Large granular lymphocytic leukemias (LGLLs), including T-cell LGLL and natural kill (NK)-cell LGLL variants, are rare lymphoproliferative disorders characterized by the chronic proliferation of cytotoxic lymphocytes. Despite recent advancements, challenges remain in distinguishing these entities from one another and from related disorders, such as T-cell prolymphocytic leukemia, adult T-cell leukemia/lymphoma, Sézary syndrome, and aggressive NK-cell leukemia, owing to overlapping clinical and morphologic features. This article aims to review the role of molecular and immunophenotypic markers in guiding diagnosis and prognosis of LGLLs, with brief review of their clinical and morphologic features by synthesizing current advances in molecular pathogenesis, immunophenotypic profiling, and updated World Health Organization (WHO) classification criteria in order to enhance diagnostic precision, improve prognostic assessment, and inform personalized treatment strategies for these challenging disorders.

Literature was searched through Pubmed and the recently published 5th WHO classification criteria. Articles were reviewed and analyzed with emphasis on recent molecular and cytogenetic insights.

A total of 106 publications were reviewed, and the recent molecular insights—focusing on those concerning STAT3 mutations in T-cell LGLL and TET2 mutations in NK-cell LGLL which have refined diagnostic frameworks, though gaps persist in understanding their clinical relevance and variability.

By providing a comparative analysis of large granular lymphocytic leukemias and their differential diagnoses in cooperation of the current advances in molecular pathogenesis, immunophenotypic profiling, and updated WHO classification criteria, this work aimed to enhance diagnostic precision, improve prognostic assessment, and inform personalized treatment strategies for these challenging LGLLs.

Leishmaniasis is a systemic parasitic disease that can affect unusual sites such as the lungs.

We report a case of a 45-year-old male with human immunodeficiency virus infection who presented with abdominal pain and vomiting. Imaging studies revealed minimal bilateral ground-glass opacities in the lungs, hepatosplenomegaly, and diffuse lymphadenopathy. A bronchoscopy with bronchoalveolar lavage cytology evaluation showed abundant macrophages containing numerous intracellular organisms with characteristic dot-like kinetoplasts, confirming the diagnosis of Leishmaniasis. Special stains for other infections were negative.

This case highlights the value of bronchoalveolar lavage cytology in diagnosing non-neoplastic lung pathologies, including parasitic infections like Leishmaniasis, thereby enabling prompt and targeted treatment.

Hermansky-Pudlak syndrome (HPS) is a rare, autosomal recessive disorder predominantly affecting individuals of Puerto Rican descent. It is characterized by oculocutaneous albinism, platelet storage pool deficiency, and lysosomal ceroid accumulation in tissues. Lysosomal dysfunction has been shown to be associated with pulmonary fibrosis and granulomatous colitis in HPS patients, accounting for a significant portion of morbidity and mortality in this population. Clinical and endoscopic gastrointestinal manifestations in HPS patients are similar to those of active Crohn’s disease, including abdominal pain, bleeding, fissures, fistulas, and perianal involvement. Histology reveals granulomatous colitis that can be difficult to distinguish from Crohn’s disease. Identifying distinct morphologic features from Crohn’s disease is crucial for the diagnosis of HPS. Here, we present a case of a 27-year-old male with a history of HPS and refractory granulomatous colitis with severe perianal disease, who underwent total proctocolectomy and perianal excision. The unique, distinguishing morphologic features from Crohn’s disease in this case are: 1) grossly diffuse ulceration in the ano-rectum and cecum, 2) ulcerative and granulomatous inflammation predominantly involving the mucosa and submucosa of the colon, and 3) accumulation of ceroid pigment in the histiocytes of the lamina propria throughout the entire gastrointestinal tract. Immunohistochemical stains for CD3 and FoxP3-positive T cells in the granulomatous colitis were further analyzed. Thus, we fully document the extent of disease involvement and morphologic features in this patient and extensively discuss the similarities and differences between HPS and Crohn’s disease.

The International Academy of Cytology Yokohama System for Reporting Breast Fine-Needle Aspiration Biopsy Cytology was developed by a group of expert cytopathologists and clinicians in the breast field. Five categories are defined to stratify breast lesions by their risks of malignancy and managed accordingly. Clinical and radiologic information (triple test) are critical for further management. Ultrasound guidance, and rapid on-site evaluation are valuable for improving the rate of definitive diagnosis. Ancillary studies can be tested on cytologic samples to provide prognostic, predictive information as well as diagnostic clues. Based on many published studies in different institutions worldwide, the implementation of the system appears to have been successful. However, further studies are important for improvements and modifications to the current system.

Coagulation testing is essential for the diagnosis and management of a variety of hemophilia, thrombophilia, and complicated coagulopathies. This is often used prior to surgery, or as a follow-up investigation for patients being scrutinized for bleeding diathesis, or to monitor the anticoagulant therapy. When the results are abnormal, a mixing study is often the initial reflexive test that can provide valuable information to conclude the assessment, or help guide further investigations. If the mixing “corrects” the test results, a factor deficiency would be suspected. Otherwise, the presence of an inhibitor would be more likely. However, defining “correction” remains difficult and controversial. There are several available methods to determine whether a result is corrected. Each method has its own advantages and limitations. It is noteworthy that although a complete correction can be interpreted as factor deficiency, a partial or incomplete correction does not rule out the coexistence of factor deficiency and the presence of a coagulation inhibitor. Hence, caution should be taken in interpreting mixing study results for patients who are taking direct-acting oral anticoagulants. Ideally, mixing study results are interpreted in correlation with the patient’s clinical history, including bleeding or thrombosis history, and the use of anticoagulants. This review aimed to evaluate the methods used in interpreting coagulation mixing studies and to discuss their respective advantages and limitations

The Paris System for Reporting Urinary Cytology (TPS 1.0, published in 2016) is the first standardized, evidence-based reporting system established as an international reporting system for urine specimens after the International Congress of Cytology in Paris. Its primary purpose is to reduce the rate of unnecessary indeterminate diagnoses but maintain the excellent performance of urine cytology, in detecting high-grade urothelial carcinoma. The reporting system comprises six diagnostic categories, as well as each category’s diagnostic criteria, estimated risk of malignancy, and management recommendations. After six years, TPS 2.0 was applied in 2022 upon the unfolding of new data. TPS 2.0 clarifies the diagnosis categories and updates the risk of malignancy in each category and developments of molecular tests. This review provides an updated summary of TPS 2.0. Some diagnostic pitfalls and molecular tests were also discussed.