Clinicocytopathologic correlation in an atypical presentation of lymphadenopathy with review of literature.

OBJECTIVES: To present a clinicocytopathologic correlation of an atypical case of cat scratch disease (CSD) involving retroperitoneal lymph nodes, with emphasis on communication between service teams for managing lymphadenopathy of unknown origin. We consider clinical and cytologic differential diagnoses and review the literature on atypical cases of CSD, with emphasis on abdominal presentation and cytologic findings. METHODS: Clinical services met with the cytology service to review clinical and pathologic features. Literature was reviewed via PubMed search (Harbor-UCLA subscriptions). Immunohistochemistry and Steiner silver stains were performed by Harbor-UCLA Department of Pathology. Enzyme-linked immunosorbent assay IgG and IgM Bartonella henselae titers were carried out by Quest Nichols Institute. RESULTS: Fine-needle aspirate Diff-Quik and Papanicolaou smears and H&E-stained cell block showed abundant histiocytes, monocytoid B cells, and numerous neutrophils associated with necrosis corresponding to a late stage of CSD infection. Silver stain was positive for clumps of pleomorphic organisms. IgM and IgG antibody titers were elevated. CONCLUSIONS: The cytologic findings of CSD in an atypical abdominal presentation are similar to those of a classic presentation. Laboratory workup for atypical CSD should include at least two other modalities aside from cytomorphologic features. Close clinical and cytologic correlation avoided potentially unnecessary and harmful surgery and enabled timely treatment.

Cytomorphological features of epithelioid hemangioendothelioma in ascitic fluid with radiological, clinical and histopathological correlations.

BACKGROUND: Epithelioid hemangioendothelioma (EHE) is an uncommon vascular soft-tissue tumor. Five cases of EHE in body fluids have been documented in the literature, all of them occurring in pleural effusions. This is the first description of cytomorphological features of EHE cells in ascitic fluid, accompanied by corresponding histopathological findings, clinical, and radiological data. CASE REPORT: Our patient presented with several liver masses, peritoneal involvement, bilateral pleural effusions, and massive ascites. EHE was suspected on cytological examination of the ascitic fluid and was confirmed by immunohistochemical studies. Simultaneously, a liver mass was identified and diagnosed on biopsy as EHE, affording accurate histopathological correlation. Cytologically, EHE cells appear relatively bland, often obscured by reactive mesothelial cells, and dispersed singly or clustered. They often possess intracytoplasmic vacuoles, referred to as 'blister' or 'signet ring' cells. High-power examination shows slightly misshapen mildly hyperchromatic nuclei with inconspicuous nucleoli. Immunohistochemically, EHE cells express strong positivity with vascular markers (CD31, CD34 and factor VIII). They are nonreactive with mesothelial markers (calretinin and WT-1). CONCLUSION: Recognition of the possibility of EHE cells in fluid by morphology should prompt proper immunohistochemical work-up to ensure an accurate diagnosis and timely patient management.