A rare case of fallopian tubal choriocarcinoma rupture coexistent with intrauterine pregnancy.

A 32‑year‑old primigravida was admitted to the Department of Obstetrics and Gynecology at The Third Affiliated Hospital of Southern Medical University with a 3‑day history of worsening abdominal pain at 27 weeks and 5 days of gestation. At the onset of symptoms, the abdominal pain was paroxysmal and accompanied by nausea and vomiting. During routine prenatal screening in the first trimester, no pathological ultrasound findings were detected. During the visits at 16, 19, and 21 weeks of gestation, the woman complained of slight abdominal pain, and ultrasound scans indicated a subchorionic hematoma, which was managed with progesterone supplementation therapy. At 24 weeks of gestation, an anomaly scan revealed a hypoechoic mass in the right posterior uterine wall, measuring approximately 91 × 65 × 76 mm, with poorly defined margins and heterogeneous internal echogenicity. Several small cystic areas were seen within the lesion, the largest measuring about 17 × 15 mm, and color Doppler demonstrated scattered internal and peripheral blood flow signals (Fig.  1 A). The mass was interpreted as a uterine myoma, possibly an adenomyoma, with partial cystic degeneration, and no further imaging such as magnetic resonance imaging (MRI) was performed or referral arranged. The patient was managed conservatively and was not hospitalized at that time. Fig. 1 The ultrasound, gross, pathological, and imaging characteristics of the patient’s choriocarcinoma. A Ultrasound image showing a hypoechoic mass in the right posterior uterine wall with heterogeneous echogenicity and internal cystic areas, initially interpreted as a uterine myoma; B Gross specimen of the right fallopian tube showing a ruptured, hemorrhagic intraluminal tumor; C Low-power (H&E) view of choriocarcinoma showing malignant cytotrophoblast cells; D CT image showing multiple lung metastases; E CT image showing a low-density lesion in the right lateral uterine wall, suggesting choriocarcinoma The ultrasound, gross, pathological, and imaging characteristics of the patient’s choriocarcinoma. A Ultrasound image showing a hypoechoic mass in the right posterior uterine wall with heterogeneous echogenicity and internal cystic areas, initially interpreted as a uterine myoma; B Gross specimen of the right fallopian tube showing a ruptured, hemorrhagic intraluminal tumor; C Low-power (H&E) view of choriocarcinoma showing malignant cytotrophoblast cells; D CT image showing multiple lung metastases; E CT image showing a low-density lesion in the right lateral uterine wall, suggesting choriocarcinoma At 27 weeks and 5 days of gestation, the abdominal pain acutely worsened, again accompanied by nausea and vomiting, prompting presentation to the emergency department. On admission, the patient appeared pale and in distress. Her hemoglobin level had dropped to 73 g/L, the white blood cell count was 12.26 × 10⁹/L, and neutrophils accounted for 89.5%. Physical examination revealed abdominal distension, generalized tenderness, rebound pain, and muscular guarding. Fetal heart tones were absent on auscultation, and emergency ultrasound confirmed intrauterine fetal demise as well as a large amount of echogenic fluid in the abdominal cavity, consistent with massive hemoperitoneum. In view of the hemodynamic instability and suspected intra‑abdominal hemorrhage, an emergency laparotomy was performed. During surgery, approximately 1500 mL of blood and clots were evacuated from the peritoneal cavity. Because intrauterine fetal demise had been confirmed prior to laparotomy, the stillborn fetus was rapidly delivered through a uterine incision to decompress the uterus, facilitate exposure of the pelvic cavity, and expedite control of bleeding. Following the rapid delivery of the fetus, the pelvic cavity was carefully explored to identify the source of hemorrhage. An enlarged right uterine horn with a markedly thickened right fallopian tube was noted. The right adnexa was densely adherent to the posterior uterine wall, pelvic wall, and rectum. After meticulous adhesiolysis, a rupture approximately 2 cm in length was identified in the ampulla of the right fallopian tube, with actively bleeding and necrotic tissue protruding from the lumen (Fig.  1 B). Intraoperative frozen section of the tubal lesion indicated a