[The environmental impact of digital technology and artificial intelligence, in the time of digital pathology]. / Impacts environnementaux du numérique et de l'intelligence artificielle, à l'heure de la pathologie digitale.

While digitization and artificial intelligence represent the future of our specialty, future is also constrained by global warming and overstepping of planetary limits, threatening human health and the functioning of the healthcare system. The report by the Délégation ministérielle du numérique en santé and the French government's ecological planning of the healthcare system confirm the need to control the environmental impact of digital technology. Indeed, despite the promises of dematerialization, digital technology is a very material industry, generating greenhouse gas emissions, problematic consumption of water and mineral resources, and social impacts. The digital sector is impacting at every stage: (i) manufacture of equipment; (ii) use; and (iii) end-of-life of equipment, which, when recycled, can only be recycled to a very limited extent. This is a fast-growing sector, and the digitization of our specialty is part of its acceleration and its impact. Understanding the consequences of digitalization and artificial intelligence, and phenomena such as the rebound effect, is an essential prerequisite for the implementation of a sober, responsible, and sustainable digital pathology. The aim of this update is to help pathologists better understand the environmental impact of digital technology. As healthcare professionals, we have a responsibility to combine technological advances with an awareness of their impact, within a systemic vision of human health.

Molecular Analyses of Chorionic-Type Intermediate Trophoblastic Lesions: Atypical Placental Site Nodules are Closer to Placental Site Nodules Than Epithelioid Trophoblastic Tumors.

Gestational trophoblastic diseases derived from the chorionic-type intermediate trophoblast include benign placental site nodule (PSN) and malignant epithelioid trophoblastic tumor (ETT). Among PSNs, the World Health Organization classification introduced a new entity named atypical placental site nodule (APSN), corresponding to an ETT precursor, for which diagnostic criteria remain unclear, leading to a risk of overdiagnosis and difficulties in patient management. We retrospectively studied 8 PSNs, 7 APSNs, and 8 ETTs to better characterize this new entity and performed immunohistochemical analysis (p63, human placental lactogen, Cyclin E, and Ki67), transcriptional analysis using the NanoString method to quantify the expression of 760 genes involved in the main tumorigenesis pathways, and RNA sequencing to identify fusion transcripts. The immunohistochemical analysis did not reveal any significant difference in Cyclin E expression among the 3 groups (P = .476), whereas the Ki67 index was significantly (P < .001) higher in ETT samples than in APSN and PSN samples. None of the APSN samples harbored the LPCAT1::TERT fusion transcripts, in contrast to 1 of 6 ETT samples, as previously described in 2 of 3 ETT samples. The transcriptomic analysis allowed robust clustering of ETTs distinct from the APSN/PSN group but failed to differentiate APSNs from PSNs. Indeed, only 7 genes were differentially expressed between PSN and APSN samples; CCL19 upregulation and EPCAM downregulation were the most distinguishing features of APSNs. In contrast, 80 genes differentiated ETTs from APSNs, establishing a molecular signature for ETT. Gene set analysis identified significant enrichments in the DNA damage repair, immortality and stemness, and cell cycle signaling pathways when comparing ETTs and APSNs. These results suggested that APSN might not represent a distinct entity but rather a transitional stage between PSN and ETT. RNA sequencing and the transcriptional signature of ETT described herein could serve as triage for APSN from curettage or biopsy material, enabling the identification of cases that need further clinical investigations.

Association of Placental Mesenchymal Dysplasia With a Live Female Fetus and Complete Hydatidiform Mole: Report of a Challenging Case Confirmed by Molecular Genotyping Analysis.

Placental mesenchymal dysplasia (PMD) and complete hydatidiform mole (CHM) with a coexisting fetus are 2 rare placental abnormalities characterized by lacunar placenta and presence of an embryo on ultrasound examination. We report the case of a 34-yr-old woman referred at 32.6 weeks of gestation because of a multicystic placenta. A caesarean section was performed at 39.1 weeks of gestation giving birth to a 2905 g normal female infant. Pathological examination revealed macroscopic and microscopic morphological, and immunohistological features of PMD in the main placenta, and features of CHM in a separate placental mass. Fluorescent in situ hybridization and molecular genotyping analyses showed diandric diploidy in the CHM component and androgenetic/biparental mosaicism in the PMD component, confirming the association of PMD and CHM with a live infant. There was no progression to gestational trophoblastic neoplasia during follow-up for the mother, or any sign of Beckwith-Wiedemann syndrome or hepatic tumor in the child.

Placental Pathology in Beckwith-Wiedemann Syndrome According to Genotype/Epigenotype Subgroups.

