A Single Institutional Experience With the Paris System for Reporting Urinary Cytology: Correlation of Cytology and Histology in 194 Cases.

Objectives: The Paris System for Reporting Urinary Cytology (TPS) is designed to standardize the criteria and terminology used in urinary tract cytology reporting. The aim of this study was to evaluate the impact of implementing TPS and to analyze the correlation with follow-up biopsies in order to assess its reproducibility.

Methods: Urinary tract cytology specimens with follow-up biopsies over a 2-year period were reviewed and reclassified according to TPS criteria.

Differentiating benign from malignant bone marrow B-cell lymphoid aggregates: a statistical analysis of distinguishing features.

Context: Lymphoid aggregates are seen in a minority of bone marrow biopsy specimens, and when present, their neoplastic nature is often apparent by morphologic evaluation. However, the distinction between benign and malignant aggregates can be a diagnostic challenge when there are multiple aggregates with no documented history of lymphoma.

Objective: To aid in the distinction between benign and malignant B-cell lymphoid aggregates.

Benign lymphoid aggregates in the bone marrow: distribution patterns of B and T lymphocytes.

Benign lymphoid aggregates are seen in only a minority of bone marrow specimens, but their distinction from non-Hodgkin lymphoma, particularly B-cell lymphomas, can represent a diagnostic challenge. Although criteria have been proposed to help distinguish between benign and malignant aggregates, a detailed description of the distribution patterns of B and T lymphocytes within benign lymphoid aggregates has not been investigated. One hundred thirty-seven cases of bone marrow specimens containing benign aggregates were studied with a panel of immunostains.

Colorectal stents orient specimens and induce artifacts that mimic Crohn disease.

Colorectal malignancies may be stented to alleviate obstruction. The stent is a polarized and braided network of metallic wires. Pathology associated with colorectal stents is yet to be described.