Simultaneous immunostaining with anti-S100P and anti-SV40 antibodies revealed the origin of BK virus-infected decoy cells in voided urine samples.

BACKGROUND: Methods for determining the origin of BK virus (BKV)-infected cells (decoy cells) in clinical urine samples have not been established although they could enhance the diagnosis of BKV infection in immunocompromised patients. METHODS: We performed simultaneous immunostaining with anti-S100P (a urothelial marker) and anti-SV40 antibodies in 66 clinical urine samples exhibiting SV40 positivity and a decoy-cell appearance on Papanicolaou staining. The clinical voided urine samples included seven cases of renal transplantation, 47 cases of cancer therapy and 12 cases of non-neoplastic disease. SurePath(™) liquid-based cytology was used for the urine samples. RESULTS: BKV-infected cells were categorized as SV40(+)/S100P(+) and SV40 (+)/S100p(-). SV40(+)/S100P(-) cells were found in 55 cases (83.4%); nine cases (13.6%) carried both SV40(+)/S100P(-) and SV40(+)/S100P(+) cells. The former were identified as BKV infection in renal tubules and the latter in both the renal tubules and urothelial epithelia. The remaining two cases (3.0%) had only SV40(+)/S100P(+) cells of urothelial origin. CONCLUSION: Simultaneous immunostaining with anti-S100P and anti-SV40 is a useful method for determining the origin of BKV-infected cells in clinical urine samples from immunocompromised patients such as renal transplantation recipients.

Giant lamellar bodies in pulmonary MALT lymphoma. A case report.

BACKGROUND: Giant lamellar bodies are laminated, scroll-like whorls seen within alveolar spaces and have been occasionally observed in sclerosing hemangioma of the lung. However, to the best of our knowledge, the cytologic findings of giant lamellar bodies have not been reported. We describe cytologic findings of giant lamellar bodies associated with pulmonary mucosa-associated lymphoid tissue (MALT) lymphoma. CASE: A 72-year-old male had a pulmonary mass measuring 2.0 x 1.4 x 1.5 cm. Cytologic smears imprinted from a cut surface of the resected mass revealed a large number of concentrically laminated structures, giant lamellar bodies, measuring 15-40 microns in diameter. Necrotic cellular remnants were occasionally observed in the center of the structures. In the background, small to medium-sized lymphoid cells and plasmacytoid cells were observed. Histologic diagnosis of the tumor was IgG, kappa type, MALT lymphoma. An aggregate of giant lamellar bodies was observed within entrapped, dilated alveolar spaces lined with hypertrophied, type II pneumocytes. Immunohistochemically, the giant lamellar bodies were positive for KL-6. CONCLUSION: Giant lamellar bodies may be derived from surfactant and necrotic type II pneumocytes and may be observed cytologically in cases of pulmonary MALT lymphoma.

Scrape cytology of elastofibroma. Report of a case with diagnostic cytologic features.

BACKGROUND: Elastofibroma is a benign, soft tissue tumor that occurs most frequently in the subscapular area in elderly people. To the best of our knowledge, in only two cases has the cytology been reported. The aim of this report is to describe the characteristic cytologic findings of elastofibroma and to discuss the usefulness of elastin stain in scrape smears. CASE: A 72-year-old female had bilateral masses in the lower subscapular area. Scrape smears from a cut surface of the resected masses revealed abundant, "wormlike" or "braidlike" material with central cores with Papanicolaou stain in an intraoperative consultation. Various-sized, petaloid or crystalloid globules were also present. Those elastic fibers were strongly positive for elastin stain in cytologic preparations. CONCLUSION: Elastofibroma can be diagnosed cytologically, and elastin-stained, scrape cytologic preparation is especially useful in such a case.