Asymptomatic expectoration of surgical staples complicating lung volume reduction surgery.

Lung volume reduction surgery (LVRS) has recently been introduced as a palliative treatment for patients with severe emphysema. The most common postoperative complication is persistent air leak requiring prolonged tube thoracostomy. We describe a unique case of a patient with severe emphysema who underwent LVRS and presented, about a year later, with the repeated expectoration of surgical staples.

Mixed columnar cell and tall cell variant of papillary carcinoma of thyroid: a case report and review of the literature.

Columnar cell and tall cell carcinomas are newly described variants of papillary thyroid carcinoma associated with aggressive clinical behaviour. Although several cases of tall cell and columnar cell variants have been reported, only a single detailed case report of a mixed tall cell and columnar cell variant has been described in the English-language literature. We report another such composite tumour with predominant columna cell features in an elderly female. The tumour showed extrathyroidal extension with intraluminal superior thyroid vein invasion and lymph node metastasis. DNA ploidy analysis showed a diploid DNA content with no increase of S-phase fraction. Immunohistochemistry showed focal positivity for p53 and Ki-67 at the infiltrating margins of the tumour and diffuse positivity for proliferating cell nuclear antigen. The adverse clinical course warrants aggressive treatment and careful follow-up.

Fine needle aspiration cytology of mixed tall and columnar cell papillary carcinoma of the thyroid. A case report.

BACKGROUND: We report the first case of a composite tumor (tall cell and columnar cell variants) of papillary thyroid carcinoma (PTC) diagnosed by fine needle aspiration. It is important to differentiate these uncommon aggressive variants from the usual indolent papillary carcinomas. CASE: Fine needle aspiration cytology was obtained from a rare composite tumor of tall cell and columnar cell variants of papillary thyroid carcinoma. The smears showed a cellular aspirate with scattered single tumor cells and several tissue fragments arranged in a papillary pattern. The tumor cells had abundant nuclear grooves and intranuclear pseudoinclusions. Several of the fragments showed columnar cells with nuclear pseudostratification, and a few clusters displayed tall columnar cells with basal nuclei and abundant cytoplasm. A rare cluster exhibited composite features of tall cell and columnar cell variants. CONCLUSION: Columnar cell and tall cell variants of PTC manifest aggressive clinical behavior. The differential diagnosis of columnar cell variant includes medullary carcinoma of thyroid and metastatic adenocarcinoma. Immunohistochemical stains for calcitonin and thyroglobulin play an important role in difficult cases. The tall cell variant needs to be differentiated from Hürthle cell papillary neoplasm of thyroid, which displays prominent nucleoli and lacks the characteristic nuclear features of PTC. The preoperative diagnosis of these aggressive variants' is important in planning the most appropriate type of treatment.

Interferon-alpha generation in mice responding to challenge with UV-inactivated herpes simplex virus.

In humans with advanced human immunodeficiency virus (HIV) infection, an interferon-alpha (IFN-alpha) response by a specialized blood mononuclear cell to herpes simplex virus (HSV) in vitro is associated with resistance to opportunistic infections. A cell type of unknown lineage, designated the natural IFN-producing cell (NIPC), has been identified preliminarily as the source of these IFNs and may have a role in other host defense functions. Earlier studies suggested the existence of analogous HSV-responsive cell populations in mice. The role specifically of IFN-alpha in the murine system, however, has not been characterized. Using IFN bioassay and neutralization with antisera against Type I IFNs and IFN-beta, we have defined the types and sources of IFNs produced by mice in response to in vivo and in vitro challenge with UV-inactivated HSV. After intraperitoneal inoculation with HSV, BALB/c and C57Bl/6 strains produced characteristically different levels of serum IFNs that appeared principally to be IFN-alpha. The response of mononuclear cells from these mice differed from that of the intact mouse. Isolated cells from bone marrow and spleen released detectable IFNs much later than did whole animals, and the IFNs produced by marrow, spleen, and peritoneal cells were usually neutralized by the anti-IFN-beta. Only bone marrow cells produced detectable amounts of IFN-alpha. Both intact mice and their cells became refractory to restimulation with similar kinetics.

Merkel cell carcinoma arising in the oral mucosa.

This is the first reported case of a Merkel cell carcinoma arising in the oral mucosa. The tumor occurred in a 53-year-old white man, and it originated in the right mucobuccal fold. The Merkel cell origin was confirmed by electron microscopic and immunohistochemical studies.