Meningothelial-type pulmonary nodules are benign and relatively common, often incidentally discovered in nearly half of properly sampled lobectomy specimens. Diffused pulmonary meningotheliomatosis is a very rare condition, the origin of which remains unknown.

Micro-computed tomography (micro-CT) offers high-resolution, three-dimensional imaging of embryonic structures, overcoming limitations of standard autopsy in early loss of pregnancy.

Fine needle aspiration is a well-known procedure for the diagnosis and management of solid lesions. The approach to cystic lesions on fine needle-aspiration is becoming a popular diagnostic tool due to the increased availability of high-quality cross-sectional imaging such as computed tomography and ultrasound guided procedures like endoscopic ultrasound. Cystic lesions are closed cavities containing liquid, sometimes partially solid with various internal neoplastic and non-neoplastic components. The most frequently punctured cysts are in the neck (thyroid and salivary glands), mediastinum, breast and abdomen (pancreas and liver). The diagnostic accuracy of cytological cyst sampling is highly dependent on laboratory material management. This review highlights how to approach the main features of superficial and deep organ cysts using basic cytological techniques (direct smears, cytocentrifugation), liquid-based cytology and cell block. We show the role of a multimodal approach that can lead to a wider implementation of ancillary tests (biochemical, immunocytochemical and molecular) to improve diagnostic accuracy and clinical management of patients with cystic lesions. In the near future, artificial intelligence models will offer detection, classification and prediction capabilities for various cystic lesions. Two examples in pancreatic and thyroid cytopathology are particularly developed.

Cystic diseases are a group of diseases characterised by the formation of cysts in some organs, particularly the lungs and kidneys, which progressively lead to respiratory or renal failure, requiring organ transplantation in advanced cases. Understanding the mechanisms of these cystic diseases has led to advances in early detection and the development of new treatments to slow their progression to end-stage failure.

The pathology report is a critical source of medical information. It must evolve from a traditionally narrative format, regardless of its qualitative value, toward a communication medium based on standardised and structured data. Already useful in current practice, the standardised structured reporting (SSR) will become a cornerstone of digital pathology, in synergy with digital imaging and artificial intelligence. The reliability of the SSR and the precision of the data it provides, correlated with multimodal sources of clinical, radiological, or biological information, will contribute to the foundations of highly performant digital solutions. Despite its considerable potential, the SSR remains underutilised. Although the concept was favourably received by the specialty twenty years ago, the SSR has often been described as insufficiently scalable, poorly ergonomic, and a source of time loss in daily practice. Once challenged by the capacity of natural language processing (NLP) to structure retrospectively narrative reports, the SSR ultimately emerges as the most reliable data source for effective patient care and high-performing research. New tools developed within the framework of the national Impulsioninitiative should help overcome these reluctances and open concrete perspectives for pathologists from now on.

The 2021 World Health Organisation (WHO) classification of tumours of the central nervous system introduced molecular biomarkers (homozygous deletion of CDKN2A/B and TERT promoter mutation) in the grading of meningiomas. Since, the cIMPACT-NOW consortium has proposed a new prognostic algorithm (published in the update 8), integrating epigenetic and genetic data. The aim of the study was to report on the experience of the neuropathology department of Sainte-Anne Hospital in integrating this algorithm into the gradingof meningiomas.

The 10 semesters that make up the French pathology residency enable residents to discover the different types of practice possible in this specialty. The varied experiences acquired by students over the course of these semesters contribute to their decision as to where and how they wish to practice. This decision involves both intrinsic and extrinsic factors regarding the practice setting considered. The aim of this study was to examine the weight of the various criteria involved in this decision among French pathology residents. To this end, a questionnaire comprising 33 questions was submitted to this population between November 2024 and January 2025. Responses from 115 residents from 21 university hospitals were collected, with a more significant representation of fifth-year residents compared to first-year ones. The location of the future place of practice was not a decisive factor in the students' choice. On the contrary, the search for a certain quality of life, both in and out of the workplace, was highlighted by the residents. Activities associated with working in a university hospital, such as research or teaching, were not decisive factors in their decision. The results of this study highlight some motivating or limiting criteria that influence French pathology residents in their choice of future place and mode of professional practice.

Liver involvement in Li-Fraumeni syndrome is usually due to primary or metastatic malignant tumors. We report a case in which multiple liver nodules proved to be benign lesions. This 30-year-old female patient, with a known Li-Fraumeni syndrome and a history of several previous malignancies, presented multiple liver nodules detected at systematic annual screening. Two were suggestive of focal nodular hyperplasia. Three others were fat-containing at imaging studies; a guided biopsy of the largest lesion, measuring 15mm in diameter, concluded to liver angiomyolipoma, of mixed composition, combining adipocyte-like cells, dystrophic vascular structures, spindle cells and epithelioid cells coexpressing smooth muscle and melanocytic markers. There was no adverse histopathological feature. A simple surveillance was decided. The possible occurrence of benign lesions during Li-Fraumeni syndrome, requiring only conservative management after histopathological diagnosis, must be known, especially with the increasing use of annual whole-body imaging for screening.

