Can immunohistochemistry improve the pathological diagnosis of placenta accreta spectrum (PAS) disorders?

PURPOSE: The term of placenta accreta spectrum (PAS) disorder includes all grades of abnormal placentation. It is crucial for pathologist provide standardized diagnostic assessment to evaluate the outcome of management strategies. Moreover, a correct and safe diagnosis is useful in the medico-legal field when it becomes difficult for the gynecologist to demonstrate the suitability and legitimacy of demolitive treatment. The purposes of our study were: (1) to assess histopathologic features according to the recent guidelines; (2) to determine if immunohistochemistry can be useful to identify extravillous trophoblast (EVT) and to measure the depth of infiltration into the myometrium to improve the diagnosis of PAS. METHODS: The retrospective study was conducted on 30 cases of gravid hysterectomy with histopathologic diagnosis of PAS. To identify the depth of EVT, immunohistochemical stainings were performed using anti MNF116 (cytokeratins 5, 6, 8, 17, 19), actin-SM, HPL (Human Placental Lactogen), vimentin and GATA3 antibodies. RESULTS: Our cases were graded based on the degree of invasion of the myometrium. Ten were grade 1 (33.3%), 12 grade 2 (40%) and 8 grade 3A (26.7%). EVT invasion was best seen and evident by double immunostainings with actin-SM and cytokeratins, actin-SM and HPL, actin-SM and GATA3. CONCLUSION: The role of pathologist is decisive to determine the different grades of PAS. A better understanding of the depth of myometrial invasion can be achieved by the use of immunohistochemistry affording an important tool to obtain reproducible grading of PAS. This purpose is crucial in the setting of postoperative quality reviews and particularly in the forensic medicine field.

The Jellyfish Sign: A New Sonographic Cervical Marker to Predict Maternal Morbidity in Abnormally Invasive Placenta Previa.

PURPOSE: To investigate the value of a new cervical sonographic sign, called the jellyfish sign (JS), for predicting the risk of maternal morbidity in cases of abnormally invasive placenta (AIP) previa totalis. MATERIALS AND METHODS: Retrospective evaluation of transvaginal (TV) and transabdominal (TA) scans performed in all singleton pregnancies with placenta previa totalis. JS, i. e. the absence of the normal linear demarcation between the placenta previa and the cervix, was evaluated by TV scans. The presence/severity of AIP and outcomes of maternal morbidity were related to this sign. RESULTS: JS was noted in 8/39 (20.5 %) patients. The two analyzed groups, i. e. with and without JS, were similar. The specificity of JS in AIP diagnosis, histological findings of accreta/increta/percreta, need for caesarean hysterectomy or blood loss > 2000 ml ranges between 92 % and 96.2 %, with the PPV and NPV ranging between 71.4 % and 85.7 % and 61.3 % and 80.6 %, respectively. The JS group had a significant increase in blood loss (ml) (p = 0.003), transfusions (%) (p = 0.016), red blood cells (p = 0.002) and plasma (p = 0.002), admission to an postoperative intensive care unit (ICU) (%) (p = 0.002), hospitalization length (p < 0.001) and the need of cesarean hysterectomy (%) (p < 0.001). JS was independently correlated to cesarean hysterectomy (OR 25.6; 95 % CI 2.0:322.3, p = 0.012) and blood loss > 2000 ml (OR 16.6; 95 % CI 1.5:180.1, p = 0.021) also in a logistic regression model. CONCLUSION: JS is useful in predicting the increase in maternal morbidity: massive transfusion, admission to the ICU and cesarean hysterectomy related to intraoperative bleeding in patients with a previa AIP.