Fine needle aspiration of the thyroid: A cytohistologic correlation and study of discrepant cases

OBJECTIVE: Fine needle aspiration (FNA) is a reliable method in the initial assessment of thyroid nodules. The purpose of this study was to evaluate the causes for discordance between the interpretation on FNA and the pathologic findings in the resected thyroid. METHODS: A computer search of all thyroidectomy specimens with previous FNA from January 1998 to December 2001 was obtained from the files of the Lauren V. Ackerman laboratory of surgical pathology, Barnes-Jewish Hospital. Excluded from the study were those FNAs performed for suspected and confirmed metastatic disease to the thyroid as well as those cases unavailable for review. A total of 45 FNA cases were identified with cytologic and histologic discrepancies. RESULTS: Of the 1253 individual thyroid FNA performed during the study period, 255 patients (20%) subsequently had an open surgical procedure on the thyroid. Of those who underwent surgery, 196 cases (77%) were concordant, whereas 45 patients (18%) were discordant, and 14 cases were excluded due to unavailability of slides for review (for example, returned consult slides). The causes of the 45 discordant cases were: 20 cases (44%) were unsatisfactory for diagnosis, 14 cases (31%) were due to interpretation error (false positive), and 11 cases (24%) were due to sampling error (false negative). CONCLUSIONS: The most common causes of our discrepant cases are those whose FNA diagnosis was interpreted as unsatisfactory for diagnosis, in 20 (7.8%) of 255 surgical cases. The false negative rate due to sampling error in 11 (4%) of 255 cases was mainly due to the presence of microscopic papillary thyroid carcinoma (PTC); the false positive rate was due to interpretation error in 14 (6%) of 255 cases, and those were explained by the occurrence of overlapping cytologic features among adenomatous nodules, follicular neoplasms, the follicular variant of PTC, and Hashimoto\u27s thyroiditis

EMPIRICAL STUDY OF THE PROBABILITY OF DEFAULT IN CASE OF ROMANIAN COMPANIES LISTED ON STOCK EXCHANGE

The importance of estimation of a firm's probability of default increased significantly during the economic and financial crisis for financial institutions, which can be explained by the fact that the share of nonperforming loans increased in this period. The probability of default can be estimated with structural models, which have on base the methodology developed by Merton (1974), methodology used by Moody's Corporation (known as KMV Merton model). The aim of this study is to estimate the probability of default of companies listed on Bucharest Stock Exchange using this methodology. This approach was widely used in the literature by many researchers (i.e., Kealhofer and Kurbat (2000), Crosbie and Bohn (2002), Duffie and Wang (2004), Bharath and Shumway (2004, 2008)). In Romania this methodology was empirically tested by Codirlaşu (2007), who estimated using Merton's methodology the probability of default of companies listed on the Bucharest Stock Exchange, respectively by Bobircă et al. (2008), where the probabilities of default were estimated in case of 42 companies listed on the Bucharest Stock Exchange for 2000-2008 time period. In this paper we used Merton's model, which assumes that a company defaults if the value of its assets is less than the promised dept repayment at time T. The process of estimating the probability of default starts from the following firm specific variables: the market value of the firm's assets, the share prices, the value of the liabilities and the risk-free rate. The analyzed period is 2003-2010, containing the economic and financial crisis period, too. Analyzing the financial statements of the companies listed on the Bucharest Stock Exchange, we determined the input parameters of the model and calculated the quarterly probabilities of default of each analyzed company. According to our results the probabilities of default have a reduced value in the majority of the cases.Merton model, probability of default, credit risk, structural models, companies listed on the stock exchange.

Merkel cell carcinoma and chronic lymphocytic leukemia (collision tumor) of the arm: a diagnosis by fine-needle aspiration biopsy.

