Integrating ultrasound findings and extreme CA-125 elevation in the diagnosis of spontaneous endometrioma rupture: a case report

A 27-year-old woman presented to the labor and delivery unit with acute abdominal pain that had persisted for 1 day. She had a 2-year history of dysmenorrhea secondary to endometriosis. Previously, she had been treated with leuprolide for 6 months, followed by dienogest for 1 year, which reduced her symptoms. However, she subsequently discontinued therapy. Currently, she reported abdominal pain coincided with the start of menses. She denied urinary or bowel symptoms such as dysuria or dyschezia. On admission, her vital signs were: blood pressure 124/72 mmHg, heart rate 105 beats/min, respiratory rate 18 breaths/min, temperature 36.8 0 C, oxygen saturation 99%, and visual analogue scale pain score of 10. Physical examination revealed diffused abdominal tenderness with positive guarding. A mobile, cystic mass, extending from the symphysis to midway toward umbilicus, was palpable. External gynecologic exam showed normal vulva and urethra. On rectal examination, the rectum was intact and the uterus was anteflexed. A left adnexal mass measuring approximately 10 cm was palpated, while the right adnexa was unremarkable; the parametrium was smooth. Ultrasonography demonstrated a symmetrical, anteflexed uterus measuring 65 × 38 × 44 mm (volume 57.2 cm3), with homogenous myometrium and an endometrial thickness of 5.8 mm. The endocervix and cervix appeared normal. The right ovary measured 34 × 34 × 15 mm (volume 6.3 cm 3 ). The left ovary measured 102 × 88 × 88 mm (volume 410.7 cm 3 ) and contained a unilocular cyst mass with internal echoes with a ground glass appearance, consistent with endometrioma. The cyst wall was irregular, with features of collapse. Free fluid was present in the abdominal cavity with an echogenicity similar to the cyst content (Fig. 1 ). The sliding sign was negative. Both kidneys were normal without pelvicalyceal dilatation. The findings corresponded to O-RADS category 3. These clinical findings were summarised in Table 1 . Figure 1. Unilocular cyst mass with internal echoes with ground glass appearance, consistent with endometrioma. The cyst wall was irregular, with features of collapse. Free fluid was present in the abdominal cavity with echogenicity similar to the cyst content. Table 1 Summary findings. History taking Physical examination Laboratory Ultrasound History of endometrioma A mobile, cystic mass, extending from the symphysis to midway toward umbilicus CA-125 5315 U/ml The cyst wall was irregular, with features of collapse. Free fluid was present in the abdominal cavity with an echogenicity similar to the cyst content Improvement of symptoms after administration of leuprolide or dienogest C-reactive protein 96.8 mg/L procalcitonin 1 ng/ml Unilocular cyst mass with internal echoes with ground glass appearance, consistent with endometrioma. The cyst wall was irregular, with features of collapse. Free fluid was present in the abdominal cavity with echogenicity similar to the cyst content. Summary findings. Laboratory investigations revealed: CA-125 5315 U/ml, C-reactive protein 96.8 mg/L, procalcitonin 1 ng/ml, anti-Müllerian hormone 0.54 ng/ml, hemoglobin 11.3 g/dl, hematocrit 33.7%, Mean Corpuscular Volume 80.2 fL, Mean Corpuscular Hemoglobin 26.9 pg, Mean Corpuscular Hemoglobin Concentration 33.5 g/dL, leukocytes 10 910/μL (neutrophils 81.6%; lymphocytes 13.4%), and platelets 228 000/μL. Coagulation profile showed Prothrombin Time 1× control and Activated Partial Thromboplastin Time 1.1× control. Electrolytes were sodium 136 mEq/L, potassium 3.5 mEq/L, and chloride 106.7 mEq/L. Renal function showed blood urea nitrogen 19.3 mg/dL, creatinine 0.4 mg/dL, and eGFR 139.9 mL/in/1.72 m 2 . Liver function was within normal limits (Alanine Transaminase 21 U/L, Aspartate Amino-transferase15 U/L). Urinalysis was unremarkable. Intraoperatively, approximately 1000 mL of chocolate-colored fluid was found within the peritoneal cavity (Fig. 2 ). A 10-cm cyst was identified in the left ovary, adherent to the posterior uterine corpus and rectum. The surgical procedure included decompression of the cyst, adhesiolysis of the cyst from the posterior