Evaluation of dual immunohistochemistry and chromogenic in situ hybridization for HER2 on a single section.

The evaluation of HER2 status in invasive breast carcinoma can be performed by multiple methods. We assessed the feasibility of performing 2 of these, chromogenic in situ hybridization (CISH) and immunohistochemical staining, on single tissue sections of breast carcinoma. During assay development, sequential performance of immunohistochemical staining after CISH resulted in weaker HER2 expression than that obtained when immunohistochemical staining was performed alone; this was ameliorated by increased antibody incubation time. Performance of both techniques in a combined/hybrid protocol resulted in HER2 protein expression and gene signals identical to those produced by the individual techniques performed alone. Prospective validation of these dual staining protocols in 31 cases of breast carcinoma resulted in 100% concordance with results of CISH when performed alone, but was still associated with a reduced immunohistochemical signal in some cases. Although further testing is needed, we conclude that performance of both immunohistochemical staining and CISH on a single section is possible and could allow for direct "cell-by-cell" comparison of HER2 signals and potentially offer a more economical and real-time method for ongoing validation of HER2 testing.

Immunohistochemical expression of p16 and Ki-67 correlates with degree of anal intraepithelial neoplasia.

Anal intraepithelial neoplasia (AIN) is a human papilloma virus related lesion. It has been shown that infection with high-risk human papilloma virus results in up-regulation of p16 and increased cellular proliferation. The objective of this study is to correlate p16 expression and cellular proliferation measured by Ki-67 staining with the degree of dysplasia in the anal canal and to determine the efficacy of these markers in diagnosing high-grade AIN. Seventy-five anal specimens from 55 patients (37 men; 18 women; mean age: 48 y; median: 44 y; range 25 to 96 y) were studied including 35 normal/reactive lesions, 23 low-grade AIN (AIN I and condyloma), and 17 high-grade AIN (AIN II and III). Immunostaining for p16 and Ki-67 was performed. Expression of p16 in AIN correlated with that of Ki-67 (P<0.001). High-grade AIN often demonstrated p16 staining in more than one-third of the thickness of the epithelium in a diffuse/continuous fashion. p16 expression in low-grade AIN was often restricted to the lower 1/3 of the epithelium and/or was focal and discontinuous. The expression of both p16 and Ki-67 correlated with the degree of dysplasia (P<0.01). When positive p16 staining was defined as the presence of diffuse/continuous staining in more than one-third of the thickness of epithelium, the sensitivity, specificity, and accuracy of p16 as a marker for diagnosing high-grade AIN were 76%, 86%, and 84%, respectively. When positive Ki-67 staining was defined as the presence of nuclear staining in more than 25% of the cells in more than one-third of the thickness of epithelium, the sensitivity, specificity, and accuracy of Ki-67 as a marker for diagnosing high-grade AIN were 71%, 84%, and 83% respectively. Both p16 and Ki-67 are reliable markers for diagnosing high-grade AIN.

Medical decision-making in the nursing home: a comparison of physician and nurse perspectives.

The purpose of this study is to clarify the perspectives of physicians and nurses in the medical decision-making process at the time of status change events in nursing home residents. The decision-making processes studied involved 28 cognitively impaired nursing home residents in a large suburban nursing home. In interviews, the authors ascertained the personal opinions of physicians and the nurses related to the status change event and the decision-making process using the Medical Decision-Making During a Status Change Event Questionnaire. Nurses reported a greater degree of familiarity with the family's and resident's wishes than did physicians. Physicians reported considering more treatment options and choosing more treatments for residents than nurses. Both physicians and nurses reported that the physicians had a major role in decision-making and that nurses did not, yet the gap in reported roles was greater based on physicians' reports in comparison to nurse reports. In a third of the reported cases, physicians and nurses disagreed about whether advance directives had been followed. These findings reflect a division of roles and perspectives of nurses versus physicians in the medical decision-making process. This study demonstrates the ability of the questionnaire to reveal several key differences in perceptions of care. This information could be useful in developing forums for communication among the professionals to enhance mutual understanding.

Use of mesothelin as a marker for mesothelial cells in cytologic specimens.

Immunocytochemistry is often employed for the distinction between mesothelial cells and adenocarcinoma. Mesothelin has recently been reported to be expressed in reactive mesothelial cells and epithelioid mesotheliomas. The objective of this study is to determine the utility of mesothelin as marker for mesothelial cells in cytologic preparations. Thirty cell blocks were retrieved from the archives and immunostained with monoclonal antibody directed against mesothelin and calretinin. Heat-induced epitope retrieval technique was employed, and the immunostaining was accomplished using an automated stainer. These tissue blocks were from 35 patients (17 females and 18 males) with a median age of 64 years. Nine were benign effusions, 11 mesotheliomas, and 18 metastatic adenocarcinomas. The presence of any immunoreactivity, irrespective of level of intensity or percentage of cells, was considered positive for mesothelin expression. Follow up included correlation with pathology materials obtained at surgery and review of medical records. Mesothelin staining was positive in 7/9 benign cases, 8/11 mesotheliomas, and 8/18 adenocarcinomas. The difference of mesothelin expression between mesothelial cells and adenocarcinoma was statistically significant. For calretinin, all cases, except 2 malignant mesotheliomas and 3 adenocarcinomas, showed positive staining with calretinin. As a marker for mesothelial cells, the sensitivity and specificity of mesothelin were 73% and 55%, respectively, and the sensitivity and specificity of calretinin were 95% and 86%, respectively. Therefore, mesothelin is not a sensitive or a specific marker for mesothelial cells in cytologic specimens when compared with calretinin.

Which signs and symptoms warrant involvement of medical staff? The definition and identification of status-change events in the nursing home.

In this article, the authors clarify the concept of status-change events (a significant clinical change that calls for medical follow-up by a physician) by providing preliminary descriptions of these events, and attempting to differentiate them from incidents that did not qualify as status-change events. Participants were residents from a large, nonprofit nursing home. Data were collected about the source of information, the nature of the incident, whether it qualified as a status-change event, and the reason (if any) for disqualification. The most common incidents involved in status-change events were troubled breathing, aspiration, fracture, and hypotension. The most common incidents that did not qualify as status-change events were continuing pneumonia, bruises, lacerations, disorientation, and blood pressure abnormalities. A wide range of physical ailments characterized both status-change events and incidents that did not qualify as status-change events. The main reason an incident did not qualify was because it did not warrant contacting the physician. The nature of the incident is insufficient in itself to determine whether the incident qualifies as a status-change event. The process for identifying and analyzing status-change events in the nursing home requires several steps and much persistence.