malignant tumor within the fallopian tube. Further exploration revealed malignant‑appearing infiltration of the right ovary and the right posterior uterine wall, together with suspected tumor implants on the omentum. No gross abnormalities were detected in the left adnexa. The total estimated blood loss was 2600 mL, and the adnexal tissues were friable, making hemostasis increasingly difficult. Considering the profound blood loss, prolonged operative time, and high risk of disseminated intravascular coagulation and multiple organ failure if more extensive surgery was attempted, damage control surgery consisting of right adnexectomy and omental biopsy was performed to achieve hemostasis and obtain tissue for definitive diagnosis. The operation was terminated after stabilization of the patient. Postoperative histopathology demonstrated choriocarcinoma involving the myometrium of the right lateral uterine wall, the lumen of the right fallopian tube, the right ovary, and the omentum (Fig.  1 C). The placenta showed no pathological abnormalities. Further postoperative evaluation revealed a markedly elevated serum human chorionic gonadotropin (HCG) level of 314,439 mIU/mL. Contrast‑enhanced computed tomography (CT) of the abdomen and pelvis identified a low‑density lesion in the right lateral uterine wall measuring approximately 47 × 36 mm, without additional pelvic masses apart from postoperative changes, while chest CT demonstrated multiple lung metastases (Fig.  1 D and E) and brain CT showed no abnormalities. The diagnosis was stage IV gestational choriocarcinoma with a FIGO prognostic score of 10. The patient subsequently received multi‑agent chemotherapy with the EMA‑CO regimen (etoposide, methotrexate, actinomycin D, cyclophosphamide, and vincristine). Serum HCG levels had decreased to 209 mIU/mL after the second cycle of chemotherapy. She is currently undergoing regular chemotherapy with close follow‑up, including serial HCG monitoring and periodic imaging to assess treatment response.

Gestational trophoblastic neoplasia (GTN) encompasses a spectrum of malignant tumors derived from trophoblastic tissue, among which choriocarcinoma is a highly aggressive form that can be associated with any type of gestation [ 1 ]. Choriocarcinoma coexisting with normal intrauterine pregnancy is exceedingly rare [ 2 ]. Due to a very low index of suspicion, a correct diagnosis of choriocarcinoma can be delayed in primigravidas. In this report, we present an exceptionally rare case of fallopian tubal choriocarcinoma rupture leading to intrauterine demise and discuss diagnostic and management challenging.

Choriocarcinoma is a relatively rare gynecological malignancy arising from trophoblastic tissue and can be associated with any type of gestation [ 1 , 3 ]. It most commonly occurs following molar pregnancy or after normal intrauterine gestation [ 2 , 4 ]. However, its coexistence with an ongoing normal intrauterine pregnancy is exceedingly rare and carries a high risk of maternal and fetal mortality [ 5 ]. Choriocarcinoma developing during a first pregnancy, as in our case, is even more uncommon and can be particularly challenging to diagnose because of a lower index of suspicion in primigravidas. In this case, choriocarcinoma involved the right lateral uterine wall, the lumen of the right fallopian tube, and the right ovary, with no pathological abnormalities detected in the placenta. Excluding asymptomatic intrauterine and ectopic abortions in women of reproductive age is challenging, complicating the determination of the primary lesion’s origin [ 6 ]. Therefore, the true primary site could not be definitively established in our patient. Two main possibilities should be considered: the lesion may have originated in the uterus during the current pregnancy and subsequently metastasized to the adjacent fallopian tube and ovary; alternatively, it might have arisen from the fallopian tube or ovary, developing from residual trophoblasts of a prior subclinical ectopic gestation. Regardless of the exact primary site, the rapid growth of choriocarcinoma tissue created excessive tension within the right fallopian tube, ultimately leading to tubal rupture, massive intra‑abdominal hemorrhage, impaired placental perfusion, and intrauterine fetal death. In view of these findings, we describe this case as “fallopian tubal choriocarcinoma rupture