Ovarian adenomyoma: a case report

Abstract

Introduction

Ovarian adenomyoma is a rare gynecological tumor with a high misdiagnosis rate, leading many patients to undergo unnecessary surgeries that may affect fertility. Menstrual abdominal pain is the most common symptom, and auxiliary examinations often cannot clarify its nature. It often relies on intraoperative diagnosis, and surgical resection can achieve good therapeutic effects.

Case presentation

A 50-year-old woman presented with lower abdominal pain during her menstrual period for the past two months. She had a previous medical history of uterine adenomyomectomy, ovarian cystectomy, and a cesarean section. Ultrasound revealed a 5.7 × 3.8 × 4.3 cm mass on the posterior wall of the uterus, a 9.9 × 5.6 × 8.2 cm hypoechoic mass in the right posterior part of the uterus, and a 2.8 × 2.2 × 2.7 cm anechoic mass in the left ovary. CA125 (Carbohydrate antigen 125) 191.80U/ml (0–30). MRI (magnetic resonance imaging) imaging confirmed a 7.9 × 6.2 × 7.2 cm fibroid on the right posterior wall of the uterus. Consider partial degeneration of multiple uterine fibroids and benign cystic degeneration in the lower left abdomen. Surgical resection was performed smoothly, and the diagnosis was confirmed by postoperative pathology.

Conclusion

Ovarian adenomyoma is a rare benign gynecologic tumour with a high rate of misdiagnosis. When a patient presents with recent lower abdominal pain or dysmenorrhea, a history of endometriosis or myomectomy, and MRI findings showing irregular bleeding patterns in a pelvic mass, the possibility of extrauterine adenomyosis should be considered. Minimally invasive treatment options, such as single-port laparoscopy or vaginal dissection, may offer advantages, but caution should be exercised due to the potential for malignant tumors. Preserving fertility is something worth exploring. We hope to provide warnings to more gynaecologists and reduce misdiagnosis and unnecessary treatment.

Introduction

The prevalence of adenomyosis ranges from 5–70% [1]. This condition can develop into localized nodules or masses, known as adenomyomas. The most common locations for extrauterine adenomyomas are the pararectal space, ovaries, and broad ligament [2]. However, ovarian adenomyomas are extremely rare. As far as we know, only 11 cases of ovarian adenomyoma have been reported, with only one documented case in China [2]. The first case was reported by McDougal in 1986 [3], and all cases were diagnosed through postoperative pathology. Notably, five women of reproductive age underwent unnecessary hysterectomy due to the lack of a precise preoperative diagnosis. Based on existing reports, abdominal and pelvic pain, along with menstrual abnormalities, are the most common clinical manifestations of ovarian adenomyoma [4]. Additional symptoms, such as abnormal vaginal bleeding and infertility, have also been noted [2]. Given the varying sizes and locations of adenomyomas, patients may also experience symptoms like rectal compression, leading to altered bowel habits or stool characteristics [5]. The compression from large pelvic and extrauterine adenomyomas can also affect urination [6]. The lack of specificity in these clinical features often leads to unnecessary treatments; this article discusses the case of a woman who was admitted to the hospital for 2 months of abdominal pain due to menstruation and was diagnosed with ovarian adenomyoma after surgery. We also conducted a literature review discussing the pathogenesis, MRI characteristics, minimally invasive treatment approaches, and fertility preservation related to ovarian adenomas, which holds significant implications for the future treatment of the disease. This work follows the SCARE 2023 guidelines to ensure quality reporting [7].

Case presentation

A 50-year-old patient was hospitalized due to lower abdominal pain during menstruation for 2 months. Seventeen years ago, the patient underwent a laparoscope uterine adenomyomectomy to address menorrhagia and urinary frequency, during which a 3 cm right ovarian follicular cyst was also removed. Postoperatively, her menstruation was normal. She had a cesarean Sect. 8 years ago and has no history of dysmenorrhea. On physical examination, the patient weighed 58 kg, with a BMI (Body mass index) of 22.7. The uterus was enlarged to the size of a uterus at 40 days of pregnancy. A hard, solid mass (approximately 9 cm) was palpable behind the uterus, with normal mobility and no tenderness. Ultrasonography revealed a 5.7 × 3.8 × 4.3-cm mixed hypoechoic and anechoic mass on the posterior wall of the uterus, with a 9.9 × 5.6 × 8.2-cm hypoechoic area in the right posterior part of the uterus. The right ovary was not visible, and an anechoic area, measuring 2.8 × 2.2 × 2.7 cm with good internal translucency, was detected in the left ovary. MRI revealed a space-occupying lesion in the right posterior part of the uterus, measuring 7.9 cm × 6.2 cm × 7.2 cm, closely related to the adjacent right uterine wall. CA125 191.80 U/mL. Preoperative diagnoses included multiple uterine fibroids and a left ovarian cyst.

Considering the patient’s lack of desire for fertility and the possibility of malignant tumours, a total hysterectomy and right adnexectomy were performed. Intraoperatively, the right ovary appeared enlarged and adherent to the surrounding tissues, and a smooth oval tumour with a diameter of about 10 cm was observed internally. A grey-white oval hard mass with a diameter of 10 cm was seen on the section, with a clear boundary between the surrounding tissue. The right fallopian tube is elongated, and the left ovary is enlarged, demonstrating a cyst approximately 3.0 cm in diameter with a thin wall and clear fluid. The left fallopian tube is unremarkable. A grayish-red hard mass of approximately 1.0 cm in diameter was observed in the sacral ligament on the left side. Postoperative pathology confirmed adenomyosis of the uterus, an adenomyoma of the right ovary, a mass in the left uterosacral ligament, and endometriosis. The patient was followed up for one month after surgery without any abnormalities (See Figs. 1, 2 and 3).

