Rosai-Dorfman disease of the parotid gland: cytologic and histopathologic findings with immunohistochemical correlation.

Rosai-Dorfman disease is a rare histiocytic proliferative disorder of unknown origin and a distinct clinicopathologic entity also known as sinus histiocytosis with massive lymphadenopathy. The disease can involve extranodal tissues and rarely can present as salivary gland enlargement without significant lymphadenopathy. Involvement of the extranodal head and neck sites appears to be more common in patients with immunologic abnormalities. The disease was first described in 4 patients in 1969, and with later descriptions of more patients, the disease was established as a well-defined clinicopathologic entity. The characteristic pathologic feature of this disease is proliferation of distinctive histiocytic cells that demonstrate emperipolesis in the background of a mixed inflammatory infiltrate, consisting of moderately abundant plasma cells and lymphocytes. Fine-needle aspiration biopsy can be helpful in establishing the correct diagnosis, since surgical treatment is not necessary other than obtaining tissue for definitive diagnosis. We describe cytologic, histopathologic, and immunohistochemical features of a case of Rosai-Dorfman disease that involved a major salivary gland without significant lymphadenopathy in a 48-year-old patient with systemic lupus erythematosus. We also briefly discuss possible causes and pathogenesis and review the literature.

An analysis of factors that influence the ASCUS/SIL ratio of pathologists.

In pursuit of physician-specific performance data in cytology, we have been calculating the ASCUS/SIL (atypical squamous cells of undetermined significance/squamous intraepithelial lesion) ratio of cytopathologists (CPs) and providing confidential feedback every 6 months. At the same time, thin-layer technology was introduced as an alternative to conventional smears. Thus we analyzed factors that may influence the ASCUS/SIL ratio, particularly the effect of periodic feedback on outliers (defined by a professional benchmark). For 3 years, the mean ASCUS/SIL ratio for all CPs decreased significantly from 2.92 to 1.87. There was great variability in the mean ASCUS/SIL ratio among 12 CPs (range, 1.11-5.89). Of the 6 CPs who worked continuously during this time, 2 showed a statistically significant decrease in their ASCUS/SIL ratio, including the CP with the highest ratio; 1 showed a significant increase. The mean ASCUS/SIL ratio did not correlate well with years of CP experience or with individual annual case volume. The ASCUS/SIL ratio of some CPs can decrease significantly over time. Whether it was due to feedback or the introduction of thin-layer preparations could not be determined.