OBJECTIVES: To evaluate the frequency of placental pathological lesions in Beckwith-Wiedemann syndrome (BWS), an overgrowth disorder that exhibits etiologic molecular heterogeneity and variable phenotypic expression. MATERIALS AND METHODS: The study included 60 BWS patients with a proven molecular diagnosis and a placental pathological examination. Placentomegaly, placental mesenchymal dysplasia (PMD), chorangioma/chorangiomatosis, and extravillous trophoblastic (EVT) cytomegaly were evaluated and their frequencies in the different molecular subgroups were compared. Immunohistochemistry and fluorescent in situ hybridization (FISH) were performed on EVT cytomegaly. RESULTS: Placentomegaly was found in 70.9% of cases, PMD in 21.7%, chorangioma/chorangiomatosis in 23.3%, and EVT cytomegaly in 21.7%; there was no significant intergroup difference. EVT cytomegaly showed loss of p57 expression, increased Ki67 proliferating index, and polyploidy on FISH analysis. CONCLUSIONS: There was no genotype/epigenotype-phenotype correlation concerning placental lesions in BWS. Diffuse EVT cytomegaly with polyploidy may represent a placental finding suggestive of BWS.

[Pseudosarcomatous chorangioma: A macroscopic and microscopic atypical tumor]. / Chorangiome pseudosarcomateux : une tumeur atypique sur le plan macroscopique et microscopique.

We report a case of an unusual chorangioma in a 26-year-old gravida 2, para 1 female. The clinical course was complicated by premature birth at 34 weeks' gestation. The baby presented with congenital cardiac and renal malformations. The tumor was 11 cm in size, separated from the main placental mass and exhibited atypical histologic characteristics such as fibromatous areas, high cellularity, nuclear atypia and high mitotic index. These histologic features must not be interpreted as malignancy.

[Gestational trophoblastic disease]. / Les maladies trophoblastiques gestationnelles.

Gestational trophoblastic disease encompresses a group of interrelated diseases, following a pregnancy after a variable period of time. Hydatiform mole corresponds to premalignant disorders composed of villi with excess of paternal genetic material, with a malignant potential more important for complete mole than partial mole. Gestational trophoblastic neoplasia includes invasive mole, choriocarcinoma, placental site trophoblatic tumor and epithelioid trophoblastic tumor. Their histological diagnosis may be problematic on curettage material and needs to be correlated to serum hCG level and radiological findings. The use of chemotherapy has dramatically improved the prognosis of these lesions. All patients with this rare disease need to be registered in the national service for gestational trophoblastic disease (http://www.mole-chorio.com), which coordinates their management at the national level.

The carbon footprint of a surgical pathology laboratory in France.

OBJECTIVES: The health sector contributes to climate disruption through greenhouse gas (GHG) emissions. It accounts for 8% to 10% of France's GHG emissions. Although the medical community has been alerted to the problem, more data are needed. This study aimed to determine the carbon footprint of a surgical pathology laboratory. METHODS: The study was conducted in the surgical pathology laboratory at Saint Vincent hospital (Lille) in 2021. It represented 17,242 patient cases corresponding to 54,124 paraffin blocks. The 17 staff members performed cytology, immunohistochemistry, and in situ hybridization. The study included all inputs, capital equipment, freight, travel, energy consumption, and waste. Carbon emission factors were based on the French Agence De l'Environnement et de la Maîtrise de l'Energie database. RESULTS: In 2021, the pathology laboratory's carbon footprint was 117 tons of CO2 equivalent (t CO2e), corresponding to 0.5% of Saint Vincent hospital's total emissions. The most significant emissions categories were inputs (60 t CO2e; 51%), freight associated with inputs (24 t CO2e; 20%), and travel (14 t CO2e; 12%). Waste and energy generated 10 t CO2e (9%) and 9 t CO2e (8%), respectively. CONCLUSIONS: The pathology laboratory's carbon footprint was equivalent to the yearly carbon impact of 11 French inhabitants. This footprint is dominated by inputs and associated freight. This suggests an urgent need to develop ecodesign and self-sufficiency in our routine practices.

Predictive factors for severe placental damage in pregnant women with SARS-CoV-2 infection.