Spinal arachnoid cysts are rare benign lesions filled with cerebrospinal fluid and lined by an arachnoid membrane. We report an observation of an intradural arachnoid cyst in the lumbar region causing spinal cord compression.

We report the case of a 24-year-old patient affected by Epstein syndrome, in whom a CT scan performed in a traumatic context revealed numerous splenic lesions. After hemostatic splenectomy, the pathological examination showed splenic well-limited, non-encapsulated nodules, consisting of dilated venous sinuses, filled with red blood cells with inter-connected anfractuous vascular structures. These lesions had the following double endothelial and histiocytic immunohistochemical profile: CD31+, Factor VIII+, CD34+, ERG+, D2/40-, CD68+, CD21+/-. This is the second case reported in the literature of littoral cell angioma in association with Epstein syndrome.

We report the case of a 45-year-old woman in whom a solitary 5.5cm hepatic tumor was discovered during oncologic surveillance for a papillary thyroid carcinoma diagnosed ten years earlier. Biopsy revealed a tumor cell proliferation with "endocrinoid" morphology and convincing immunohistochemical expression of neuroendocrine markers, initially suggesting a well-differentiated grade 3 neuroendocrine tumor. FDG-PET/CT demonstrated isolated hypermetabolic activity in the liver lesion, with no corresponding uptake on DOTATOC-PET. Following neoadjuvant chemotherapy, the patient underwent segmental liver resection. Histopathological examination of the resected specimen showed a proliferation of monomorphic cells with ovoid nuclei, arranged in a tubulo-solid architecture, with focal areas reminiscent of a "thyroid-like" pattern. Tumor cells exhibited heterogeneous expression of neuroendocrine markers and strong, diffuse positivity for alpha-inhibin. RNA sequencing identified a NIPBL::NACC1 fusion transcript, leading to a revised diagnosis of hepatic carcinoma with NIPBL::NACC1 fusion. This recently described and rare hepatic tumor is challenging to diagnose on biopsy. Histologically, it is characterized by a monomorphic ovoid cell proliferation with a tubulo-solid growth pattern and focal thyroid-like morphology. Neuroendocrine marker expression is variable, but strong and diffuse alpha-inhibin staining is a consistent feature.

Digital pathology and microscopic image analysis using artificial intelligence (AI) will revolutionize practice and diagnosis in pathology. The implementation and use of AI models in clinical workflows within digital pathology raise numerous questions regarding the role of these new tools. Alongside commercial software solutions, the use of free software and "in-house" models can be an attractive strategy, promoting the adoption of these new technologies by pathologists while addressing their diagnostic needs without constraints related to data flow or funding. The appropriate use of the right diagnostic model - subject to the continuous scrutiny of the pathologist in charge  - is key to the integration of AI tools into clinical practice. This article presents an experience in implementing free and "in-house" AI tools based on the use of the QuPath software and its extensions within a digital pathology workflow.

Molecular analyses performed on cell and tissue samples play a major diagnostic, prognostic, and theragnostic role. Their complexity and diversity, as well as that of the biological matrix involved (formalin-fixed paraffin-embedded tissue, frozen tissue, cytological sample, liquid biopsy), are increasing. The tumor cell content of the sample is an important limiting factor as well as the quality and quantity of nucleic acids extracted from the initial matrix. Therefore, it is crucial to understand and manage the conditions of sample preparation and storage, as those will directly impact the quality of the extracted material and constrain the types of analyses that will be performed. This article highlights the key pre-analytical steps as well as the limitations and interpretative biases that may result from mishandling of the samples.

Peripheral neuroblastic tumors correspond to a generic term for a heterogeneous spectrum of tumors: neuroblastomas, ganglioneuroblastomas (mixed and nodular), and ganglioneuromas. In current practice, the term neuroblastoma is often used because it represents the most frequent and most aggressive tumor component. It is a common tumor in children with heterogeneous morphological, biological and clinical presentations, but with an often unfavorable prognosis. The histoprognostic classification defined by the International Neuroblastoma Pathology Committee is still the reference classification for establishing a prognosis. It must be performed on representative samples containing at least 5 000 cells at the time of diagnosis, before any treatment. It is essentially based on the patient's age, the differentiation of tumor cells, the abundance of schwannian stroma and the mitotic and karyorrhexic index. Immunohistochemical studies may help to make the diagnosis. Very specific tumor markers have been described and may be associated with stromal markers. Immunohistochemical prognostic markers are currently being evaluated. Molecular analysis, which is essential for establishing the prognosis, should be performed on fresh samples. These tumors, which are common in fetuses and rare in adults, display different morphology and prognosis depending on the age at diagnosis. In adults, composite adrenal tumor variants are more common and must be kept in mind. The histopathological examination of neuroblastomas is a key step for optimal management of these pediatric tumors.