Leiomyoma development in Mayer–Rokitansky–Küster–Hauser (MRKH) syndrome with a rudimentary uterus

A 35-year-old woman with MRKH syndrome, who was diagnosed at the age of 15 following a primary amenorrhea study. Previous ultrasonography showed uterine and left renal agenesis. As the only previous surgery, the patient underwent a vaginoplasty at the age of 21, due to congenital vaginal agenesis.

The patient was referred to our hospital, asymptomatic, for a urinary system ultrasound follow-up.

Abdominopelvic ultrasound (Figure 1) showed a heterogeneous nodular lesion with well-defined borders, measuring 10.3 x 9.9 cm (diameters: transverse and anteroposterior), located in the pelvis. Transvaginal ultrasound (Figures 2 and 3) provided a clearer view of the lesion. Only one well-defined ovary was visualised in the pelvis, which was reported as the right ovary. The left ovary was not clearly depicted.

On the contrast-enhanced abdominopelvic CT scan (Figures 4, 5, 6 and 7; axial, coronal, and sagittal, respectively), a well-defined nodular lesion centred in the pelvis (supravesical), of similar dimensions to the ultrasounds, was observed. The ovaries were not clearly identified in the pelvis. However, a structure in the right iliac fossa compatible with an ectopic ovary was visualised. No uterus was observed.

Histological examination (Figures 8 and 9) of the lesion revealed tissue with well-defined architecture, fascicles of orderly smooth muscle cells, regular nuclei, and cytoplasm. The presence of interstitial collagen and acceptable mitotic activity without necrotic areas were noted. The study concluded that the findings were consistent with a leiomyoma of a rudimentary uterus.

Mayer–Rokitansky–Küster–Hauser syndrome is a sexual developmental disorder characterised by the congenital absence of the uterus and the upper part of the vagina due to the unsuccessful fusion of the two Müllerian ducts early in the embryological development. MRKH syndrome is estimated to affect 1 in 5000 women and is the second most common cause of primary amenorrhea [1,2].

Patients with MRKH syndrome can be classified into two groups: type I (isolated uterovaginal aplasia) or type II (uterovaginal aplasia with extragenital manifestations). Extragenital anomalies typically include hearing impairment as well as renal, skeletal, cardiac, and ocular malformations [2]. In patients with hypoplasia or aplasia of the vagina, it is possible to create a surgical neovagina [3,4].

The aetiology is not yet fully understood, and although most of the cases are sporadic, familial clustering has also been described, indicating a genetic cause for the disease [5].

The first case of leiomyoma development in patients with MRKH syndrome was described in 1977. Since then, less than 50 cases of leiomyoma have been reported in these patients [6,7].

Our patient was referred to the Radiology department by the Nephrology department for a renal ultrasound follow-up. The ultrasound examination revealed a nodular, well-circumscribed, heterogeneous lesion of 10.6 x 10.8 x 9.9 cm (diameters: transverse, anteroposterior, and craniocaudal) located in the pelvis (Figure 1). The study was completed with a transvaginal ultrasound (Figures 2 and 3) in which only the right ovary was clearly identified. Then, an abdominopelvic CT scan (Figures 4, 5, 6 and 7) was performed, which showed a structure compatible with an ectopic ovary in the right iliac fossa, without clearly identifying the ovaries in the pelvis. Given these findings, the lesion was reported as an ovarian tumour [8–12].

The patient was referred to the Obstetrics and Gynecology department, which performed a successful tumour resection surgery. During the surgery, it was observed that the lesion originated in a rudimentary uterus, which had not been visualised in the previous imaging tests due to its small size. Both ovaries were present. The right ovary was located in the right iliac fossa, and the left ovary was located adjacent to the mass.

The histopathological study of the tumour revealed well-differentiated smooth muscle without atypia or mitotic activity, suggesting leiomyoma of the theoretical rudimentary uterus (Figures 8 and 9) [13].

This case is clinically relevant due to the low prevalence of leiomyomas in patients with MRKH syndrome and the scarcity of published cases on this matter. The significance of the article lies in presenting the possibility of encountering patients with MRKH syndrome who have rudimentary uteri, and who consequently may develop both benign (as in our case) and malignant lesions. Thus, when approaching a similar case, radiologists should take into consideration this differential diagnosis.

All patient data have been completely anonymised throughout the entire manuscript and related files.