Diagnostic Histopathology最新文献

Parathyroid carcinoma (PTC) is an uncommon endocrine neoplasm. There are well-established criteria for its diagnosis, but diligent practical application of these criteria can be challenging for even the most discerning pathologist. We report a case of PTC demonstrating classical lymphovascular invasion, and review how pathologists can confidently and effectively diagnose PTC utilising the correct morphological histopathological features, supported by a panel of immunohistochemical stains and ancillary molecular testing.

This article briefly describes the pathology of the parathyroid gland seen commonly in routine practice and the application of recent WHO terminologies in practice. The commonest clinical presentation is hypercalcaemia due to hyperparathyroidism. Diagnosis of parathyroid lesions requires the integration of clinical, biochemical, surgical and histopathological features. MDT discussion and optimized clinical information support the pathological features. Often, histological specimens require a detailed workup including processing the entire gland, further levels and sectioning, and ancillary testing. The new WHO guidance provides a detailed genetic and molecular correlate for the histological features. Genetic and molecular pathogenetic mechanisms are described introducing new nomenclature replacing some traditional terminology. This article is not a replacement for various guidance available, it tries to resolve some routine histological conundrums. The readership is therefore encouraged to access further reading material from the WHO guidance, ICCR guidance and RCPath guidance.

Thyroid follicular nodular disease (FND), formerly known as multinodular goitre is one of the commonest thyroid pathologies and can show variable clinical presentation and a variety of histopathologic features. The microscopic features of thyroid FND can sometimes mimic those of well-differentiated thyroid malignancies. It is important to recognise this range of appearances to avoid over diagnosis of neoplasia. Macroscopic examination of thyroid specimens and correlation with microscopic features can be helpful in interpreting nodules with atypical appearances. We describe the variety of histologic features which can be encountered in thyroid FND. We also describe how fibrosis and other changes secondary to haemorrhage and inflammation in thyroid FND can produce worrisome histologic appearances, in and around nodules which can be misinterpreted as invasive malignancy. This review aims to update on the histopathology of thyroid FND and to focus on pitfalls in microscopic interpretation.

Flat urothelial lesions are common and recognition is important for patient management. Over- and undertreatment can be a consequence of misdiagnosis. Reporting the right diagnosis is also important for the follow-up. We describe the most frequent entities with a focus on clinical meaning. Several of these described lesions do not figure in the WHO 2022 classification; therefore knowledge of them is important. We also discuss benign, precursor and malignant lesions and suggest the latest nomenclatures given by international societies. Molecular data, as far as currently known, are included where possible. The aim is to give a practical and precise overview of this complicated topic.

This is the case of a 45 year old male patient with an oncocytic renal neoplasm that was difficult to classify. Histology from a partial nephrectomy revealed a tumour comprising oncocytic cells containing rounded nuclei with some prominent nucleoli, although no necrosis or lymphovascular invasion. CK7 immunohistochemistry was focally positive, with only weak staining for CD117. There are multiple lesions to consider in the differential diagnosis of oncocytic renal tumours with borderline features between oncocytoma and chromophobe carcinoma. The increasing use of molecular pathology is also important in the diagnosis of some entities.

Testis tumors are the most common malignancies in young men. The most common testis tumors are germ cell tumors (GCT) that are considered curable diseases due to excellent prognosis. Management of GCT begins with radical orchiectomy. Once the specimen arrives on pathologist's bench, accurate diagnosis begins with obtaining proper clinical history, careful macroscopic examination, and proper sampling. Finally, the information provided by pathologist outlines the need for further treatment, clinical behavior, and outcome of tumor. Therefore, proper assessment of the tumor type and stage by the pathologist is of utmost significance. In this manuscript, we will review some of the most common pitfalls of the diagnosis and reporting the GCTs based on the observation of our referral cases.

The gross handling of and reporting of renal cell carcinoma in the setting of neoadjuvant immune checkpoint inhibitor therapy presents unique challenges, and there is little known about the spectrum of histologic changes that can be seen in this setting. We studied 70 cases of RCC, status post immunotherapy and nephrectomy at our institute and devised a standardized grossing protocol to help assess pathologic response. Our protocol includes sampling a complete cross section of the largest diameter of tumor with additional sections from areas of gross extrarenal involvement. Percentage of necrosis is calculated by assessing gross and microscopic necrosis and reporting an approximate average. Common histologic changes included fibrosis, myxoid change, necrosis and a chronic inflammatory infiltrate. Additionally, we found a discrepancy between the gross and the microscopic stages in 15 cases and all cases were of a lower pathologic stage than was suggested by the gross examination. We conclude that conventional staging guidelines may not apply to this unique cohort of cases, as using the gross estimate of tumor can falsely overestimate residual tumor burden. It is our recommendation to only assign a pathologic stage based on the location of the viable microscopic tumor. Before downstaging a tumor with grossly visible tumor outside the kidney, extensive sampling should be done in these areas to exclude microscopic tumor involvement.

Advancements in molecular pathology have initiated a transformative era in the diagnostic classification and treatment of urological cancers. The 2022 WHO classification exemplifies this evolution by introducing molecularly defined renal cell carcinoma entities. The synthesis of clinical, pathological, and molecular findings leveraging large-scale technologies like next-generation sequencing (NGS) has led to a significant acceleration of precision oncology. Predictive biomarker testing has gained significant importance in urological malignancies, especially in urothelial cancer and prostate cancer underscored by novel targeted drugs like Erdafitinib and PARP inhibitors. Furthermore, immunotherapy has emerged as a central pillar in managing kidney cancer and urothelial cancer. Given the circumstance that many precision oncology trials are currently on the way, molecular diagnostic and especially predictive uropathology will rapidly evolve in the upcoming years. The present review focuses on new developments in molecular uropathology in both fields, diagnostic and predictive molecular uropathology.

Microscopic colitis presents as chronic watery diarrhoea and leads to a significant disease burden. Specific histological characteristics are key to diagnosing microscopic colitis and to specify its subtypes collagenous colitis or lymphocytic colitis. Histological hallmarks of microscopic colitis are an increased inflammatory infiltrate in the lamina propria without significant crypt architectural distortion and intraepithelial lymphocytosis, which is generally more prominent in lymphocytic colitis. Next to these similarities, collagenous colitis is defined by a thickened collagen band underneath the surface epithelium, which is absent or only slightly present in lymphocytic colitis. Besides these two well defined subtypes of microscopic colitis, incomplete forms of microscopic colitis are acknowledged which give the same symptom burden and should be recognized and treated accordingly. Both clinical and histopathological research in the field of microscopic colitis is ongoing. Recent studies have focussed on where to take biopsies to best establish the diagnosis, the implications of supplementary stain usage and interobserver agreement. Furthermore, insight into the potential underlying pathophysiological mechanisms increases. This review aims to provide an overview of the condition of microscopic colitis, with a focus on diagnosis. In addition, it aims to highlight that the increasing incidence and associated significant disease burden imply that this condition is not so ‘microscopic’ at all.

Vascular pathology of the GI tract is prevalent worldwide. The etiologies associated with the histologic findings of “ischemic type injury” include common entities (such as atherosclerosis) as well as rare disease. This review article aims to describe the histologic findings of common and uncommon diseases resulting in vascular pathology, to help pathologists improve their diagnostic accuracy and guide clinicians in the management of these patients.