A “stone-like” leiomyoma causing uterine and bowel perforation

A 75-year-old female with a clinical background of hypertension, diabetes mellitus type II, and uterine leiomyoma, presented at our hospital's emergency department with abdominal pain, asthenia, and anorexia. Physical examination revealed a large palpable abdominal mass. Analytically, the patient presented with anaemia and increased inflammatory parameters (Hb 7.4 g/dL; Leucocytosis 14.230 x 10⁹/L).

The patient attended the emergency department twice within one year.

During the first attendance, a calcified leiomyoma was diagnosed with different radiological studies. The abdominal radiograph showed a calcified pelvic mass (Figure 1). The transvaginal ultrasound was a suboptimal examination, due to extensive calcification in the myometrium and significant posterior acoustic shadowing (Figure 2). Computed tomography (CT) and Magnetic Resonance Imaging (MRI) were further obtained, confirming the presence of an unusually massive and calcified uterine leiomyoma, which was causing mild uretero-hydronephrosis in the right kidney (Figures 3-5). Hysterectomy and double adnexectomy were proposed, which were later refused by the patient, due to clinical improvement.

At the second time of attendance in the emergency department, a CT scan was repeated, and it showed gas bubbles in the periphery of the calcified leiomyoma, suggestive of infection (pyomyoma) and eventually uterine perforation (Figure 6). There was no evidence of free liquid, pneumoperitoneum or other abdominal findings.

Uterine leiomyomas (LMs) are the most frequent gynaecologic neoplasm and the most common uterine tumour in women, with a prevalence reaching 70%-80% among women with 50 years-old and older [1,2]. According to the World Health Organization (WHO) classification of Female Genital Tumours updated in 2020, leiomyomas can be categorized as Usual-type leiomyoma or by their different subtypes (Cellular leiomyoma; Leiomyoma with bizarre nuclei; Fumarate hydratase (FH) deficient leiomyoma; Mitotically active leiomyoma; Hydropic leiomyoma; Apoplectic leiomyoma; Lipoleiomyoma; Epithelioid leiomyoma; Myxoid leiomyoma; Cotyledonoid dissecting leiomyoma; Diffuse leiomyomatosis) [3,4].

LMs are hormonally dependent; they develop after menarche and tend to regress after menopause [5,6]. Incidence is higher in African-American patients [5]. Additional risk factors include early menarche, diet elements (red meat, caffeine, alcohol), genetic factors (eg., hereditary leiomyomatosis and renal cell carcinoma syndrome), and molecular alterations (most frequently MED12(Xq13.1), HMGA2(12q15), and HMGA(6q21) mutations) [4,5].

Symptoms occur in 20-50% of women and can be dysmenorrhea, menorrhagia, pelvic pressure, reproductive dysfunction, dyspareunia [5-7]. Urological symptoms may also occur, such as ureteral obstruction/hydronephrosis, lower urinary tract symptoms (LUTS), vesicouterine fistula, renal failure, haematuria, and neurogenic bladder [8]. In our patient, the leiomyoma was causing ureteral obstruction with mild hydronephrosis (Figure 4).

Uterine LMs tend to calcify in the absence of vascular supply, especially in post-menopausal women and are associated with end-stage hyaline degeneration, as well as uterine artery embolization [6,9]. Over time, calcium phosphates and carbonates deposit in the leiomyoma, due to diminishing blood supply and ischemic tissue necrosis [9,10]. At imaging, a calcified LM may appear with a popcorn or mottled appearance, peripheral calcification, and totally calcified as a stony mass [9].

An infected LM (pyomyoma) is associated in most cases with uterine artery embolization and post-menopausal period, especially in those with hypertension, diabetes, and atherosclerosis [11-13]. Its diagnosis must be considered in the presence of leiomyoma, sepsis, and absence of other infected tissues [12]. On CT scans and MRIs, pyomyomas may show an increased fluid level, debris, gas bubbles, and wall thickness with rim enhancement [12]. This clinical entity requires prompt antibiotic treatment and surgical management, otherwise, it may lead to fatal complications, such as peritonitis and sepsis [12,14].

Small bowel obstruction and perforation are rare presentations of parasitic LMs attached to the small bowel, omentum, and pelvic side wall [15-17].

In our patient, a laparotomy with hysterectomy, double adnexectomy, and partial ileal resection was performed and revealed a uterine “stone-like” mass, attached to the anterior parietal peritoneum, omentum, and small bowel loops, massively infiltrating one of the loops. Histopathologically, the uterus and terminal ileum presented areas of ulceration, necrosis, and expressive acute and chronic inflammation (Figure 7). Uterine and terminal ileum perforation was documented (probably due to mechanical aetiology from friction by the large and calcified leiomyoma with spiculated surfaces). No malignancy was detected. It was impossible to cut and process histologically the “stone-like” leiomyoma due to its intense calcification.

After surgery, the patient presented a good clinical evolution.

Written informed patient consent for publication has been obtained.