Case-presentation
A 32-year-old woman presented in 2019 with secondary subfertility two years after a full-term pregnancy. Her first pregnancy was complicated by a preeclampsia. In October 2016, at 36 weeks and 6 days, she delivered a daughter vaginally after induction of labor. The placenta was retained and removed manually, which was complicated by post-partum hemorrhage. In January 2017 a hysteroscopy was performed due to complaints of irregular vaginal bleeding and suspicion of retained products of pregnancy. A suspected remnant of the placenta was removed hysteroscopically and an intra uterine device (IUD Mirena) was inserted as a contraceptive. The pathology report described normal placental tissue. The IUD was removed in the beginning of 2018 because of a renewed child wish. In March 2019, a hysteroscopy was performed because of secondary subfertility and the suspicion of Asherman’s syndrome. Before the procedure, no abnormalities were seen on transvaginal ultrasound in the myometrium. The endometrial thickness was relatively thin (2.7mm) postovulatory. During the hysteroscopy a small lesion of placenta-like tissue (1cm) was resected. The histologic examination showed linear, superficial linear lesional tissue of 1 cm, with a thickness of 1.2 mm, consisting of hyalinized eosinophilic material with interspersed hyperchromatic, pleomorphic and intermediate type trophoblast. The cells had mainly clear cytoplasm and focally contained eosinophilic cytoplasm. The trophoblastic cells were arranged in cords and small nests. Mitoses and necrosis were not present in the hysterectomy specimen but were seen in the previous histology sample. Some chorionic villi were seen to suggest trophoblast accompanying products of conception. Immunohistochemistry showed that these cells were positive for p63 and showed a Ki-67 or MIB-1 proliferation index of 8-10%. Immunophenotype was that of proliferating intermediate trophoblast. These characteristics were consistent with the diagnosis of APSN.
Following the pathology result, hCG-levels were determined and found to be below the cut-off limits. A CT-scan chest/abdomen and MRI pelvis were performed to exclude an infiltrating, malignant mass, no abnormalities or lesions suspected of metastases were seen. An expectant approach was discussed as the woman wished to conceive again. She was counseled about the association of APSN with PSTT and ETT. Her case was discussed in a national and international multi-disciplinary team. Consensus was to perform three-montly monitoring using serum hCG-levels, transvaginal ultrasound and alternating MRI/hysteroscopy if not pregnant. None of the tests used showed abnormalities during follow-up. The woman achieved two full-term pregnancies two years apart from each other, the pregnancies were uneventful except for a retained placenta in both deliveries resulting in a manual removal of the placenta. Histological examination of both placenta’s did not show any signs of abnormality. The MRI scans performed during the pregnancies were discussed with a specialist in placental MRI scans.
In May 2022, six months after the last pregnancy, a hysterectomy was performed. An atypical, linear and superficial lesion of 1.1 cm was found in the endometrium and pathology results remained consistent for APSN with a Ki-67 proliferation rate of 8-10%. Macroscopically the lesion could not be detected. The woman was discharged from follow-up.