Simultaneous involvement of the same anatomical site by two different primary malignant tumors is rare. Cases of hematopoietic malignancies associated with breast and skin neoplasms have been described. The association of chronic lymphocytic leukemia (CLL) and Merkel cell carcinoma (MCC) has been established, although the cause for this association is still unclear. There are reports of MCC metastatic to lymph nodes involved by CLL. We report the case of a 57-year-old man with history of CLL with concurrent involvement of the arm by CLL and MCC diagnosed on fine-needle aspiration biopsy (FNA). To our knowledge, this is the first reported case of such tumors colliding in a nonlymphoid site, diagnosed by FNA in the English literature

Cytologic diagnosis of intraocular lymphoma in vitreous aspirates.

OBJECTIVE: To evaluate the cytologic findings of vitreous fluids with atypical, suspicious for malignancy or malignant lymphoid cells to assess cytologic parameters that may help in reaching the diagnosis of intraoclular lymphoma. STUDY DESIGN: Vitreous aspirates with a malignant, suspicious for malignancy or atypical lymphoid population were identified from the files of Barnes-Jewish Hospital during the previous 11 years. Cytologic preparations were reviewed. Pertinent clinical information was obtained from medical records. RESULTS: Thirteen vitreous aspirates from 12 patients were included. The chief complaints included floaters, blurred vision and decreased visual aculity. Bilateral ocular involvement was present in 8 (67%) patients. Three patients had a history of an extraocular lymphoid malignancy. All patients underwent pars plana vitrectomy and collection of the vitreous aspirate. Cytologic diagnoses included: malignant lymphoma (9 of 13), suspicious for malignant lymphoma (3 of 13) and atypical lymphoid population (1 of 13). Most samples had high cellularity (11 of 13) and necrosis (9 of 13). Abnormal lymphoid cells were large (2-4 times the size of a lymphocyte) and had a high nuclear/cytoplasmic ratio, prominent nucleoli, irregular nuclear contours and a fine to coarse chromatin pattern. All cases with malignant cytology had abundant abnormal lymphoid cells; inconclusive cases had few. Immunocytochemistry for CD20 and CD45RO was performed on 9 of 13 samples and was conclusive in 6 of 9. CONCLUSION: Cytologic analysis of vitreous aspirates can be useful in diagnosing intraocular involvement by malignant lymphoma. Sparse cellularity is the main factor leading to inconclusive diagnoses. Immunostaining can be useful in confirming the lymphoid nature of the malignant cells

An IgM lambda antibody to Escherichia coli produces false-positive results in multiple immunometric assays.

BACKGROUND: Interferences in immunometric assays as a result of human anti-immunoglobulin antibodies frequently have been described in the literature. The etiology of these interfering antibodies is usually not known but has been associated with rheumatoid factors in some assays. It is known that microorganisms in experimental settings can induce anti-immunoglobulin antibodies. METHODS: Following Escherichia coli septicemia, a 56-year-old male patient had increased immunoassay results for cardiac troponin I, thyrotropin, human chorionic gonadotropin, alpha-fetoprotein, and CA-125 that were consistent with myocardial infarction, hyperthyroidism, and pregnancy, and suggestive of an occult neoplasm such as hepatic or ovarian cancer. None of these diagnoses were consistent with the rest of his medical exam. In addition, the patient had a restricted IgM lambda paraprotein by immunofixation. Plasma from the patient was incubated with Sepharose-conjugated protein A, irrelevant murine monoclonal antibodies, and formalin-killed E. coli organisms from his infection to determine whether these immunoassay values were falsely increased. RESULTS: Incubation of the patient\u27s plasma with irrelevant murine monoclonal antibodies or the E. coli organism produced normal immunoassay values and removed the IgM lambda paraprotein. CONCLUSIONS: The patient produced a very restricted IgM lambda antibody response to the E. coli infection that had anti-immunoglobulin activity and caused falsely increased values in numerous immunometric assays. Microorganism-induced anti-immunoglobulin antibodies are discussed in the context of this patient