Ruptured ectopic molar pregnancy and ruptured uterine fibroid: a challenging rare diagnosis

Abstract

Although rare and unusual occurrences, a ruptured ectopic molar pregnancy (MP) and a ruptured uterine fibroid can lead to significant maternal morbidity and mortality. We present a unique case of these complications developing concurrently—resulting in the haemodynamic compromise of an otherwise healthy young female patient. The patient underwent a diagnostic laparoscopy which converted into a laparotomy, salpingectomy and myomectomy. Comprehensive histopathology confirmed the diagnosis of a ruptured ectopic complete MP and ruptured uterine fibroid. The patient recovered quickly within days. Prompt definitive management, conclusive histopathology and adequate follow-up were the hallmarks of this singular case. These key factors lead to the rare diagnosis of ruptured ectopic MP and uterine fibroid, prevention of adverse outcomes and provision of comprehensive patient care.

Background

The diagnosis and treatment of a simultaneous ruptured tubal ectopic molar pregnancy (MP) and a ruptured uterine fibroid are examined in this case report.

An ectopic pregnancy (EP) arises from the implantation of a fertilised ovum anywhere outside the uterine cavity, with at least 95% in the fallopian tube. Ectopic pregnancies have an incidence of 1–2 events in every 100 pregnancies. All EPs result in a non-viable pregnancy and require management whether by expectant, medical or surgical management. Importantly, ruptured ectopic pregnancies occur in approximately 18% of all ectopic pregnancies and cause almost 6% of maternal deaths.^1–3

In MPs, the placental tissue grows abnormally either in the absence of a viable fertilised ovum (complete hydatidiform mole) or presence of abnormally fertilised ovum (partial hydatidiform). Its incidence is even lower with 1–2 events in every 1000 pregnancies.^{4 5} Gestational trophoblastic neoplasia (GTN) may develop in up to 25% of cases of complete hydatidiform mole if not treated appropriately; hence, the identification and complete treatment of a MP has significant consequences for the patient.⁶

The incidence of ectopic MP is only 1 in 20 000 to 1 00 000 with few case reports published in medical literature.⁶

Uterine fibroids (also known as leiomyomas) are common benign smooth muscle tumours with an incidence of up to 70% in Caucasian women. Most women are asymptomatic; however, the tumours are usually oestrogen and progesterone receptor positive and can be complicated by haemorrhage, infarction and hyalinisation during pregnancy (so called red degeneration and apoplectic change). Rarely, acute complications such as uterine fibroid rupture can cause significant morbidity and even mortality. There are less than 200 case reports of spontaneous uterine fibroid rupture in existing literature.^7–11

This case report is exceptional in that the patient concurrently had both rare life-threatening events—a ruptured ectopic MP and a ruptured uterine fibroid.

Case presentation

A primigravid woman in her 30s presented to the emergency department of a peripheral metropolitan site with thick brown vaginal discharge associated with a 12-hour history of right lower abdominal cramping and pink coloured light vaginal discharge. She estimated her pregnancy to be 4 weeks gestation based on her last menstrual period and positive home urine pregnancy test. She was otherwise healthy with no relevant medical history.

On examination, she was haemodynamic stable, with a palpable mass in the infraumbilical region associated with mild discomfort on examination. A bedside ultrasound scan (USS) by the obstetrics and gynaecology registrar failed to demonstrate an intrauterine pregnancy, but showed a large cystic structure on the left ovary, no free fluid in the pouch of Douglas and closed cervix. With a high beta-human chorionic gonadotropin hormone (bhCG) level of 15 156 IU/mL, a diagnosis of pregnancy of unknown location was made. The patient was transferred to a tertiary hospital for formal imaging and ongoing management.

Investigations

Additional investigations on presentation showed white cell count 14.6×10⁹/L, neutrophils 12.6×10⁹/L and haemoglobin (Hb) 125 g/L. Urinalysis was positive for leucocytes.

A formal transvaginal USS showed an empty uterus, right adnexal mass adjacent to the right ovary and further well-circumscribed mass adjacent to the right aspect of the uterus. The first adnexal mass measured 3 cm, looked heterogenous with peripheral vascularity and was separate to ovary. The second mass measured 11 cm and looked anechoic with thick walled vascularity suggestive of placental mass. It was also separate from uterus and ovary. While awaiting a diagnostic laparoscopy, the patient became haemodynamically unstable and the surgical category was upgraded.

A cancer screen showed an elevated cancer antigen 125 (CA125) at 367 kU/L but normal cancer antigen 19.9 (CA19.9), carcinoembryonic antigen (CEA) and alpha fetoprotein (AFP).

Differential diagnosis

Primary differentials for the patient’s presentation and USS results include pregnancy of unknown location, EP, threatened or incomplete miscarriage and ovarian torsion. Less likely differentials include heterotopic pregnancy and MP. Differentials for the right adnexal masses include corpus luteal cyst, ovarian or endometrial carcinoma, uterine sarcoma or leiomyoma and ovarian fibroma. After the development of haemodynamic compromise, a ruptured EP with incidental finding of large unidentified right adnexal mass was the presumed diagnosis.

Treatment

Perioperatively, the acute Hb drop to 107 g/L from 123 g/L prompted cross-matching 4u of packed red blood cells (pRBC) to commence a massive transfusion protocol.

An emergency diagnostic laparoscopy was performed with direct optical entry at Palmer’s point. The procedure identified a massive ruptured fundal fibroid extending past the umbilicus and a ruptured ectopic with a considerable haemoperitoneum of 3.5 L.