uterine wall and rectum, followed by cystectomy and peritoneal lavage. According to the Enzian classification, the lesion was assessed as O3/0 C3, and as per the American Society for Reproductive Medicine, this was consistent with stage III–IV endometriosis. Patient was admitted for 3 days. Figure 2. Chocolate fluid filling the peritoneal cavity. Left ovary adhered to the posterior uterine corpus and rectum. Performing left ovarian cystectomy. Chocolate fluid filling the peritoneal cavity. Left ovary adhered to the posterior uterine corpus and rectum. Performing left ovarian cystectomy. Histopathological examination revealed a cystic lining with cuboidal epithelium, lymphocytes, plasma cells, hemosiderin-laden macrophages, congested vessels, hyperemia, and endometrial glandular and stromal cells (Fig. 3 ), confirming the diagnosis of endometriosis. Figure 3. Histopathology feature of endometriosis: lymphocyte, plasma cell, hemosiderophage cell, and glandular and stromal epithelial cells. Histopathology feature of endometriosis: lymphocyte, plasma cell, hemosiderophage cell, and glandular and stromal epithelial cells. Postoperatively, the patient was administered leuprolide for 3 months in our hospital. Depot medroxyprogesterone acetate injections was given every 3 months as maintenance therapy by the original operating surgeon. After a 1-year follow-up, patient was without reported pelvic pain and repeated ultrasound imaging showed no recurrence of an endometrioma.

Endometriosis is the growth of ectopic endometrium outside of the uterus. Endometriosis can cause dysmenorrhea, infertility, and chronic pelvic pain. It affects 10% reproductive women[ 1 ]. It is hypothesized that endometriosis is the result of retrograde menstruation, immunity dysregulation, and endocrine disruption. The retrograde menstruation provides stromal and epithelial cells of endometrium to be present in the pelvic cavity. In healthy women, immune system acted as a scavenger. However, in endometriosis patient immune system such as neutrophil and macrophage releases cytokines and chemokines to provides proliferation, angiogenesis, and anti-apoptosis of ectopic endometrial. In order to grow, ectopic endometrium needs estrogen circulation; however, these particular cells also synthesized estrogen de novo. These microenvironments may lead to progression and severity of the disease. The other hypotheses are coelomic metaplasia and benign metastasis to elucidate the endometriosis growth in women without uterus and outside pelvic cavity such as pleura[ 2 ]. Endometriosis manifests as superficial endometriosis (70%–80%), endometriosis cyst (17%–44%) and deep infiltrated endometriosis (5%–12%)[ 3 ]. HIGHLIGHTS Endometrioma can manifest as an acute abdominal pain that requires emergency surgery Irregular surface of cyst and low level echogenicity are the marker for ovarian endometriosis rupture Extremely high CA-125 may provide valuable diagnosis of rupture endometrioma Chocolate fluid originated from endometrioma may cause chemical peritonitis Endometrioma can manifest as an acute abdominal pain that requires emergency surgery Irregular surface of cyst and low level echogenicity are the marker for ovarian endometriosis rupture Extremely high CA-125 may provide valuable diagnosis of rupture endometrioma Chocolate fluid originated from endometrioma may cause chemical peritonitis Endometrioma can manifest as an acute abdominal pain that requires emergency surgery Irregular surface of cyst and low level echogenicity are the marker for ovarian endometriosis rupture Extremely high CA-125 may provide valuable diagnosis of rupture endometrioma Chocolate fluid originated from endometrioma may cause chemical peritonitis Endometrioma or endometriosis of the ovary occurs due to transplantation of the endometrium at the ovarian cortex. The invagination of the lesion can produce chocolate-like fluid fill cyst consisting of degraded blood products. Spontaneous rupture occurs in 3% cases and can lead to diffuse peritonitis[ 4 ]. Therefore, the objective of this case report is to illustrate the management of a ruptured endometrioma manifests as diffuse peritonitis. The work has been reported in line with the SCARE criteria[ 5 ].

