Galectin-3 and CD44v6 positivity by RT-PCR method in fine needle aspirates of benign thyroid lesions.

OBJECTIVE: To investigate whether the presence of macrophages and Hürthle cells (HC) in benign thyroid lesions could explain the false-positive expression of galectin-3 and CD44v6 detected by reverse transcriptase-polymerase chain reaction (RT-PCR). METHODS: For galectin-3 and CD44v6, RT-PCR was performed on RNA isolated from aspirates obtained by ultrasound guided fine needle aspiration cytology (FNAC) from 123 patients with benign thyroid lesions. The results of RT-PCR analysis were evaluated against the definitive FNAC diagnosis. RESULTS: Galectin-3 expression was found in 29% follicular adenoma (FA), 26% Hashimoto thyroiditis (HT), and in 24% nodular goitre (NG). We found a statistically significant relationship between the presence of macrophages and galectin-3 positivity in NG and HT samples (P < 0.0001 and P = 0.0087 respectively). We found a statistically significant (P = 0.0219) relationship between the presence of HC and galectin-3 positivity in HT and a tendency of such a relationship (P = 0.0838) in NG. CD44v6 expression was found in 29% FA, 33% HT and in 18% NG. We found a statistically significant relationship between the presence of HC and positive expression of CD44v6 in NG (P = 0.0003) and a strong tendency of such a relationship in HT (P = 0.0571). We did not find a statistically significant relationship between the presence of macrophages and CD44v6 positivity. In FA, we did not find a statistically significant relationship between the presence of macrophages or HC and galectin-3 or CD44v6 positivity. CONCLUSION: Our results suggest that the presence of macrophages and/or HC may explain the positive expression of galectin-3 and CD44v6 detected by RT-PCR in HT and NG cytological samples.

Sclerosing epitheloid fibrosarcoma. A report of two cases.

Sclerosing epitheloid fibrosarcoma is a rare, histologically well-defined member of adult fibrosarcoma group of soft tissue tumors. Its main histological features are nests and cords of rounded tumor cells surrounded by hyalinized collagenous stroma. Epitheloid appearance with marked sclerosis and infiltrating growth pattern, along with occasional immunohistochemical positivity for epithelial markers may be highly suggestive of infiltrating carcinoma. Despite of bland cytological features clinical course is often protracted with a high local recurrence rate and late metastases. In this report, we present histopathological characteristics of two cases of sclerosing epitheloid fibrosarcoma, together with their clinical presentation, follow-up information and differential diagnosis.

RT-PCR detection of tyrosinase, gp100, MART1/Melan-A, and TRP-2 gene transcripts in peripheral blood of melanoma patients.

AIM: To detect the expression of genes encoding tyrosinase, gp100, MART-1/Melan A, and tyrosinase-related protein-2 (TRP-2) in peripheral blood of melanoma patients by reverse transcription-polymerase chain reaction (RT-PCR). METHODS: Nineteen peripheral blood samples were obtained from 17 melanoma patients. When tested, 15 of them presented with clinically detectable metastatic disease. Samples of peripheral blood (7 mL) were collected from each patient into vacutainer cell preparation tubes. Mononuclear cells were isolated, total cellular RNA extracted, and then used as a template for reverse transcription to complementary DNA (cDNA). The cDNA was thereafter assayed by PCR for the expression of melanocyte-associated transcripts of tyrosinase, gp100, MART1/Melan-A, and TRP-2 genes. RESULTS: Gp100 gene expression was detected in 13 out of 19 samples. In 4 of them, TRP-2 gene expression was also detectable. Expression of tyrosinase and Melan-A/MART-1 genes could not be observed. Interestingly, gp100 and TRP-2 gene transcripts were detected in patients having recurrent and/or metastatic disease at the time of testing. CONCLUSION: The results we obtained support the use of RT-PCR assay for indirect detection of melanoma cells in peripheral blood of melanoma patients. As the transcripts for the tyrosinase gene and MART-1/Melan A gene were not detected, additional optimization experiments of RT-PCR assay are required.