Calamine lotion: mimicking intramammary calcifications.

Detection of microcalcifications is important in detecting early breast cancer. We present a case of screening mammogram in which calamine lotion mimics intramammary calcifications.

Striatal neurons but not nigral dopaminergic neurons in neonatal primary cell culture express endogenous functional N-methyl-D-aspartate receptors.

Developmental expression of N-methyl-D-aspartate (NMDA) receptor subunits were determined and compared in striatal and nigral neurons in neonatal primary cell cultures. In striatal neurons, NR1, NR2A and NR2B mRNAs and immunoreactivity, and NR2D mRNA were found and the maximal levels of NR1 mRNA and immunoreactivity expression were found at 6 day-in-vitro (DIV). NMDA receptors found at this stage in striatal neurons are likely to contain NR1 plus NR2A, NR2B and NR2D subunits. In nigral neurons, NR1 and NR2B mRNAs and immunoreactivity, and NR2D mRNA were found and the maximal level of NR1 immunoreactivity expression was found at 10 DIV. Unlike striatal neurons, NMDA receptors found in nigral neurons are likely to contain NR1 plus NR2B and NR2D subunits only. NMDA-induced toxicity assays showed that striatal neurons were most susceptible to cell death at around 10 DIV but nigral neurons were not susceptible to NMDA-induced cell death at all stages. In addition, patch clamp analysis revealed that functional NMDA receptors could only be found in striatal neurons but not in nigral dopaminergic neurons in vitro. The present results indicate that striatal and nigral neurons are programmed to express distinct NMDA receptor subunits during their endogenous development in cell cultures. Despite dopaminergic neurons in culture display NMDA receptor subunits, functional NMDA receptors are not assembled. The present findings have demonstrated that dopaminergic neurons in vitro may behave very differently to their counterparts in vivo in terms of NMDA receptor-mediated responses. Our results also have implications in transplantations using dopaminergic neurons in vitro in treatments of Parkinson's disease.

Needle aspiration cytology of pancreatic cystic lesions.

Forty-two histologically confirmed cases of pancreatic cystic lesions with cytologic evaluation by needle aspiration biopsy (NAB) were reviewed. There were 21 inflammatory pseudocysts (IPC), nine mucinous cystic neoplasms (MCN), six microcystic serous adenomas (MSA), one macrocystic serous adenoma, and five papillary solid and cystic neoplasms (PSCN). Correct cytodiagnosis was made in all cases of IPC and MCN. The contents of IPCs were characterized by turbid or blood-tinged fluid containing cellular debris, numerous foamy macrophages, and other inflammatory cells. There were few or no epithelial lining cells. The aspirates from MCNs showed gelatinous mucoid material containing mucus-secreting cells that were present singly, in clusters, or in sheets. Depending on the individual case, benign or malignant columnar cells, or an admixture of these cells, were present in a mucinous background. The preoperative needle aspirates of five MSAs were acellular. In one case of MSA and in one example of macrocystic serous adenoma, small monolayered sheets of benign cubic epithelial cells were seen in the needle aspirates. Similar cytologic findings were noted in the materials obtained by intraoperative NAB performed under direct vision of the aforementioned five MSAs. Difficulties were encountered in typing three PSCNs that yielded in NAB cells resembling those of an islet cell tumor. They were diagnosed as low-grade neoplasms (PSCN vs. islet cell tumor). In two other patients, a cytodiagnosis of PSCN was correctly made as the NAB revealed monomorphic tumor cells wrapping around small capillary blood vessels.

Two unusual benign lesions of the neck masquerading as malignancy on fine-needle aspiration cytology.

Two cases of unusual benign tumors of the neck are described, both of which were initially misdiagnosed on cytology as carcinomas. Fine-needle aspiration findings in each case demonstrated a pleomorphic population of cells including bizarre multinucleated giant cells, the latter raising the false impression of malignancy. However, on review the cytological appearances of the tumors, a pleomorphic lipoma and a carotid body tumor, were characteristic. The correct diagnosis in each case would have been made or suggested if the pathologist had been familiar with the cytologic features characteristic of the lesion and the differential diagnosis of the head and neck tumors. In addition, the point is made that adequate clinical information is essential for the pathologist if all relevant conditions are not to be missed in the differential diagnosis.

Adrenal cortical cells mimicking small cell anaplastic carcinoma in a fine-needle aspirate.

Fine-needle aspiration of an adrenal mass was performed to rule out metastatic disease in a patient with a bronchogenic carcinoma. The aspiration was misinterpreted as metastatic small cell anaplastic carcinoma. Review of the aspirate by the authors revealed the atypical small cells to be aggregates of bare nuclei of benign adrenocortical cells. Interpretation of these bare nuclei in isolation and unfamiliarity with the aspiration cytology of the adrenal gland led to the initial misdiagnosis.

Cytology of head and neck tumors, liver, and pancreas.

The use of fine needle aspiration biopsy helps in reducing the number of thyroidectomies. Cytologic differentiation between cellular adenomas and well-differentiated follicular carcinomas is difficult, however; hence, both groups of lesions should be excised. Cytologic diagnosis of the common salivary gland tumors (ie, pleomorphic adenomas and Warthin's tumors) is accurate, but much experience is required for the cytodiagnosis of other tumor types. The majority of liver malignancies is metastatic in origin and poses no diagnostic problems. Pathologists also should be familiar with the cytology of hepatocellular carcinoma as the population of Asian immigrants in North America is increasing. Most of the pancreatic tumors are ductal adenocarcinomas, which can be diagnosed cytologically. Occasionally, atypical ductal epithelium in chronic pancreatitis may mimic malignancy. Cytodiagnosis of nonduct-cell neoplasms of the pancreas requires experience.