INTRODUCTION: SARS-Cov-2 infection during pregnancy can lead to severe placental lesions characterized by massive perivillous fibrin deposition, histiocytic intervillositis and trophoblast necrosis. Diffuse placental damage of this kind is rare, but can sometimes lead to obstetric complications, such as intrauterine fetal death (IUFD). The objectives of this study were to identify possible predictors of severe placental lesions. METHODS: We retrospectively studied 96 placentas from SARS-Cov-2 positive pregnant women who gave birth between March 2020 and March 2022. Cases with and without severe placental lesions were compared in terms of clinical and laboratory findings. RESULTS: Twelve of the 96 patients had severe placental lesions. There was no significant association with diabetes, obesity or severe clinical maternal disease. In contrast, presence of severe placental lesions was significantly associated with neonatal intensive care, cesarean section, prematurity, IUFD, intrauterine growth restriction (IUGR), gestational age, maternal hypofibrinogenemia and thrombocytopenia. No cases of severe placental lesions were observed in vaccinated patients or in those with the Omicron variant. DISCUSSION: In these patients, severe placental lesions due to SARS-Cov-2 were significantly associated with the presence of coagulation abnormalities (hypofibrinogenemia and thrombocytopenia), IUGR and gestational age. These results support laboratory and ultrasound monitoring of these parameters in pregnant women with SARS-Cov-2 infection, especially during the second trimester, to predict potential negative fetal outcomes.

Androgenetic/biparental mosaicism in a diploid mole-like conceptus: report of a case with triple paternal contribution.

Hydatidiform moles (HMs) are divided into two types: partial hydatidiform mole (PHM) which is most often diandric monogynic triploid and complete hydatidiform mole (CHM) which is most often diploid androgenetic. Morphological features and p57 immunostaining are routinely used to distinguish both entities. Genetic analyses are required in challenging cases to determine the parental origin of the genome and ploidy. Some gestations cannot be accurately classified however. We report a case with atypical pathologic and genetic findings that correspond neither to CHM nor to PHM. Two populations of villi with divergent and discordant p57 expression were observed: morphologically normal p57 + villi and molar-like p57 discordant villi with p57 + stromal cells and p57 - cytotrophoblasts. Genotyping of DNA extracted from microdissected villi demonstrated that the conceptus was an androgenetic/biparental mosaic, originating from a zygote with triple paternal contribution, and that only the p57 - cytotrophoblasts were purely androgenetic, increasing the risk of neoplastic transformation.

A novel NLRP7 protein-truncating mutation associated with discordant and divergent p57 immunostaining in diploid biparental and triploid digynic moles.

NLRP7 is a maternal-effect gene that has a primary role in the oocyte. Its biallelic mutations are a major cause for recurrent diploid biparental hydatidiform moles (HMs). Here, we describe the full characterization of four HMs from a patient with a novel homozygous protein-truncating mutation in NLRP7. We found that some HMs have features of both complete and partial moles. Two HMs expressed p57 in the cytotrophoblast and stromal cells and exhibited divergent and discordant immunostaining. Microsatellite DNA-genotyping demonstrated that two HMs are diploid biparental and one is triploid digynic due to the failure of meiosis II. FISH analysis demonstrated triploidy in the cytotrophoblast and stromal cells in all villi. Our data highlight the atypical features of HM from patients with recessive NLRP7 mutations and the important relationship between NLRP7 defects in the oocyte and p57 expression that appear to be the main contributor to the molar phenotype regardless of the zygote genotype.

p57-discordant villi in hydropic products of conception: a clinicopathological study of 70 cases.

p57 immunostaining is performed on hydropic products of conception to diagnose hydatidiform moles (HMs), which can progress to gestational trophoblastic neoplasia. Partial hydatidiform mole (PHM) and hydropic abortion (HA) display positive staining in stromal and cytotrophoblastic cells, whereas complete hydatidiform mole (CHM) is characterized by loss of p57 expression in both cell types. In some cases, an aberrant pattern is observed, called discordant p57 expression, with positive cytotrophoblast staining and negative stromal staining, or vice versa. The aim of this study was to describe the clinical, biological, and pathological characteristics of p57-discordant villi (p57DV) and other associated populations in cases of divergent p57 expression and to compare the evolutions of p57DV-associated and classic CHMs. Seventy cases of p57DV diagnosed by referent pathologists were divided into two groups, G1: p57DV ± non-CHM component (n = 22) and G2: p57DV + CHM component (n = 48). p57DV morphology was similar in the two groups. Observation of more than two populations and hybrid villi on p57 immunostaining were significantly more frequent in G2. The clinical, ultrasound, and biological presentations of p57DV-associated and classic CHMs were similar. The initial pathological diagnosis was more frequently incorrect, missing the CHM component, for the p57DV-associated CHMs. Molecular genotyping was informative in seven cases and identified as androgenetic/biparental mosaicism in four cases. These results show that p57DV are a diagnostic challenge for pathologists and that most are associated with a CHM component. However, the clinical management of p57DV-associated CHMs should be the same as that of classic CHMs.