized as Type 1 or Type 2. Clinical, histopathological, and recurrence data were compared between those with and without adenomyosis.

Adenomyosis was identified in 32/142 women (22.5%). Among 119 with Type 1 endometrial carcinoma, 26 (21.8%) had adenomyosis. FIGO stage I-II disease was present in all of these and in 76/93 (81.7%) of those without adenomyosis (p = 0.022). Cervical stroma was less frequently involved in the adenomyosis group (1/26; 3.8% vs 17/93; 18.3%, p = 0.05). Among the 23 women with Type 2 endometrial carcinoma, stage and recurrence rates did not differ significantly between those with and without adenomyosis. In histopathological assessment, malignant cells within adenomyotic foci were identified in six patients: five with Type 1 and one with Type 2 carcinoma. All of these involved deep diffuse adenomyosis. Strong PAX8 positivity was found in four women, and estrogen receptor positivity in five.

We report an independent association of adenomyosis in Type 1 endometrial carcinoma with earlier-stage disease and reduced cervical stroma involvement. These findings highlight a potential association between adenomyosis and favorable tumor characteristics, warranting further studies to clarify the prognostic significance.