Fine needle aspiration cytology of the thyroid: a cytohistologic study with evaluation of discordant cases.

OBJECTIVE: To analyze the diagnostic efficacy of fine needle aspiration cytology (FNAC) in the initial evaluation of thyroid nodules, with special emphasis on discrepant cytologic diagnoses. STUDY DESIGN: A total of 192 thyroid fine needle aspirates with subsequent histopathologic follow-up were analyzed. The cytologic diagnoses were divided into 4 categories: positive for malignancy, negative for malignancy, indeterminate for diagnosis and nondiagnostic. The detailed cytologic features were studied along with histopathology sections in all these cases by 2 observers (S.J. and P.D) independently. RESULTS: Cytohistologic correlation was seen in 78.1% of cases and discordance in 21.9%. Indeterminate diagnoses accounted for 15.1% of cases. The majority of these were "follicular neoplasms." The overall sensitivity was 84.44% and specificity 99.11 %. A false positive diagnosis was made in 1 case (0.5%), proven a follicular adenoma on histopathologic examination. A false negative diagnosis was seen in 3.6% of cases. These were cases of papillary microcarcinoma. CONCLUSION: FNAC is a safe, sensitive and specific technique in the initial evaluation of thyroid nodules. A correct cytologic diagnosis can be achieved in a majority of cases, thus obviating the need for a second surgical intervention. A careful and diligent search for various cytologic features and accurate sampling can help in reducing the number of indeterminate, false positive and false negative diagnoses.

Clinical characteristics and pathological classification of non-Hodgkin's lymphoma in Kuwait. Results of a collaborative study with the International Lymphoma Study Group (ILSG).

Kuwait was chosen by the International Lymphoma Study Group (ILSG) as one of the sites attending in the project on "Clinical characteristics and pathological classification of non Hodgkin's lymphoma (NHL) in the developing countries". The Kuwait study involved 206 cases of NHL, diagnosed, staged and treated in the Kuwait Cancer Control Center (KCCC). All cases were reviewed and reclassified independently by the pathologists of KCCC and the International Lymphoma Study Group (ISLG) using the latest World Health Organization (WHO) classification of neoplastic disease of the hematopoietic and lymphoid tissues. Immunophenotyping as to B- or T-cell was documented in all cases. Three main pathological entities (diffuse large B-cell lymphoma, follicular lymphoma, peripheral T-cell lymphoma) were identified and studied thoroughly. The intense cooperation between experts of the ISLG and pathologists of the KCCC proved that the WHO classification was fully reproducible in Kuwait. The high incidence of extranodal lymphomas (53%) observed in the KCCC may not be due to special ethnic or environmental conditions in Kuwait but rather be due to a selection of patients coming to our center.

Loss of heterozygosity and microsatellite instability in male breast cancer.

Male breast cancer is a relatively rare disease that represents about 1% of all male malignancies. Its genetic basis has received little attention. Allelic imbalance, reflected by change in microsatellite repeat number (MSI) or loss of heterozygosity (LOH), is thought to play an important role in carcinogenesis. In this study we have examined DNA extracted from paraffin tissue from 15 patients treated for male breast cancer, for evidence of such abnormalities, at 20 different loci across the genome. Polymerase chain reaction amplified products of normal and tumor DNA pairs were compared by electrophoresis on Spreadex gels. MSI was detected in 5 patients; at a single site in 2 cases and at 3, 7 and 9 sites in another 3 cases. LOH was seen in 8 cases (53%); at more than one site in 4 of these. Two patients had allelic variation at 56 and 62% of assessable sites. The most unstable loci were D2S441 (33%) and D13S325 (27%). These observations indicate that replication errors and allelic loss characterise male breast cancer tissue in much the same way as they do in women. More studies will be needed to establish whether these are random lesions or whether there are specifically affected sites that occur in both male and female breast cancer.

Intrathyroidal parathyroid carcinoma: a case report with clinical and histological findings.

The chance of an intrathyroidal occurrence of a parathyroid gland is about 1-3%. Among the causes of hyperparathyroidism, parathyroid cases occur in less than 1% of patients. Here we present the case of a 63 year old Saudi female suffering from an intrathyroidal parathyroid carcinoma. The suspicion coming from the clinical investigations that the removed tumor tissue may be a parathyroid carcinoma could be confirmed by histology. Additionally non-radioactive in situ hybridization to localize mRNA transcripts for Cyclin D1 and immunohistochemical localization of Cyclin D1 was performed. Although parathyroid adenoma and carcinoma have disparate natural history, it can be difficult to differentiate between the two entities. Clinical presentation, operative findings may raise suspicion, but may not be conclusive especially if there is no evidence of invasion or metastasis, especially if the gland was intrathyroidal.

Rosai-Dorfman disease presenting as bilateral eyelid swellings.

OBJECTIVE: To report a case of sinus histiocytosis with massive lymphadenopathy (Rosai-Dorfman disease) in an extranodal site with unusual presentation. CASE PRESENTATION: A 19-year-old girl presented with bilateral upper eyelid swellings of 2 years duration due to tumor. The masses were excised and sent for histopathological examination. Microscopic examination revealed similar features in both masses in the form of a collection of large histiocytic cells showing emperipolesis (lymphocytophagocytosis). The histiocytic cells stained positively with S-100 protein and CD68. The background comprised small lymphocytes and plasma cells. Based on the overall features a diagnosis of sinus histiocytosis with massive lymphadenopathy or Rosai-Dorfman disease was made. CONCLUSION: The present case highlights one of the forms in which extranodal Rosai-Dorfman disease can manifest itself. It is important to keep this differential diagnosis in mind whenever such histopathological features are encountered.