Fig. 1

A–D T1WI, the mass showed equal signal intensity, with multiple small round internal areas of high signal intensity (A); T2WI, the mass demonstrated primarily a slightly high signal intensity, with multiple small internal round areas of high signal intensity and patchy low signal intensity (B); Lipid suppression on T1WI showed a mixed signal and scattered small round high signal and patchy low signal areas (C); T1WI enhancement shows uneven moderate enhancement (D)

Fig. 2

The pathological image is HE × 100, with red arrows indicating glands and blue arrows indicating fibrous tissue

Fig. 3

Postoperative ultrasound of the uterus and right ovary showed no abnormal echogenicity

Discussion

Among published cases of ovarian adenomyoma, the majority of patients (81.8%, 9/11) were women of childbearing age. Lower abdominal pain or menstrual lower abdominal pain was reported in 72.7% (8/11) of cases, and excessive menstrual flow in 36.4% (4/11). Other symptoms included constipation, primary amenorrhea, palpable masses, dyspareunia, and infertility [2, 4, 8]. Additionally, 36.4% (4/11) had a history of endometriosis or uterine fibroids. Elevated levels of CA125 and CA19-9 (Carbohydrate antigen 199) were observed in two cases (18.2%, 2/11), which returned to normal after surgery. Ultrasound examinations in ten patients revealed solid or complex cystic masses, and four patients underwent MRI, with one displaying multiple hyperintense signals on T1-weighted images and hypointense signals on T2-weighted images. At the same time, another showed low signals on both T1 and T2-weighted images, which were not given due attention. Despite these findings, unnecessary hysterectomies were performed in 45.5% (5/11) of childbearing-age women. Only one case showed malignant transformation [9], while most patients recovered well postoperatively. Limited follow-up data suggest no recurrence in two patients.

The pathogenesis of ovarian adenomyoma remains unclear. Two main theories have been proposed: uterine or Müllerian fusion defects and subluminal stromal transformation [9]. The Müllerian fusion defect theory links the anomaly to developmental issues in the reproductive tract [10]. Among the 35 cases of ectopic adenomyoma analyzed by Viola et al. [11], 22 cases were considered to have developed due to abnormalities in reproductive tract formation. Alternatively, subluminal stroma, derived from the urogenital ridge, may undergo metaplasia and differentiate into smooth muscle cells, as initially described by Cozzuto in 1981 [12]. This patient has a history of uterine adenomyoma resection and endometriosis, and the occurrence may be related to smooth muscle metaplasia within the endometriotic lesions or cellular implantation following the resection of the uterine adenomyoma.

Some were initially considered malignant ovarian tumours before surgery [9]. Therefore, a preoperative MRI is necessary. Typical MRI findings for ovarian adenomyosis include low signal intensity on T2-weighted images and areas of high signal intensity on fat-suppressed T1-weighted images, indicative of internal bleeding. Pathology reveals the presence of endometrial glands, specialized endometrial stroma, and well-formed smooth muscle bundles [13]. The patient’s pathological images further confirm this, showing the presence of glands and smooth muscle, with SMA (Smooth muscle actin) staining positive, which supports a smooth muscle origin for the lesion and confirms the diagnosis of adenomyoma. Previously, the tumour was described as a well-defined oval nodular mass, often surrounded by a thick muscle wall and a cavity containing chocolate-like brown, bloody, serous, and mucinous fluids. Blood clots are commonly observed within the masses. CA125 is an important tumour marker for early screening of ovarian cancer and can also show varying degrees of elevation in benign gynaecological diseases [2]. Elevated CA125 levels have been reported in broad ligament and salpingeal adenomyomas [14, 15], and elevated CA199 levels have been noted in ampullary adenomyomas [16]. Although the CA125 level in this patient was higher than the normal level, it is not specific to ovarian adenomyosis. Differentiation among endometriosis, ovarian fibromas, and ovarian thecomas is essential (See Table 1).

Table 1 Key differential points

Due to the significant impact of unnecessary hysterectomy on patients’ fertility, preserving reproductive function and employing minimally invasive surgery are critical in managing ovarian adenomyoma. Techniques such as single-port laparoscopy or transvaginal tumor resection promote faster recovery with minimal scarring. It is well established that the administration of GnRH agonists (gonadotropin-releasing hormone agonists) can delay the progression of adenomyosis; therefore, exploring the potential application of GnRH agonists to delay disease progression in patients with ovarian adenomyosis who do not require surgery or to prevent recurrence in women of reproductive age postoperatively, is warranted [25].

In summary, ovarian adenomyoma is a rare and challenging gynecological. Preoperative diagnosis is difficult and often relies on postoperative pathology. Minimally invasive surgical approaches and fertility preservation strategies warrant further investigation. If there is recent lower abdominal pain or dysmenorrhea, a history of endometriosis or myomectomy, and MRI shows signs of multiple bleeding areas in the pelvic tumour, the possibility of extrauterine adenomyosis should be considered.