coexistent with intrauterine pregnancy”, emphasizing the clinically dominant event of tubal rupture rather than a proven tubal primary. From an imaging standpoint, the mass detected at 24 weeks was interpreted as a degenerated uterine myoma based on its location in the posterior uterine wall and the presence of cystic areas. However, in retrospect, several sonographic characteristics could have raised suspicion of a malignant trophoblastic tumor, including the relatively ill‑defined margin, heterogeneous internal echotexture with multiple cystic or necrotic spaces, and the presence of internal as well as peripheral vascularity on Doppler. Typical benign uterine myomas often present as well‑circumscribed, homogeneously hypoechoic lesions with predominantly peripheral blood flow, whereas choriocarcinoma and other malignant uterine masses may show more irregular borders, marked heterogeneity, and prominent internal vascularity. In pregnant patients presenting with a new, rapidly enlarging uterine mass and atypical ultrasound features, additional investigations such as MRI and serial serum HCG assessment should be considered to differentiate benign myoma from choriocarcinoma and to avoid diagnostic delay. Our case highlights that reliance solely on a presumed diagnosis of myoma degeneration in the presence of a large, atypical mass can obscure an underlying malignant process. Clinically, our patient experienced recurrent abdominal pain during the second trimester, initially attributed to subchorionic hematoma and later to presumed myoma degeneration. These nonspecific symptoms, together with the misleading imaging interpretation, contributed to a delay in recognizing the underlying choriocarcinoma until the catastrophic event of tubal rupture and massive intra‑abdominal hemorrhage occurred. Choriocarcinoma often lacks characteristic local symptoms in early stages, and the primary uterine lesion may even regress, so some patients only present with manifestations of metastasis, such as hemoptysis, vaginal bleeding, or neurological symptoms, which can further delay diagnosis. Therefore, in pregnant women with new uterine or adnexal masses, unexplained abdominal pain, or evidence of metastatic disease, choriocarcinoma should be considered in the differential diagnosis even in the absence of a previous pregnancy history or molar gestation. Once diagnosed, choriocarcinoma coexisting with pregnancy should be treated promptly, with treatment plans tailored to gestational age, maternal and fetal condition, and tumor burden [ 7 – 9 ]. Chemotherapy during the first trimester carries a substantial teratogenic risk, and termination of pregnancy is generally recommended before initiating systemic treatment [ 10 ]. In the third trimester, the high likelihood of fetal survival allows for consideration of delivery followed by chemotherapy [ 11 ]. The optimal strategy in the second trimester remains unclear due to the rarity of reported cases; some authors have described successful use of chemotherapy during pregnancy followed by delayed delivery, whereas others have favored early termination followed by systemic therapy [ 12 ]. In our case, the presence of intrauterine fetal demise and life‑threatening maternal hemorrhage dictated an emergency laparotomy with rapid delivery of the fetus, damage‑control surgery, and subsequent multi‑agent chemotherapy once the patient was stabilized. In summary, this case illustrates several important points. First, choriocarcinoma may coexist with an ongoing intrauterine pregnancy and may mimic common benign conditions such as uterine myoma, particularly when presenting as a posterior wall mass with cystic degeneration during pregnancy [ 2 – 4 , 7 ]. Second, atypical sonographic features and rapid progression should prompt further evaluation with MRI and serum HCG, and choriocarcinoma should be included in the differential diagnosis of new uterine or adnexal masses in pregnant women [ 1 , 3 , 6 , 7 , 12 ]. Third, rupture of a tubal or extra‑uterine choriocarcinoma can result in catastrophic intra‑abdominal hemorrhage and fetal loss, requiring timely recognition and a damage‑control surgical approach in unstable patients, followed by standardized multi‑agent chemotherapy [ 1 , 9 ]. Recognizing these features may help clinicians avoid misdiagnosis and improve maternal and fetal outcomes in future similar cases.