Diagnostic Pathology最新文献

Background: Perivascular epithelioid cell tumor (PEComa) of the pancreas is a rare tumor of pancreatic mesenchymal origin with malignant potential. Critical to appropriate clinical management is determining whether the tumor is benign or malignant. Because of its rarity, morphologic and histologic characteristics and limited patient follow-up of pancreatic PEComa have precluded precise definition of malignancy. However, because malignant pancreatic PEComa appears to be distinctly uncommon, further improvements characterizing its preoperative imaging features could facilitate use of diagnostic endoscopic ultrasound biopsy and perhaps ablative treatment. This paper presents a case of pancreatic PEComa treated at the Affiliated Hospital of North Sichuan Medical College and includes a systematic literature review with special emphasis on the key imaging features of pancreatic PEComa.

Case presentation: In February 2024, a woman in her 50s was admitted to the hospital with subxiphoid discomfort. Magnetic resonance imaging (MRI) of the upper abdomen revealed a round, solid mass in the pancreatic uncinate process. The patient underwent pancreatic mass resection and pancreaticojejunostomy, and the diagnosis of pancreatic PEComa was confirmed through pathological examination.

Conclusions: Imaging examinations appear valuable for a tentative diagnosis of pancreatic PEComa. Key imaging features include its frequent occurrence in the pancreatic head, typically small to moderate size, "pushing" as opposed to infiltrative growth pattern with well-defined margins, and the presence of a capsule. The lesions are usually solid and often exhibit mild to moderate heterogenous enhancement during the arterial phase, with reduced enhancement in the portal and delayed phases.

Introduction: Muscle-invasive bladder cancer (MIBC) is a heterogeneous disease with variable outcomes, necessitating practical classification systems. Molecular subtyping using immunohistochemical (IHC) markers offers a cost-effective approach for therapeutic guidance and assessing survival. Moreover, MIBC molecular subclassification provides a practical approach for guiding immune checkpoint inhibitor therapy.

Methods: We evaluated 124 MIBC cases using IHC markers GATA3, CK5/6, and p16. Cases were classified as luminal (GATA3+, CK5/6-), basal (GATA3-, CK5/6+), or other (GATA3-, CK5/6-). Luminal cases were further subdivided into luminal unstable (LumU; p16+) and luminal papillary (LumP; p16-). Clinicopathological characteristics of MIBC molecular subtypes were also assessed. PD-1 and PD-L1 expression were evaluated relative to clinicopathological features and MIBC subtypes.

Results: In our study, 36.2% of the cases were LumU, 27.6% LumP, and 24.8% basal. The basal subtype generally shows a significantly higher tumor stage (p < 0.05). PD-1 was expressed in 70.5% of cases, with the highest expression in LumU (84.21%). PD-1 expression was significantly higher in the luminal compared to the basal subtype (82.1% vs. 53.8%, p < 0.01). PD-L1, expressed in 40% of cases, was significantly elevated in stage III and considerably higher in basal than luminal subtype (57.7% vs. 34.3%, p < 0.05).

Conclusion: MIBCs were practically subclassified into LumU, LumP, basal, and other subtypes using three IHC markers. PD-1 expression was higher in the luminal subtype, while PD-L1 was predominantly elevated in the basal subtype. These findings highlight the potential of IHC-based subtyping to guide prognosis and treatment in MIBCs.

Background: Bladder cancer is characterized by its heterogeneous nature and high propensity for recurrence and progression. The absence of reliable diagnostic and prognostic biomarkers to accurately identify high-risk patients further complicates the clinical management of the disease. MOC-31, an antibody that targets epithelial cell adhesion molecule (EpCAM), is utilized to distinguish between mesothelioma and metastatic cancer, but its clinical utility, prognostic value and functional dynamics in bladder cancer have yet to be verified.

Methods: A comprehensive analysis of EpCAM expression and its associations with key clinicopathological parameters was performed via The Cancer Genome Atlas (TCGA). Additionally, we retrospectively assessed EpCAM expression in our bladder cancer cohort using MOC-31 antibody and examined its prognostic value and correlation with clinicopathological features. The cBioPortal, STRING and TIMER databases were used to explore the interactions between EpCAM expression, immune cell infiltration and immune checkpoint genes.

Results: The difference in EpCAM expression varied widely across various cancer types and was strongly correlated with advanced cancer stage. EpCAM staining with MOC-31 exhibited membranous positivity in 51.7% of the analysed cohort. Kaplan-Meier survival analysis revealed a discernible trend suggesting a poorer prognosis for patients with low EpCAM expression than for those with high EpCAM expression. Protein-protein interaction demonstrated that EFGR, HER2 and Claudin-7 are key EpCAM interactors. A strong association was observed between EpCAM expression and immune cell infiltration as well as immune-related genes.

