Spontaneous first‐trimester perforation of the uterus following Cesarean scar pregnancy choriocarcinoma

Abstract

Gestational trophoblastic disease (GTD) encompasses a heterogeneous group of lesions with specific clinical features, morphological characteristics and pathogenesis1. The World Health Organization (WHO) modified classification of GTD includes: complete and partial hydatidiform mole, invasive mole, choriocarcinoma, placental site trophoblastic tumor, exaggerated placental site and placental site neoplasms1. Gestational choriocarcinoma is a highly malignant epithelial tumor originating from the trophoblast of any type of gestational event, most often a hydatidiform mole1, and usually arises in the uterine body. Extrauterine choriocarcinoma is a rare entity, with the incidence of primary Fallopian tube choriocarcinoma estimated to be one in every 1.6 million intrauterine pregnancies1. Although symptoms of gestational choriocarcinoma are highly variable, abnormal uterine bleeding is one of the most frequent presentations. Uterine perforation by choriocarcinoma is an unusual event, which has been reported previously2. We report an unusual case in which a patient undergoing evaluation for a suspected late first-trimester ectopic pregnancy was found at laparotomy to have choriocarcinoma perforating through a ruptured previous transverse anterior lower uterine scar. A 34-year-old woman, para 3, presented at 13 + 5 weeks' gestation, according to last menstrual period, complaining of mild pelvic discomfort and mild uterine hemorrhage lasting for 24 h. Her obstetric history was significant for a Cesarean delivery in her first pregnancy followed by successful vaginal birth in her second pregnancy. Her third delivery was by repeat Cesarean section. Her current pregnancy was unplanned and she had not received prenatal care. On evaluation she was in good general health and in no acute distress. She was afebrile with blood pressure of 120/80 mmHg and heart rate of 84 bpm. Her abdomen was soft with mild lower tenderness, yet no signs of peritoneal irritation were present. Bimanual examination was suggestive of an ill-defined enlarged, mildly tender uterus, with no abnormal adnexal findings. Her cervix was long and closed. Laboratory examinations revealed hemoglobin was 11.8 g/dL, hematocrit was 36.3% and white blood cell count was 3.8 × 109 L. Serum electrolytes, creatinine and blood urea nitrogen levels were normal. Serum beta human chorionic gonadotropin level was 76 038 mIU/mL. Transabdominal and transvaginal ultrasound examination (Figure 1a and b) depicted a normal uterus with no evidence of an intrauterine gestation. Both adnexa were normal. No corpus luteum was noted. Anterior to the lower uterine segment, a heterogeneous hemorrhagic soft tissue mass measuring 9 × 8 × 6 cm was noted. An area of discontinuity of the anterior lower uterine segment was observed (Figure 1a). Minimal vascularity was depicted on color Doppler imaging (Figure 1c). With the presumed diagnosis of an ectopic pregnancy of undetermined location, the patient underwent laparoscopy. At laparoscopy, both adnexa were unremarkable with Fallopian tubes appearing normal throughout their lengths. A large mass measuring approximately 10 cm in diameter was noted protruding through a defect in the anterior lower uterine segment. At laparotomy, the mass was removed manually and the defect in the uterine wall was repaired. The resected tissue was tan-brown in color and friable, weighing 65 g in aggregate, and showed extensive necrosis and hemorrhage. Histopathology of the mass confirmed choriocarcinoma. Computed tomography (CT) of the chest revealed multiple scattered nodules of varying sizes (Figure 2). The largest of these nodules in the lower lobe of the right lung measured approximately 1.8 cm in the long axis and the largest in the left lower lung lobe measured approximately 1.7 cm in the long axis. The lung nodules were considered consistent with intrathoracic metastatic disease. Cranial CT showed no evidence of metastatic disease. The patient was counseled extensively regarding her diagnosis of high-risk metastatic choriocarcinoma and multiagent chemotherapy was recommended. Notwithstanding, the patient declined further treatment, discharged herself against medical advice and, despite considerable efforts, could not be located. Cesarean scar pregnancy (CSP) (a gestation implanting in the area of the incision of a previous Cesarean section) is a recently recognized clinical entity in which the placenta invades the myometrium pathologically (an early form of morbidly adherent placenta, placenta accreta or percreta)3-8. The progressive and pathological invasion of the placenta is life-threatening and may lead to severe obstetric complications, including massive hemorrhage, uterine dehiscence/rupture and premature delivery at any time during pregnancy. Morbidly adherent placenta is the principal indication for peripartum hysterectomy and associated surgical injuries7. The prevalence of CSP has been estimated at 1 in 800 to 1 in 2500 of all Cesarean deliveries7. Detailed diagnostic sonographic criteria for this life-threatening complication of pregnancy have been described by Timor-Tritsch et al.7. They reported spontaneous rupture of the uterus in 15/47 (32%) cases, most being silent rupture, followed by bleeding, shock and hemoperitonem. The only previous case of CSP choriocarcinoma was reported in 2014 by Qian and Zhu9. A systematic search (PubMed and MEDLINE) of the English medical literature published between 1966 and 2016, utilizing the search terms ‘choriocarcinoma’, ‘Cesarean scar pregnancy’ and ‘uterine perforation’, confirmed that our case is the first report of perforation of the uterus by CSP choriocarcinoma. This case confirms the observation of Timor-Tritsch et al., pertaining to an increased likelihood of (often silent) uterine rupture associated with CSP7. Our case adds yet another previously unreported etiology of such rupture – CSP choriocarcinoma. D. M. Sherer*†, M. Dalloul†, Y. Cho‡, S. R. Mylvaganam‡, I. Adeyemo†, H. L. Zinn§ and O. Abulafia‡ †Department of Obstetrics and Gynecology, Divisions of Maternal Fetal Medicine, State University of New York (SUNY), Downstate Medical Center, 450 Clarkson Avenue, Box 24, Brooklyn, New York, NY, USA; ‡Gynecologic Oncology, State University of New York (SUNY), Downstate Medical Center, Brooklyn, New York, NY, USA; §Department of Radiology, State University of New York (SUNY), Downstate Medical Center, Brooklyn, New York, NY, USA *Correspondence. (e-mail: [email protected])