The acute abdomen in this patient was caused by diffuse peritonitis secondary to rupture of an endometrioma. The spilled cyst fluid, characterized by a chocolate-like appearance, contained free radicals that damages mesothelial cells of the peritoneum, triggering immune cell recruitment and amplifying the inflammatory response[ 6 ]. Regardless of the etiology, the clinical presentation of an acute abdomen represents a surgical emergency that requires prompt intervention[ 7 ]. Pelvic ultrasonography demonstrated a unilocular cyst with internal echoes with a ground-glass appearance, consistent with endometrioma[ 8 ]. The cyst content typically consists of degraded hemoglobin, hemorrhage particles, and proteinaceous debris with a viscous consistency, producing the echogenic internal pattern observed on ultrasound. The findings of an irregular cyst wall, with wall collapse, free peritoneal fluid, and peritoneal debris were indicative of cyst rupture[ 9 ]. CA-125 is a high-molecular weight glycoprotein (MUC16) produced by coelomic epithelial derivatives such as the endometrium, fallopian tube, pleura, peritoneum, and pericardium. Elevated serum CA-125 is commonly used as biomarker for diagnosis of initial presentation and recurrence of epithelial ovarian cancer, although it can be elevated in benign conditions in reproductive-aged individuals, such as with endometriosis. In this case, markedly elevated CA-125 levels were attributed to rupture of a large endometrioma causing diffuse peritonitis[ 10 ]. Foote et al reported the CA-125 level after spontaneous rupture of an endometrioma to be in the mid-3000s, which is lower in the present case[ 11 ]. However, Rani et al reported that the CA-125 level is above 9000s, which is higher than our case[ 12 ]. Intraoperative findings revealed chocolate-colored fluid filling the peritoneal cavity. The rupture site originated from adhesion between the left ovarian cyst, the posterior uterine wall, and the left fallopian tube. The longstanding inflammation caused by retrograde menstruating caused adhesions and areas of ovarian tissue thinning, creating conditions that promote the development of adhesions, which then can be prone to rupture if adhesions are stressed. The chosen surgical management was an open left ovarian cystectomy performed to preserve future fertility. However, ovarian cystectomy carries the drawback of reducing ovarian reserve due to the removal of ovarian tissue despite all attempts to preserve as much of the ovary as possible during the cystectomy. For more superficial implants of endometriosis, CO2 laser vaporization can ablate ectopic endometrial tissue, thus preserving more ovarian follicles [ 13 , 14 ] . Recurrence of endometriosis occurs in approximately 10%–20% of patients undergoing cystectomy within 18 months[ 13 ]. Therefore, long-term medical therapy is required to suppress residual microscopic lesions and prevent new growth. In this case, postoperative management included a gonadotropin-releasing hormone agonist, leuprolide, administered for the first 3 months, followed by depot medroxyprogesterone acetate injections every 3 months as progestin therapy[ 14 ]. Kolovos et al proposed a diagnostic algorithm for patients with suspected rupture endometrioma. Foote el al and Rani et al relied on CT imaging to establish the diagnosis ruptured endometrioma [ 11 , 12 ] . In contrast, our case demonstrates that ultrasound can also be effectively utilized to identify this condition. The algorithm further advises that ruptured cyst measuring more than 5 cm should be managed with laparoscopy cystectomy and peritoneal lavage[ 15 ]. However, in our case, a laparotomy approach was undertaken. This management strategy may offer a more cost-effective alternative in comparable clinical scenarios.

Spontaneous rupture of endometrioma presenting with diffuse peritonitis is a rare clinical entity. Prompt diagnosis requires the integration of ultrasound findings with serum CA-125 levels. Given that endometriosis is a chronic condition, long-term medical management and careful monitoring are essential.