Conclusion: This study highlights the prognostic value of EpCAM in bladder cancer, revealing a strong link between EpCAM expression and disease pathogenesis. These results underscore the need for further research to validate these findings and explore the significance of EpCAM as a therapeutic target in managing bladder cancer.

Uterine inflammatory myofibroblastic tumour (IMT) is a relatively rare mesenchymal tumour of the uterus, with recurrence and metastasis rates of 25% and 2%, respectively. As IMT frequently harbours ALK gene rearrangements, some patients may benefit from treatment with tyrosine kinase inhibitors, making accurate identification of this tumour essential. Here, we report the case of a 38-year-old female patient with a tumour clinically resembling uterine leiomyoma. Microscopically, the spindled tumour cells were arranged in orderly intersecting fascicles, accompanied by a sparse infiltrate of inflammatory cells and a notable absence of myxoid matrix. Immunohistochemistry and molecular testing revealed an ALK::SYN3 fusion, suggesting the diagnosis of a uterine leiomyoma-like inflammatory myofibroblastic tumour (UL-like IMT). UL-like IMT is exceedingly rare and can easily be misdiagnosed as smooth-muscle tumours based solely on clinical manifestations and morphology. Therefore, it is recommended that the diagnosis be based on a combination of histopathological features, immunohistochemical markers, and genetic testing results to ensure a comprehensive and accurate assessment.

Purpose: To comprehensively analyze the clinical data of histiocytic necrotizing lymphadenitis (HNL) in adults with fever of unknown origin (FUO), with the aim of enabling precise diagnosis.

Patients and methods: A total of 15 HNL patients with FUO were enrolled. The analysis encompassed clinical manifestations, laboratory parameters ¹⁸F-Fluorodeoxyglucose Positron Emission Tomography/Computed Tomography (¹⁸F-FDG PET/CT) imaging profiles, pathological features and therapeutic responses.

Results: All patients presented with fever and lymphadenopathy (predominantly cervical). Laboratory findings included leukopenia (3.28 × 10⁹/L [2.40-4.97]), elevated LDH (306 U/L [187-524]), ESR (40 mm/h [30-51]), ferritin (457.1 ng/mL [206-1823.3]), and CRP (25 mg/L [6.1-34.8]) ¹⁸F-FDG PET/CT detected metabolic lymph node abnormalities in 13 cases, primarily cervical and axillary. The pathological features were extensive coagulative necrosis of lymph nodes with reactive hyperplasia of histiocytes as well as positive or scattered positivity IHC CD3, CD4, CD8 and CD68. Corticosteroid achieved favorable responses, with only 2 cases progressing during follow-up.

Conclusion: In clinical practice, patients with fever and lymphadenopathy should be given due attention. Pathological examination remains the gold standard for diagnosing HNL. Glucocorticoid therapy has proven effective, and the majority of patients with HNL exhibit a favorable prognosis.

Background /objectives: Preanalytic quality control of surgical specimens is often inadequately managed. This study aimed to share the experience of improving quality through the implementation of a system for preanalytic surgical specimens.

Methods: After initial workflow mapping and process optimization, a pathology specimen transfer system was piloted and subsequently implemented hospital-wide. Ongoing monitoring and adjustments were made based on established standards and operational needs. Data were analyzed using R Studio software.

Results: The system reduced errors from 24.82 to 2.40%, including reductions of 86.85% in requisition mistakes, 95.30% in label errors, and 100% in illegible handwriting. From 2020 to 2023, the interval between specimen removal and submission was halved, and delayed fixation decreased from 0.46 to 0.22%.

Conclusions: The system effectively standardized processes, enhanced efficiency, and reduced errors in preanalytic surgical specimens. Quality improvement was dependent on thorough workflow mapping and optimization, as well as ongoing monitoring and adjustments.

Introduction: Secretory Carcinoma (SC) of the thyroid is a relatively new and often misdiagnosed cancer. Like SC of the breast and salivary gland, it is characteristically diffusely positive for S100 and Mammaglobin by immunohistochemical (IHC) staining.

Methods: Case report.

Results: A 63-year-old female presented with neck swelling and difficulty breathing. CT scan showed a large thyroid mass. Tracheal compression and deviation required stent placement and urgent radiation. Microscopic analysis showed neoplastic cells with frequent intracytoplasmic globules, including signet-ring cells. IHC stains were inconclusive to tumor type and metastasis from an occult primary was considered. However, PET-CT scan, mammography, and upper endoscopy were negative. Next-generation sequencing was performed revealing an ETV6-NTRK3 fusion favoring SC of the thyroid.