At this time, the operation converted to a midline laparotomy and a right salpingectomy swiftly performed. A 12 cm fundal intramural fibroid with a solid cystic component was observed that had ruptured through the serosal aspect with large flap draining clear fluid. A myomectomy was performed with blunt dissection and cautery. The fibroid was shelled out bluntly through the site of spontaneous rupture without breaching the uterine cavity. To repair the anatomy, the serosa was trimmed and defect closed with 1 vicryl in layers. The serosal aspect was closed with 2-0 monocryl herringbone sutures. The fundal defect was oversewn with vicryl 1-0 and 2-0 for ongoing bleeding and Surgicel placed over the uterus. Haemostasis was confirmed after copious wash of the abdominal quadrants. A 10F Bellovac drain was inserted into the pelvis at the conclusion of the surgery.

Intraoperatively, her Hb dropped further to 68 g/L with low fibrinogen associated with persistent haemodynamic instability. Units of pRBC and cryopercipitate were appropriately transfused. The patient had a total estimated blood loss volume of 3.7 L.

Outcome and follow-up

Postoperatively, the patient recovered uneventfully on the wards with the exception of requiring a further 2u pRBC and an iron infusion as she experienced symptomatic anaemia with low Hb. The bhCG dropped as expected to 4871 IU/mL on postoperative day 0. Her Bellovac drain was removed on postoperative day 2 and she was discharged on postoperative day 5. On postoperative day 11, her bhCG continued downtrending to 140 IU/mL.

Macroscopic examination confirmed distension of the fallopian tube by an EP (figure 1A) and fragments of disrupted and haemorrhagic leiomyoma (figure 1B, C). Microscopically, the EP was composed of a complete hydatidiform mole (figure 2) with exuberant proliferation of villous and extravillous trophoblast, stromal karyorrhectic debris and expanded basophilic mesenchyme. Immunohistochemistry showed diagnostic loss of p57 staining within the cytotrophoblast and villous stromal cells. The excessive bhCG level for gestational age (bhCG ~15 000 IU/mL at 3 weeks gestation dropping to ~4000 IU/mL postoperative) was also suggestive of very early MP.

Figure 1.

(A) Right fallopian tube (70 mm) with dilated ampulla (25 mm). (B) Benign leiomyoma within uterine wall and uterine serosa with focal areas of haemorrhage. It measured 75×70×30 mm and weighed 90 g. (C) Cut surfaces of the benign leiomyoma.

Figure 2.

Complete hydatidiform mole with expanded blue mesenchyme and proliferating atypical trophoblast (H&E stain at ×100 magnification).

The gynaeoncology team continued the management of her MP. She completed her bhCG tracking for complete MPs as per local protocols with no need for additional therapy. The results of further investigations as per the gynaeoncology team observed no signs of metastatic disease (figure 3).

Figure 3.

A clear chest X-ray with no signs of bony metastases (A, B). A CT scan of the chest–abdomen–pelvis reporting no adenopathy or metastatic disease with right-sided heterogenous myometrium likely postoperative in nature (C, D).

Discussion

This is the first reported case of concurrent ruptured ectopic MP and ruptured uterine fibroid.

Preoperative USS imaging could not definitively identify the right adnexal masses observed in our patient. Routinely, USS identifies less than 50% of MPs.¹² It was only through diagnostic laparoscopy that the answer emerged and prompted decisive surgical treatment.

Each of the individual diagnoses—ruptured EP, MP and ruptured uterine fibroid—hold long-term consequences for a patient with no prior risk factors for any of these conditions apart from her age. The patient now has a 10%–15% risk of future EP and a 1.67% risk of repeat MP—both approximately tenfold of the baseline risks of EP and MP.^{13 14} There is up to a 47% rate of uterine fibroid recurrence especially in the context of her age and reproductive stage of life.^{15 16} Despite these increased risks, the patient can still expect to have a healthy spontaneous intrauterine pregnancy, especially after her myomectomy.^17–19

After primary surgical intervention and identification of the complete MP on histopathology, monitoring for GTN is important. If disease persistence or malignancy such as choriocarcinoma is identified, the next stage of treatment may include chemotherapy. Treatment of MPs is typically with curative intent with excellent responses to adjuvant treatment.²⁰

This case report adds to the existing limited body of scientific literature around these conditions. It reaffirms that histopathology should be sent post salpingectomy for EP.^{12 21} The patient’s management during her hospital admission exemplifies the importance of serial clinical review, diagnostic laparoscopy and histology in delivering high-quality medical care and preventing long-term adverse outcomes from potential missed diagnoses.

Patient’s perspective.

I am doing very well these days. I am very thankful to the whole team who operated on me that night and provided care and follow-up afterwards.

It was a life-threatening experience as I had never been hospitalised before. Being an international student, living far away from family and, on top of that, having my husband who could not visit me in the hospital due to COVID-19 restrictions was really a tough time for me. But, I am very thankful to all the nurses and doctors who worked hard. I cannot express enough how thankful I am.

Learning points.

• Even through comprehensive work up from blood tests to imaging, preoperative diagnoses of certain gynaecological issues such as ectopic molar pregnancy (MP) and ruptured uterine fibroid are difficult to confirm.

• Complex and potentially critically unwell patients are best managed in a well-resourced tertiary healthcare facility to receive timely intervention.

• Complete or partial MPs require thorough assessment in order to determine ongoing management requirements to prevent development of choriocarcinoma or an invasive gestational trophoblastic neoplasia and rule out metastases.

Ethics statements

Patient consent for publication

Consent obtained directly from patient(s).