Conclusions: SC of the thyroid with unusual histomorphology and IHC staining may be overlooked and can mimic a metastasis. Given that a correct diagnosis critically affects prognosis and treatment, pitfalls can be avoided by utilizing molecular testing in complicated cases.

Purpose: Primary bilateral macronodular adrenal hyperplasia (PBMAH) is a rare subtype of Cushing's syndrome, with some cases exhibiting a familial aggregation tendency. The heterogenous expression of CYP11B1 mRNA among multiple adrenal nodules in PBMAH had not been previously reported. This study aims to investigate the correlation between CYP11B1 mRNA expression and Hounsfield unit (Hu) density in computed tomography (CT) scans in a patient with ARMC5 mutated PBMAH.

Methods: A 47-year-old male came to our hospital for headache and hypertension. He was diagnosed as PBMAH later and received adrenalectomy. DNA sequencing was performed on the patient's peripheral blood, his relatives' peripheral blood, and the patient's adrenal tissues. Additionally, four different adrenal nodules from the patient were collected to explore the relationship between CYP11B1 mRNA expression and Hu density in CT scanning.

Results: A family with autosomal dominant inherited PBMAH was identified. Second generation sequencing of peripheral blood and Sanger sequencing of adrenal tissues identified a novel ARMC5 pathogenic variant, c.1865-2_1865-1del, which was also present in the patient's brother, sister and nephew. The patient's adrenal was enlarged diffusely but cushingoid feature was not severe. The adrenal imaging showed bilateral macronodules resembling adrenal tumors. Notably, the Hu values varied significantly among different nodules, and interestingly, the CYP11B1 mRNA expression was found to be parallel to the Hu values.

Conclusions: We reported a family of PBMAH with novel ARMC5 pathogenic variant. The index patient exhibited heterogeneous adrenal nodules with distinct Hu values and CYP11B1 mRNA levels.

Background: Spindle epithelial tumor with thymus-like differentiation or elements (SETTLE) is a rare and malignant biphasic tumor of the thyroid that has proven challenging to diagnose by cytology.

Case presentation: A 20-year-old-male presented with a large left neck nodule and neck tightness. Laboratory tests were normal. Computed Tomography (CT) of the neck revealed a thyroid mass involving the isthmus and entire left lobe. Ultrasound-guided fine needle aspiration of the mass demonstrated sheets and clusters of oval to spindle cells with associated fibrovascular cores. The cells had moderately pleomorphic nuclei with stippled chromatin, inconspicuous nucleoli, and minimal cytoplasm, and a diagnosis of medullary thyroid carcinoma was made. A total thyroidectomy and neck dissection was performed. Morphological and immunohistochemical evaluation of the specimen resulted in a diagnosis of SETTLE with angioinvasion and involved lymph nodes.

Conclusion: SETTLE has several mimics cytologically, such as medullary thyroid carcinoma, that makes accurate pre-operative diagnosis challenging. We present a review of cytology information from literature, highlighting features that differentiates SETTLE from its mimics.

Background: Ewing's sarcoma (ES), first described by Ewing in 1921, is a highly malignant small blue round cell tumor that arises in bone or extraskeletal soft tissues. It predominantly affects patients aged 10 to 30 years. Approximately 12% of cases involve solid organs, often presenting as rapidly growing masses in deep soft tissues. The most common genetic alteration in ES is the t(11;22)(q24;q12) translocation, resulting in the EWSR1::FLI1 fusion gene, which accounts for 90% of tumors. Extraskeletal Ewing's sarcoma (EES) presented as a breast mass is extremely rare, with only a handful of cases documented in the literature. Notably, a primary breast ES harboring the EWSR1::ERG fusion gene has never been reported previously.

Case presentation: A 23-year-old woman presented to our hospital with a rapidly growing, palpable left breast mass. Histopathological examination of the surgical specimens (including histological features, immunohistochemical staining, and molecular analysis) confirmed the diagnosis of primary EES with EWSR1::ERG translocation in the breast. Despite receiving multimodal adjuvant therapy (surgery, chemotherapy and radiotherapy), the patient experienced two disease relapses within 15 months.

Conclusions: Our report establishes the first molecularly confirmed case of ES harboring the rare EWSR1::ERG translocation presenting as a primary breast mass. Primary breast ES can demonstrate significant morphologic and immunohistochemical overlap with other small round cell tumors. This case highlights that next-generation sequencing (NGS) is the gold standard for definitive diagnosis, as it reliably detects fusion partners-especially in rare tumors arising in uncommon locations.